Fiber reinforced concrete

Historical perspective:  The concept of using fibers as reinforcement is not new. Fibers have been used as reinforcement since ancient times. Historically, horsehair was used in mortar and straw in mud bricks. In the early 1900s, asbestos fibers were used in concrete, and in the 1950s the concept of composite materials came into being and fiber reinforced concrete was one of the topics of interest. There was a need to find a replacement for the asbestos used in concrete and other building materials once the health risks associated with the substance were discovered. By the 1960s, steel, glass (GFRC), and synthetic fibers such as polypropylene fibers were used in concrete, and research into new fiber reinforced concretes continues today.


Effect of fibers in concrete:   Fibers are usually used in concrete to control plastic shrinkage cracking and drying shrinkage cracking. They also lower the permeability of concrete and thus reduce bleeding of water. Some types of fibers produce greater impact, abrasion and shatter resistance in concrete. Generally fibers do not increase the flexural strength of concrete, so it can not replace moment resisting or structural steel reinforcement. Some fibers reduce the strength of concrete. The amount of fibres added to a concrete mix is measured as a percentage of the total volume of the composite (concrete and fibres) termed volume fraction (Vf). Vf typically ranges from 0.1 to 3%. Aspect ratio (l/d) is calculated by dividing fibre length (l) by its diameter (d). Fibres with a non-circular cross section use an equivalent diameter for the calculation of aspect ratio. If the modulus of elasticity of the fibre is higher than the matrix (concrete or mortar binder), they help to carry the load by increasing the tensile strength of the material. Increase in the aspect ratio of the fibre usually segments the flexural strength and toughness of the matrix. However, fibres which are too long tend to "ball" in the mix and create workability problems.

Some recent research indicated that using fibers in concrete has limited effect on the impact resistance of concrete materials. This finding is very important since traditionally people think the ductility increases when concrete reinforced with fibers. The results also pointed out that the micro fibers is better in impact resistance compared with the longer fibers.

The High Speed 1 tunnel linings incorporated concrete containing 1 kg/m of polypropylene fibres, of diameter 18 & 32 m, giving the benefits noted below.

Benefits 

1. Polypropylene fibres can:
2. Improve mix cohesion, improving pumpability over long distances
3. Improve freeze-thaw resistance
4. Improve resistance to explosive spalling in case of a severe fire
5. Improve impact resistance
6. Increase resistance to plastic
7. Some developments in fiber reinforced concrete

The newly developed FRC named Engineered Cementitious Composite (ECC) is 500 times more resistant to cracking and 40 percent lighter than traditional concrete.[citation needed] ECC can sustain strain-hardening up to several percent strain, resulting in a material ductility of at least two orders of magnitude higher when compared to normal concrete or standard fiber reinforced concrete. ECC also has unique cracking behavior. When loaded to beyond the elastic range, ECC maintains crack width to below 100 m, even when deformed to several percent tensile strains.

Recent studies performed on a high-performance fiber-reinforced concrete in a bridge deck found that adding fibers provided residual strength and controlled cracking. There were fewer and narrower cracks in the FRC even though the FRC had more shrinkage than the control. Residual strength is directly proportional to the fiber content.

A new kind of natural fiber reinforced concrete (NFRC) made of cellulose fibers processed from genetically modified slash pine trees is giving good results[citation needed]. The cellulose fibers are longer and greater in diameter than other timber sources. Some studies were performed using waste carpet fibers in concrete as an environmentally friendly use of recycled carpet waste. A carpet typically consists of two layers of backing (usually fabric from polypropylene tape yarns), joined by CaCO3 filled styrene-butadiene latex rubber (SBR), and face fibers (majority being nylon 6 and nylon 66 textured yarns). Such nylon and polypropylene fibers can be used for concrete reinforcement.

What Are Magnetic Bearings?

Bearings are used to create frictionless movement between two parts. There is a wide variety of bearings including ball bearings, needle bearings, thrust bearings and even magnetic bearings. What is a magnetic bearing? Well as the name suggests it is a bearing that supports its load using magnetic forces rather than using mechanical contact. Usually in a bearing the bearing touches the two parts and the load is moved along, with a magnetic bearing they don't even have to touch, it is all done by magnetic force. This means the bearing can levitate and rotate its load without wear and friction which is impossible to avoid with non-magnetic bearings as it needs physical contact.

What uses are there for magnetic bearings?

The great thing about magnetic bearings is that there is no contact and so no friction and so no need for lubrication and they can operate in a vacuum. For these reasons magnetic bearings are used in a lot of machines with pumps and motors and generators. A common machine that you will know is your electric meter reading machine. Magnetic bearings are used within these machines to help read the power of a buildings electrical consumption. Other industrial appliances you will expect to find them are electric power generation, petroleum refining, machine tool operation and natural gas pipelines.

What are the advantages of using magnetic bearings?

The main advantage to magnetic bearings which we have already mentioned is the no-contact aspect and so no need for lubrication. But what does this really mean, why is it so advantageous? Elimination of the lubrication in certain machines means the elimination of the lubrication system as well. For example with oil lubricated bearings there is no need for the whole oil lubrication system for the pumps, valves, coolers, ducting and so and so on. Every part in a machine is at risk of failing and so removing a system or part of it with the machine still being able to work removes one of the risks, plus it saves the manufacturer money from having to build and install this section.

A lot of machines need to operate at high temperatures, now the bearing is fine to cope with these temperatures but the lubricant is often not and sets on fire or fails in other ways when it reaches a certain temperature point. By not needing a lubricant a magnetic bearing can be used in these high temperature machines with no problems. 

There are many advantages to using magnetic bearings, these are just a few but many more exist, such as better vibrational control, improved reliability of the bearing and fewer failures, longer life of the bearing as there is no wear and tear and so on.

What Is Directional Drilling And Why Is It Used?

Directional drilling is the practice of drilling non-vertical wells.  This was invented in the 1920s when it was originally used in the oil fields to increase oil production.  In the earlier 1990's the technology was adapted for utility installations. Directional bores have been installed for pipelines carrying things such as oil, natural gas, petrochemicals, water, sewerage and other products.  Besides crossing under highways, railroads, airport runways and areas with a lot of building congestion, installations have been made under rivers and waterways and protected wetlands.

There are three stages to go through when installing directional borings.  The first stage is called Pilot Hole.  A pilot hole is horizontal drilling that continues under and across an obstacle.  An electronic transmitter sends a signal to the surface which is read by the receiver.  This then transmits the information back to the drill rig operator.  The driller can then steer the bore path in any direction needed.

The second stage is called Pre-ream.  Once the pilot hole is complete, the hole must be enlarged to a suitable diameter to safely install the product lines.  This is accomplished by "pre-reaming" the hole to a larger diameter.  A reamer is pulled back and rotated while drilling fluid is pumped to cut and remove solids in the hole.  Usually, the reamer is attached to the drill string on the opposite end of the borehole and pulled back into the pilot hole.

Lastly, the third stage is called Pullback.  Once the drilled hole is enlarged, the conduit can be pulled through it.  A reamer is attached to the drill string and then connected to the product by a swivel.  The swivel allows the reamer to turn without turning the product with it.  The drilling rig then begins the pullback operation, rotating and pulling on the drill string as well as circulating the drilling fluids.

The use of directional drilling is growing rapidly and is expected to continue to grow in popularity in the future.

Diamond Bits for Drilling and Mining

If you aren't familiar with diamond drilling bits that's not surprising because they are more of a specialized drill bit. Diamond drill bits are used to drill holes into brick, stone, and concrete, and they are usually used for larger holes in these materials.

Diamond bits are usually not used on any other materials. The bit is made of a metal cylinder with a fairly soft steel mount on an arbor. At the open end of the cylinder industrial diamond are embedded.

The segments of the bits are thicker than the actual cylinder wall, so the larger portion of the bit is not rubbing in the hole that is being bored. The sloped slots will help to move the dust away.

You can use diamond bits dry or using water as lubrication. Selecting the right diamond drill bits for your application is very important to ensure you get the desired results. The material and the thickness of the material are the factors that determine what diamond bits are right. There are plenty of charts online so you should be able to quickly determine what it is you need.

In order to get the most out of your diamond tip drill bits read the manual that came with both your diamond drill bits and your drill. The bit is actually only a small part of the success of your project.

Successful diamond drilling is considered both a science and an art. It requires choosing the right diamond tip drill bit, which means you have to have an understanding of the applications.

Before you start to drill, you should visually examine the bit for any damage and never use if you see damage. If a bit is damaged or not correctly mounted it can be very dangerous. You should always have your safety footwear on, snug clothing, hearing protection, safety goggles, and the right respiratory equipment.

It may take you a bit of time to get used to using diamond core drill bits, but once you see what it can do, don't be surprised if you quickly become addicted.

You can purchase a full selection of diamond drill bits online. Here you will find quality and pricing, as well as a great deal of information on how to use your bits and get the maximum benefits from your diamond drill bits.

If you still aren't sure why you should use diamond cutter drill bits, read on. In case you didn't know it diamond is the hardest material man knows, and when you use a diamond bit it grinds away the material. Because diamond is so hard it can actually be used on all materials. Diamond can make a good alternative to carbide and other blade types. Diamonds can grind away material at the nano or micro level, where carbide drill bits cut with a sharp cutting edge.

The biggest advantage to using diamond for drilling besides the fact it will drill anything, it that there is minimal chipping, faster drilling, less noise, and less material loss.

Merits and Demerits of Black cotton soil

Merits:   The enrich agro-friendly contents make black cotton soil fertile. These soils are highly moisture-retentive, thus responding well to irrigation. These are enriched with calcium carbonate, magnesium, potash and lime which are all nutrients. Poor phosphoric contents renders rich  production of corps like cotton. The iron-rich granular structure makes them resistant to wind and water. Fertility, erosion resistance, and properties of retaining moisture in their grain are the most useful condition for better crops growth. So these soils are the best option for farmers who like to produce plenty of crops.   

Demerits:   These soil contains fine clay particles. This property  induces a great affinity to water of such type of soil. Alternate swelling and shrinkage in extensive limit during wet and dry process respectively results cracks in soil without any warning. 

These cracks may sometimes extent to severe limit like ½” wide and 12” deep. So building to be founded on this soil may suffer severe damage with the change of  atmospheric conditions.

Polystyrene (PS)

Polystyrene is an inexpensive and hard plastic. Polystyrene has a long history of evolution behind it. In 1839, a German apothecary called Eduard Simon discovered polystyrene. Eduard Simon isolated the substance from natural resin; however, he did not know what he had discovered.

Polystyrene is a strong plastic created from ethylene and benzine that can be injected, extruded, or blow molded; making it a very useful and versatile manufacturing material. However, do not forget to recycle polystyrene products. You can get more information about Polystyrene at www.worldofplastic.net

Model cars and airplanes are made from polystyrene, and it also is made in the form of foam packaging and insulation (Styrofoam is one brand of polystyrene foam). Clear plastic drinking cups are made of polystyrene. So are a lot of the molded parts on the inside of your car, like the radio knobs. Polystyrene is also used in toys, and the housings of things like hairdryers, computers, and kitchen appliances.

Polystyrene is a vinyl polymer. Structurally, it is a long hydrocarbon chain, with a phenyl group attached to every other carbon atom. Polystyrene is produced by free radical vinyl polymerization, from the monomer styrene. It is used primarily as a dielectric material in a wide range of components together with lenses, observation windows, x-ray equipment and radiation detectors.

Polystyrene is hard and brittle and has a density of 1.050 g/cm3. It is represented by the chemical formula, C8H8. Most of the polystyrene properties are as a result of the unique properties of carbon. It is highly flammable and burns with an orange yellow flame, giving off soot, as a characteristic of all aromatic hydrocarbons. Polystyrene, on oxidation, produces only carbon dioxide and water vapor.

Why Fibreglass Roofing Sheets Offer Greater Protection & Durability

As the roof is one of the most important protective components of any building, the use of Fibreglass Roofing Sheets is worth serious consideration. Fibreglass, or as it is correctly known Glass Reinforced Plastic, is one of the most durable and water resistant materials available today. Among its other qualities are a resistance to fire and a heat, electricity and sound insulator. The thermal insulation properties alone will generate considerable savings on heating and power bills. It will also give added value to any property it graces.

Fibreglass, as it is known today, was invented in 1938 to be used as a material to provide insulation. However, it was soon shown to have wider and far superior properties. The combination of glass with plastic polyester resins gives this remarkable product a stretchable and flexible strength combined with an ability to support heavy loads. It is a truly versatile substance and ideal for providing safe and secure covering for what can prove to be the most vulnerable region of a home.

Due to this strength, a roof made from Fibreglass Roofing Sheets will have a long life (predicted to be anywhere between 20 and 30 years) and be able to withstand the natural forces which readily assail roofs anywhere. Considering the other uses to which Glass Reinforced Plastic is put - hulls of boats, water tanks, aircraft fuselages and automobile bodies to name but a few - this has to be outstanding choice for the discerning customer.

Fibreglass Roofing Sheets can be used on any style of roof from pitched to flat and for any roofing purpose including extensions and porches. However, they are particularly effective when used on flat roofs or those currently covered in felt. Flat roofs, however well-established, are notoriously prone to leakage. This is because water will find any place to settle and then seek a way to run off which will inevitably be through any fault in the roof.

GRP Fibreglass Roofs are an indemnity to that. Their water resistant qualities mean that no fluid can find any possible spot where it can leak through and cause damage below due to the fact that there are no joints in the roof's construction. All this puts installation costs into perspective because a fibreglass roof is going to save the occupant of the property any amount of money in either repair or placement bills to both roof and possessions.

The construction of roofs made from Fibreglass Roofing Sheets is quick and the design and materials meet all building regulations. The required roof is moulded in the factory and then transported to the site. One special advantage is that no heat or blow torches are required to fit the roofing sheets. The sheeting is cold applied. There is, therefore, none of the tarry smell of bitumen always associated with the application of a felt roof.

The sheets themselves are decorative and attractive in appearance. They can be any colour the customer chooses. They can easily take the weight of a person walking on them, but are also non-slip. This makes cleaning an easy task. It is even possible to use a high pressure hose, which would not be advisable with roofs made from other materials, especially felt. Otherwise, these roofing sheets are totally maintenance free.

Corrugated glass fibre roofs are especially useful for buildings that require a considerable amount of internal light. The clear nature of the GPR roof allows obscured light to flow through providing a bright atmosphere within the building itself.

So there can be no doubt about the versatility and utility of this method of comprehensive roofing. It is seen as the way of the future and expected to replace most other roofing styles in the years to come. New buildings will be equipped with it as a measure of improving their value and quality and older buildings, whose integrity and appearance have suffered to do the use of current materials, will have their roofs replaced with this younger, flamboyant, but more reliable substance.

We can all be glad that Russell Games Slater experimented with fibres back in the late 1930s because, without his pioneering expertise it is possible that for tears to come roofs may have been doomed to torment those who lived under them with leaks and storm damage. Now, thanks to careful research, the system of Fibreglass Roofing Sheets has made all those worries a thing of the past. Today it is possible to feel on top of the world with a firm, reliable and safe roof overhead.  

Glass-Reinforced Plastic (Grp) And Its Usages

Glass-reinforced plastic (GRP), is a composite material or fibre reinforced plastic made of a plastic reinforced by fine fibers made of glass. Like graphite-reinforced plastic, the composite material is commonly referred to by the name of its reinforcing fibers (fiberglass), an example of part-for-whole metonymy.

First usages of GRP

GRP was originally developed in the UK during the Second World War as a replacement for the molded plywood used in aircraft radomes, its first main civilian application was for building of boats, where it gained acceptance in the 1950s, and now plays a dominant role. GRP is a versatile material with many uses.

Telecommunications industry

GRP is used in the telecommunications industry for shrouding the visual appearance of antennas, due to its RF permeability and low signal attenuation properties. It may also be used to shroud the visual appearance of other equipment where no signal permeability is required, such as equipment cabinets and steel support structures, due to the ease with which it can be molded, manufactured and painted to custom designs, to blend in with existing structures or brickwork.

Storage Tanks

Storage tanks can be made of GRP with capacities up to about 300 tonnes. The smaller tanks can be made with chopped strand mat cast over a thermoplastic inner tank which acts as a preform during construction. Much more reliable tanks are made using woven mat or filament wound fibre with the fibre orientation at right angles to the hoop stress imposed in the side wall by the contents. They tend to be used for chemical storage because the plastic liner (often polypropylene) is resistant to a wide range of strong chemicals. GRP tanks are also used for septic tanks.

House building

GRP also used in the house building market for the production of roofing laminate, door surrounds, over-door canopies, window canopies and dormers, chimneys, coping systems, heads with keystones and sills. The use of GRP for these applications provides for a much faster installation and due to the reduced weight manual handling issues are reduced. With the advent of high volume manufacturing processes it is possible to construct GRP brick effect panels which can be used in the construction of composite housing. These panels can be constructed with the appropriate insulation which reduces heat loss.

For Piping

GRP and GRE pipe systems can be used for a variety of applications, above and under the ground.

Firewater systems

Cooling water systems

Drinking water systems

Waste water systems/Sewage systems

Gas systems

Chopped Strand Mat

Chopped strand mat or CSM is a form of reinforcement used in GRP. It consists of glass-fibres laid randomly across each other and held together by a binder. It is typically processed using the hand lay-up technique, where sheets of material are placed in a mold and brushed with resin. Because the binder dissolves in resin, the material easily conforms to different shapes when wetted out. After the resin cures, the hardened product can be taken from the mold and finished. Using chopped strand mat gives a GRP with isotropic in-plane material properties.

GRP is an immensely versatile material which combines lightweight with inherent strength to provide a weather resistant finish, with a variety of surface texture and an unlimited colour range available. 

Steel Fibre for High Performance

Since ancient times something or other has been used in the basic construction material for extra strength. Like earlier, when houses were made from mud, mud was mixed with some ratio of straws for more strength. Today the same technique of mixing two different elements for strengthening construction material is used. Concrete nowadays is the fundamental construction material and to make it more strong, steel fibre and mica are used in it. This increases the structural ability of the concrete. So wherever additional tensile strength and durability is required,  steel fibre reinforced concrete, SFRC is used.

Steel fibres are the small and circular steel wires  having length between 30mm to 100 mm. It comes in three varieties viz: straight steel fibre, indention steel fibre and hooked ends steel fibre.  Further concrete is made strong with hydrate-cement,  0.25 - 2 volume % of steel fiber and fine-aggregate. For better result these fibres are dispersed randomly in concrete.

Also by adding steel fibre to concrete, its durability, flexural and tensile strength increases. But other mechanical properties of the concrete vary with the volume, shape, percentage, size and distribution of fibre. Such as fibres in a plain, round or straight shape do not develop strong bond and thus the flexural strength remains quiet low. Improved strength, toughness, post-cracking load resistance of plain cement concrete is greatly improved by adding steel fibre. This increased ability has also been proved by extensive research work on this.

Today almost all the buildings and constructions made use of SFRC and because of the huge development of airport, roads, dams, earthquake-resistant buildings in the last two decads this material has gained further popularity.

Steel fibre reinforced concrete (SFRC) is used in places where very heavy wear and tear is expected. And generally these are:

• Steel fibres are used in mining and embankment stabilization. Also it is used for making dam and water course lining.
• This is also used in the making of erosion control structures.
• Factory and warehouse floors, roundabouts, residential developments and spillways are made of steel fibre reinforced concrete.
• Tunnel segment liners, sound barriers, pontoons are also made from this kind of steel fibre and concrete.

Steel fibre tenders expect the specification and nomenclature of the material used to make steel fiber reinforced concrete. Like shotcrete is a highly fluid type concrete that is used as a spray on vertical and irregular surfaces. Before spraying and for extra strength steel mesh is installed.  Further to improve the cohesion of shotcrete during spraying, steel fibres are used in it. In these tenders you will have to specify the details in detail.

Apart from this precast elements that are manufactured at places other than the construction site and transported to these sites contain steel fibres for extra performance. These are used in almost all kinds of bridges, building and roads pavements.

Most of the industrial ground slabs are made from this material that includes airport runways etc. Cracking is highly reduced in these structures and these get additional durability with SFRC.

At present huge construction of buildings, roads and bridges is happening in Pondicherry thus Pondicherry tenders for construction and building material are in boom. This gives new business opportunities to may new as well as existing businesses. Along with this there are steel fibre tenders in the construction souk. In such tenders, repair and fencing of roads, reconstruction of buildings along with new construction is included.

Fiberglass Tubing Applications in Oil Industry

Fiberglass may be synonymous to home insulation. The glass substance that can be found in fiberglass is the same as the glass substance applied in windows and other glassware applications in houses and buildings alike. However, few may be aware that fiberglass is also used by many other industries like engineering. Primary use of fiberglass tubing can often be seen on injection wells used as reservoir pressure in oil companies across the world. Different uses of this composite in the industry vary from several applications in injection wells such as recycling wells and gas lift wells to producing wells.

Fiberglass is made up of very thin fibers of glass woven together to have its own form. It may be used mainly as reinforcement. The material, when woven across its axis is stiff and has an unbelievable strength in terms of compression and tension. It is also very flexible such that when several layers of fibers are placed on top of each other, no matter what direction they are woven, the stiffness and strength properties are basically controlled efficiently.

There are several reasons for using fiberglass tubing in the oil industry. First and foremost, the industry is looking for ways to be more cost-efficient in many aspects. One advantage of using the material is that the period of operation for the transportation of corrosive liquids like oil and/or water is prolonged up to 25 years. Another advantage is that the material is corrosion-resistant. The piping material required should be inert to different compounds like hydrogen sulfide, oxygen-containing compound, alkalis and acids. Thus, the pipes with fiberglass tubing are not subject to any deposits of paraffin or any solid precipitations. It is also proven that fiberglass weighs 5 times less than other metals but the strength displayed is practically the same, if not stronger. Amazingly, the material has a smooth inner surface, providing the entire pipe with minimum hydraulic resistance.

Applications of fiberglass tubing in pipes used for oil industry will definitely increase the possibility of having accident-free operations of oil and gas pipelines, thus reducing accident risk as well. It also helps in elimination of the depositions of salt, paraffin and other acids. As mentioned earlier, the material is corrosion-resistant, so there is no need to purchase exuberant corrosion inhibitors. Lastly, since the strength is already trusted and tried, the cost of maintenance will be significantly reduced as well.

Hammer Drill vs. Traditional Rotary Drill

Using a hammer drill, you can drill holes or insert fasteners in surfaces that are extremely hard or dense. On the other hand, conventional rotary drill cannot stand the toughness of hard surfaces and would break if used on such surfaces. The force produced by hammer drills are higher level forces, and would break the object as required to drill the hole. The masonry materials involved when using these tools include brick, concrete and stone.

Outstanding Features of a Hammer Drill

The most outstanding difference between the hammer drills and the traditional drill is that the former features a movable chuck (a drill's part that functions to hold the bit in place). Unlike the chuck of a regular drill, the chuck of this special drill can move backward and forward over a small distance; this in turn aids in the hammering of the wall while the drills spin. Regardless of its short range movement, the movement of the chuck of this special drill is quite rapid, the outcome is hammering into the wall thousand or hundred times per minute! The masonry or stone is easily broken down with the aid of the hammering motion, paving way for successful and smooth entry of the drill bit. The unit measurement of the power/strength of a hammer drill is IPM – Impacts Per Minute – this stands for the frequency of the chuck hammering into the wall per minute.

If you cannot afford a brand new hammer drill, you can resort to used hammer drill which also has the same capacity and produces the same result as the brand new one. This special drill is mostly employed in applications where it is necessary that the workmen combine the drill with the conventional drill for a higher benefit. The tool normally comes with a switch which is capable of turning off the hammering motion as occasion demands – in essence, the chuck would continue to stay stationary for use where conventional drilling application is required.

The new Bosch Hammer Drill features the most excellent Power-to-Weight Ratio. If you want something easy on the arms and hands, the lightweight 4.2-pound hammer drill from Bosch is perfect. Then, the most excellent power-to-weight performer is the Bosch 1191VSRK – (in its class). Bosch Hammer Drills are superb hammer drills to have in the toolbox.

For those workers who are about to execute jobs that they are not certain of the nature of the surfaces they would encounter, the hammer drill is a wiser option to go with. As a mason, you may not know if the job requires drilling into stone and wood objects; therefore it is wise to choose the tool that can tackle whatever situation you meet.

The special drill may come with electrical power cords. At other times, it comes with a more flexible battery-operated feature.

If you are on budget, you can choose from the used hammer drills; however ensure that you are buying from a reliable source to be sure of the tool's effectiveness.

Micropile 101

Cracks and settlement are facts of life when it comes to construction using concrete foundations. There have been many methods of repairing structures once they have settled, including helical piles, push piers and Micropiles. Each has it’s own uniqueness and applications where they should or should not be used. Helical piles are a simple and cost effective solutions to light weight structural repairs. Push piers are great for lifting heavy structures in a cost effective manner. Now, Micropiles are growing in popularity for reducing the effects of settlement in new and existing structures.

There are many names for Micropiles – minipiles, pin piles and root piles being the most common. These piles are rotary drilled and grout reinforced small diameter piles which can be installed to depths of 200 feet and through very dense layers of soil and rock. Unlike helical piles or push piers, Micropiles are unaffected by cobbles and trash in the soil. Their sacrificial bit is designed to drill through these tough soils and embed themselves in load bearing rock layers, while maintaining a grout column around a structural steel member in the center of the column.

Like helical piles and push piers, Micropiles can be installed in limited access areas with relatively small equipment. This maneuverability makes them ideally suited for foundation repair applications. Portable equipment has been developed to allow for access to basements and other low overhead applications where soils or access is limiting to other more conventional methods of foundation repair.

The process of installing Micropiles begins with drilling into bedrock using a specialized drilling rig. Soil cuttings are expelled with air, water or grout followed by grouting the column that has been created by the sacrificial carbide bit and threaded rod. The Micropile tops are cut to elevation and a sleeve is inserted to adapt to the underpinning bracket system. Load testing can be easily performed on production piles or test piles near the proposed locations.

Micropiles and their inherent advantages have grown in popularity and acceptance by contractors and engineers alike over the past several years. With the advancements in drilling equipment and underpinning brackets, Micropiles are sure to become more popular in the foundation repair industry.

Bamboo

One of the most enduring images of India’s freedom struggle is that of Mahatma Gandhi setting out on the Salt March in 1930, on a 140 kilometre trek from Ahmedabad to Dandi. All he had by the way of support were the multitudes behind him, and the bamboo stave by his side. The bamboo in his hands, today more than ever before, is one of the newest hopes for a sustainable future. Found in almost every kind of climate and region, from cold mountains to tropical forests and marsh lands, the bamboo is the fastest growing plant on our planet. Environmentalists believe that if bamboo were used in a major way in afforestation programs the world over, there would be a significant reduction in global warming. Here are some of its other benefits to humans and their environments --

• It is one of the cheapest renewable sources of building material available to man.
• At the same time, it provides rural communities with a sustainable livelihood.
• It is one of the fastest growing components of forests, and thus plays an important role in the development of animal habitats.
• It costs neither a lot of energy nor money, to cultivate.
• Bamboo has been an important part of art, music, tradition and ceremonies through out the Asian continent.

Varieties
There are approximately 91 general and about 1000 species of bamboo around the globe. These vary in height from about one foot plants to giant bamboos that grow over 100 feet. Broadly speaking, Bamboo is divided into 2 main classifications – Running Bamboo and Clumping Bamboo.

1. Running Bamboo – This type of Bamboo travels under the soil using creeping rhizomes and emerges out of the ground at a distance from the original source. This variety is normally found in temperate climate countries like China and Japan. It is very effective in binding the soil together as the rhizome intersection is extensive and strong. Each joint of the Running bamboo stem has a single bud, which in many cases grow to become a new bamboo clump.
2. Clumping Bamboo – In this variety, the clump and the rhizome are a single entity, in which the upper portion of the rhizome has buds. The bud then grow into a new rhizome which turns upwards and emerges, from the ground, as a second clump close to the original. This variety can also be grown from cuttings. They are normally found more in tropical and semi tropical climates.

Growing Bamboos
Bamboos need plenty of water in a well drained, fertile soil to grow optimally. This is why they are most commonly found on river banks or the edges of swamps, never directly touching the water. During the dry season, bamboo clumps lie dormant, spreading through shoots sprouting from their base once it rains. The bamboo is an extremely sturdy plant and is naturally quite resistant to pests though the occasional Running Bamboo plant is prone to the Bamboo Mites which make a small but distinctive web on the plant. Some bamboo varieties may also be grown indoors.

Precautions During Bamboo Cultivation

• Large bamboo produces large woody underground rhizomes that could damage paving, buildings or drainage systems if planted too close to these or other structures.
• The roots which grow from the rhizomes of clumping bamboo are long and fibrous like those of palms or large clumping grasses. These are useful in stabilising the soil and preventing erosion, but may also create problems. Being flexible and fibrous rather than hard and woody, these roots will grow into and along slotted drainage pipes or any cracks in metal or ceramic pipes.
• Bamboo rhizomes grow underground to emerge quite a distance away from the mother plant. So if planted in a wet, well drained and rich soil, bamboo can quickly spread and strangle other trees and plants in the area.
• Once established as a grove, it is difficult to completely remove bamboo without digging up the entire network of underground rhizomes. If bamboo must be removed, an alternative to digging it up is to cut down the culms, and then repeatedly mow down new shoots as they arise, until the root system exhausts its energy supply and dies. If any leaves are allowed to photosynthesize the bamboo survives and will keep spreading.

Traditional Uses
The bamboo is a highly useful plant, a renewable resource with multiple uses. It has played a crucial role in the life of people all across south and south east Asia. Here are some of them --

• Bamboo pulp is used for making paper
• It may be burnt as fuel
• Bamboo is known not only for the aesthetic beauty it imparts to its surroundings, but also for its tensile strength. Research has shown that during structural engineering tests, bamboo has a much higher tensile strength than many alloys of steel and a higher compressive strength than many mixtures of concrete. Which is why, for long, it has been a standard material in construction.
• Its leaves are a good fodder for animals and fish.
• Bamboo is used to make simple bowls, glasses etc by the simple expedient of cutting it from above and below a node.
• It is used to make musical instruments. The flutes of Benares are a good example of this.
• Many canes of bamboo lashed together, are still used as rafts and boats across the world.
• In 1854, Henricg Globel, a German watchmaker made the first true light bulb. He used a carbonised bamboo filament inside a glass bulb. In 1879, Thomas Alva Edison too used bamboo splits as filaments, working with bamboo obtained from Japan. The bamboo filament tended to last about forty hours before burning out.
• Bamboo is an important ingredient in many world cuisines. Its shoots are considered a delicacy in many parts of the world and are consumed in a variety of ways. They are sometimes pickled and used as a condiment, or used with other vegetables in a stir fry. Bamboo sap is also used to make a sweet wine while its leaves are used as wrappers for steaming food. The inner hollow in the bamboo stalks are also used to cook rice and boil soup. Bamboo along with other ingredients is used for making pancakes as well.
• Bamboo plays an important role in the Chinese medicine system as well as in Ayurveda. Its roots are used to treat kidney problems and bamboo secretions are considered helpful in alleviating symptoms of asthma. Its sap is said to reduce fever and roots and leaves have properties that have been used to treat cancer. The Chinese also use bamboo to treat many infections. Bamboo skin prevents bacterial growth due to its antioxidant properties.

Modern Uses of Bamboo
Though one has stepped into the modern world today with changing lifestyles and choices, bamboo is still used in the same way across large parts of the world as it was used in the past. In fact it is rightly believed by many that no other plant has had the impact that bamboo has had on so many cultures over such an extended period of time. But now, with the help of technology, scores of new uses have been found for the age old bamboo. Here are some --

• Bamboo furniture
• Bamboo flooring
• Bamboo blinds
• Bamboo is a very comfortable eco fibre which is naturally anti-microbial. Due to the presence of micro pores, the fabric absorb three times more moisture than cotton, making it very comfortable to wear in the hot summer.

Did You Know?

• Bamboo can grow about 4 feet in under 24 hours.
• A Bamboo plant can be continuously re-harvested every 3 years, without causing any negative impact on the soil and the environment.
• The dense roots of the bamboo plant are so deep into the soil and remain firmly intact that they prevent soil erosion in a very effective manner.
• It retains twice as much water in the underground watershed.
• It consumes nitrogen and thus remove pollution.
Bamboo plant produces 35% more oxygen than any other tree species. Bamboo also protects against ultraviolet rays.
• Soft bamboo shoots, stems, and leaves are the major food source of the endangered Giant Panda of China.
• The plant marketed as "lucky bamboo" is actually an entirely unrelated species, Dracaena sanderiana.
• Bamboo is the only living thing that survived the Hiroshima atomic blast. It also provided the initial re- greening of that place.

Lucky Bamboo

Lucky Bamboo is, strangely enough, not a bamboo at all. It is a resilient member of the lily family that grows in the dark, tropical rainforests of Southeast Asia and Africa. Lucky Bamboo has long been associated with the Eastern practice of Feng Shui - or the bringing of natural elements of water, fire, earth, wood and metal into balance within the environment. It is believed to be an ideal example of the thriving wood and water element, with the addition of a red ribbon sometimes tied around the stalks - which is believed to "fire" the positive flow of energy or chi in the room.

Mud Pumping During Foundation Repair

Mud Pumping is the process of filling voids under concrete slab foundations, patios, pool decks, and driveways. There are several similar terms used to describe similar processes. Mud Pumping, mudjacking, slab jacking, concrete pumping, and pressure grouting all refer to similar but different processes.

Mudjacking and slab jacking are essentially the same process of pumping concrete or a concrete/mud mixture into voids underneath a concrete slab in an effort to raise the slab. Usually this works with smaller slabs such as driveways and patios. It is far more difficult and complex to raise a concrete slab foundation and the entire attached commercial building or home with this method. Concrete pumping is a similar process but it may use a high or low strength concrete. Mud pumping and pressure grouting refer to a process of simply filling voids underneath a concrete slab foundation without trying to raise the foundation or structure. This will give the foundation the support it needs between itself and the ground. Usually the commercial or home foundation will have been raised, stabilized and leveled by a repair contractor prior to the mud pumping or pressure grouting.

When there has been an imbalance in the moisture in expansive soils then the concrete slab foundations that rest on top of the soil will experience movement. The movement can be lateral, upward or downward. One example could be a group of shrubs or large trees on one side of a home that is absorbing large amounts of water around and under a portion of the foundation. The expansive soil in this area will shrink relative to the soil in other areas under the foundation because it will have a lower water content. When the soil shrinks too much it will lose contact with the foundation and the foundation has lost its support in that area. If the area is too large then the weight of the building structure and foundation will cause the foundation to crack and "fall." That series of events will cause structural damage to the commercial building or home and may necessitate the need for home foundation repair or commercial foundation repair.

Many times after the leveling process has been completed for a home foundation or commercial building foundation there will exist voids under the foundation. A concrete on slab foundation was never designed to be a "bridge" and support weight between two support points. This type of foundation was designed to rest on the soil underneath and the soil provides the ultimate support for the foundation and the attached building or home. Therefore the repair contractor should fill these larger voids so that the concrete slab foundation can "rest" on the ground.

Regardless of the reason for the void under the home foundation, mud pumping should be used to fill any large voids with a low strength cement or a slurry of mud and cement. If interior bell bottom piers were installed then they provide easy access to the area of the void. Sometimes one inch holes will be drilled through the slab to allow access to the area of the void. Then the slurry will be pumped under pressure into the voids. At this time all of the water faucets in the home or the commercial building should be turned on to keep a stream of water flowing through the sewer lines. Toilets should be flushed periodically and the washing machine should wash some clothes. This will prevent the slurry from clogging any sewer line that may have a crack or break prior to or during the leveling process.

After the mud pumping process has been completed and the slurry has hardened the work crew will pack the remaining openings in the interior portion of the foundation with a select fill dirt. The openings will then be covered with a layer of plastic sheeting to help prevent moisture from seeping into that area. The area will then be patched with new concrete. The patched area will be smoothed and allowed to dry for a number of days. Outside piers will be packed with sand and/or topsoil. The commercial or home foundation repair job is now complete and the property owner can feel comfortable that this solution will last the life of the property structure.

white cement and its characteristics....

White cement has become the part and parcel of each house.It has become an essence and necessity for an outstanding look.White concrete in all three aspects of economic, social, and environmental has shown an outstanding sustainable development resulting in greatest popularity with an increasing graph.It increases the durability,reduces the permeability and enhances the overall durability of the concrete. This, in turn, enhances the lifespan. White cement has its unique properties and uses. White cement is produced from raw materials low in coloring elements such as iron, manganese and chromium, normally utilizing high grade limestone, white clay and pure silica as raw materials .Now in this modern world it has a wide spread of uses.Mostly it is used in terrazzo,glass fibre reinforced concrete,as a concrete countertops,roof tiles,cold weather construction,sound walls swimming pools and spas ,etc.It has created wonders in aesthetic purposes. Greater reflectivity will increase visibility,hence it reduces the level of artificial lightning ,enhancing road safety,increase popularity of monumental beauty,dams and bridges. larger surface area and fineness adds to its superiority by making its use in repair works and tile formation and floors It reflects the heat and prevents the seepage ,used to produce Highly adhesive dry-mixes with low shrinkage and no efflorescence.contribute to a better environment by reducing the "Heat Island" effect* economic characteristic makes it unique by Reducing long-term maintenance costs.It doesnt easily fade,eliminates the need for vibration for settling, reduces air pollution,used to make prefabricated pavers and tiles ,adhesive,paints and dry mixes.the unique properties and wide variety uses has created a greater demand of it and price.though its price is very high but overall comparatively it is economic and sufficient in cost saving in future.Its classic features and capability not only has surprised the people but has resulted in greater productionRecent data reveals that India is lagging in the rapid supply and profit market.

ADITYA BIRLA group is one of the major manufacturers having base in rajasthan.through Correct initiatives production as well as demand can be increased to 15 to 25%.Demand for white cement is linked to the economic activity in any country. Broadly, it can be categorized into demand for housing construction and infrastructure creation and government projects. The real driver of cement demand is creation of infrastructure, hence cement demand in emerging economies is much higher.

The production of White Cement requires exact standards and  temperatures around 1500+ degrees.Hence,the manufacture costs much.India is lagging behind the consumption due to several reasons,less buying because of cost, labours/mason/contractors  are to command on the material of supply and hence mostly they prefer to use grey cement because of lack of awareness or mentality of gaining money,white cement is very expensive compared to foreign countries and  competition factor.Effective methods like use of bulk bags,increase production to decrease the overall price,spreading awareness,encouraging more export through the ship , encouraging usage in infrastructures and government projects and etc ,will help to reach the milestone, maintaining contacts with tile,aesthetic related companies for more diversification and etc.

Discover The Essential Role Of Tubular Piling In Construction

Tubular piling might well sound like a particularly painful and unique medical condition to the layperson however it is actually an extremely important part of large-scale construction. Piling is traditionally made of wood and it refers to long structural beams in various shapes that are driven deep into the ground using piling rigs in order to support the structure of the building project.

Now piling comes in various forms such as concrete and steel with different shapes dependent on the technical specifications of the building project. Many factors affect the use of piling such as the load of the structure, the depth of the foundation, the ground density and the soil type. The piling can be driven into the ground or drilled in, however the advantageous benefits of driving piling is that the soil around the piling becomes compact.

Piling is used in deep foundations and the shape of piling depends on the structure being built, for large scale construction tubular metal piling is driven into the ground then filled with pre-stressed concrete. The number of tubular piles depends on the individual structure of the project and the weight that the deep foundations need to incur. H-beams or square concrete piles are used for certain projects such as domestic residences or small scale apartments.

A case study in 1960 was performed in Vietnam when building a major road from the city of Saigon North. The soil below the surface consisted of layers of muck on top of clay and sand which meant that there was no solid foundation to build on, risking subsidence under the massive weight of traffic. Massive metal tubular pilings were driven into the ground then filled with concrete. Test were carried out on them to evaluate their load capacity.

It is recommended that when dealing with piles over a certain size that tests are carried out on their load capacity and how they perform under certain weights. The production of tubular piles must be done to various standards regulated by industrial watchdogs. The process is called rolling and welding tubing where exactly circular tubes are formed by rolling sheets of metal and then welding them together.

Other forms of piling are drilled piles, underreamed piles and auger cast piles. They serve different purposes such as high load bearing or specialist systems for unstable subsurface sediment. They are essential to large-scale construction and there are a few specialist manufacturers who can provide rolled and welded tubing to exact specifications.

Under reamed pile foundation for Black cotton soil

Black cotton soil contains fine clay particles. This property  induces a great affinity to water of such type of soil. Alternate swelling and shrinkage in extensive limit during wet and dry process respectively results cracks in soil without any warning. These cracks may sometimes extent to severe limit like ½” wide and 12” deep. So building to be founded on this soil may suffer severe damage with the change of  atmospheric conditions.

Under reamed piles are the most safe and economical foundation in Black cotton soil. Under reamed piles are bored cast in situ  concrete piles having bulb shaped enlargement near base. A Pile having one bulb is called single under reamed pile.

The bearing capacity of the pile is increased by increasing the number of bulbs at the base. Such type of foundations is ideally suitable in the areas where the black cotton soil or expansive soil is beyond 2.50 meter. The basic principle of under reamed pile is to anchor the structure at a depth where ground movement are negligible due to moisture variation or other reasons.

Simple tools are required for construction of under-reamed  piles like spiral auger, under reaming tool, and boring guide. This is a well proven and  established technology for construction of foundation in expansive soils. For speeding up the construction bore and under ream for large diameter and deeper pile a  mechanical rig can be used. The construction and design of such foundation can be done in accordance with Indian Standard Code of Practice IS 2911-Part III.

Types Of Drill Bits

Drill bits are tools used in making cylindrical holes. Various types of drill bits are designed for different uses.

Drill bits are equipments or tools that are used in making cylindrical holes. Drill bits can also be referred to as a drilling machine. Drill bits are available in various drill types such as metal drills, gun drills, screw machine drills, core drills, step drills, spade drills, forstner drills, masonry drills, dental or surgical drills, wood bits, twist drills, drill blank taper drills and much more.

They are designed to cut while doing a clockwise rotating motion. Several drill bits are coolant fed. They contain a channel or hole for directing the coolant fed near to the cutting edges. The split point drill heads of drill bits are used for chip clearance and for excellent centering. Drill bits can also be used in cutting aluminum, general-purpose metals, brass, copper, bronze, ceramic, and plastic, stainless steel, steel, wood, titanium and hardened materials. Various types of drill bits are designed for different uses.

Listed below are some types of Drill Bits.

Twist Drill: It drills holes in plastic, metal and wood. This drill is currently produced with a width covering a range from 0.05 millimeters to 100 millimeters while its length is around 1000 millimeters. The most usual twist drill has a tip angle of 118 degrees. This is a proper angle for an extensive array of job. It also has a long series drill for extended length twist drills. It is not advisable to drill deep holes using this twist drill.

Diamond Drill Bit: This particular drill is used in the bathroom for updating or remodeling. It is also used in redesigning your kitchen decoration. Furthermore, it is used on ceramic, glass, tile, limestone, stained glass, marble, fiberglass, porcelain, stone, slate and porcelain tile. When using this drill, the main concern is to obtain water at the edge of the drill bit. Drilling fiberglass may be done with or without water but make sure that the fiberglass has ample amount of water just to get the drill wet.

Indexable Drill Bit: This provides an excellent performance in making short-hole drillings. Stainless steel is drilled 3x in diameter and only a short-hole must be done.

Listed below are some other types of drill bits

• Adjustable Bit: This is built with a changeable cutter blade to bore holes of various sizes. It is also used for drilling gaps for wiring or piping.

• Around-the-corner bit: It is used to cut arched holes that are stretched in corners with a diagonal cutting surface.

• Auger Bits: This drill creates drill holes in wooden materials. The drill ends have a screw head so that the bits may be self fed.

• Brad-point drill: This drill looks almost the same as the usual bits but it has sharpened point to make wood drilling a lot easier. This drill has cleaner holes other than spade bits.

• Counterbore: The drill allows a screw to be driven under the wood outside. The holes that are drilled may be filled with a plug or wire.

• Drill Saw Bit: It is used to cut holes such as wood and metal and can enlarge current holes.

• Countersink: A drill that has an angled tip design that forms a "slump" in the screw head.

• Fly cutter: This one is often used to cut circles in wood and other soft metals. The diameter of circles may be adjusted by changing the cutter blade setting.

• Hole saw: It cut holes from one to six centimeters in diameter and has a center bit for directing the cutting blade edge of the saw.

• Reamer bit: The tapered bit of reamer may be used on existing holes rather than to enlarge holes.

• Screw pilot bit: This beautiful bit is used for drilling body holes. A pilot hole is used along with the countersink.

• Wire Brushes: It use to remove rust and to clean up metal and is available either as a wheel or a cup with wire brush.

• Plastic bit: This is designed with a tip so as to prevent splintering when drilling plastic. It is important to reduce the speed and slowly drill the other side of the plastic.

• Plug cutter: Use this to remove cylindrical shapes from the wood. It covers the screw using a small cylindrical plug.

Liquefaction Mitigation by Deep Soil Mixing Method (DSM)

Deep soil mixing (DSM) is an effective and versatile method of preventing damage caused by soil liquefaction. Liquefaction is the weakening and subsequent instability of soils caused by applications of force such as seismic activity, erosion, construction, or excessive load bearing. Significant movement shifts the underlying soils, allowing groundwater to rise and fill the spaces created by the movement. This release of water weakens the composition of otherwise stable soil. Soil can also become saturated and unstable through industrial dumping or by leakage from faulty retaining structures.

Too Much Moisture Creates Big Problems

When the soil contains too much water, it can fail to provide support for building foundations, causing them to shift, crack or even collapse. It can also render some geographical areas unsuitable for building by creating soil that is too wet and soft to allow safe construction. Not only is the soil too unstable to support the significant weight of new building construction, it can render existing buildings unsafe. Failure to contain liquid soils can result in seepage of toxic or noxious substances (chemicals, sewage or other waste products).

Deep Soil Mixing Can Solve Liquefaction Issues

An effective way to conduct Soil liquefaction mitigation is through seep soil mixing (DSM). The DSM method involves boring through the soil with a specialized, large-diameter auger (between three and 12 feet) equipped with mixing paddles. Once the auger reaches the appropriate depth, it is filled with cement that is released through holes on the core of the auger. As the cement fills the hole, the mixing paddles combine it with the surrounding soil to create a solidified, underground column.

In addition to its uses in building construction, DSM is also utilized in projects that require sludge stabilization such as Brownfield redevelopment and industrial cleanup. In these cases, DSM technicians can use soil reagents such as fly ash or harder, less porous soil types to reduce the moisture level of the sludge.

DSM can also be used for chemical remediation. By solidifying contaminated soil with either cement or other binders, the contaminants in the soil are isolated and solidified, preventing them from seeping into nearby water supplies. New developments include the use of zero-valent iron, carbon and special clays to create solid soils and reduce the impact of liquefaction. Traditional cement columns and solidifying agents are both effective methods of barrier construction to protect environmentally sensitive areas from infiltration, or to stabilize areas prone to soil erosion

Foundation Repair - Your Underpinning Options

When it comes to foundation repairs and your home, there are several choices that need to be made. These choices range from using helical piers or steel push piers, waterproofing or underpinning, concrete segmented piles or steel push piers or even eccentric vs. concentric piers. You will hear proponents for each different type of foundation repair underpinning system, you will also hear many different reasons why some steel push piers are better than other steel push piers. Wading through all of this information is the key to finding the right method and means of repairing your home. Here we will focus on the differences in piering systems, specifically eccentric piers verses concentric piers. First we must define the terms eccentric and concentric. An eccentric piering systems is one who’s pile axis is not in line with its applied load. A concentric pier is a pier bracket and pile who’s axis is in line with the applied load. 

Next, you must categorize these piering systems.

                      Eccentric Piers                             Concentric Piers        

                      Steel Push Piers                             Steel Push Piers       

                      Helical Piers                            Segmented Concrete Piers       

                      Micro Piers                                      Hybrid Piers

For foundation repair applications, helical piers are always eccentric in nature. The helical sections are installed through the bracketing system from the side of the pier. Micropiers are also installed through the bracketing systems from the side of the pier. The major reason for this is the relatively large equipment used to install these types of systems cannot fit below the wall or footing. 

Segmented Concrete Piles are installed directly below the footing and then a bracket or platform is installed on top of the pile to transfer the applied load to the pier. Hybrid piers are the latest concept in underpinning products. These pier systems generally use concrete filled steel pier sections installed directly below the footing and then either a steel bracket or concrete block is placed on top to transfer the load to the pier. These hybrid piers are marketed as the best of both worlds, in reality they are compromise of both worlds. They do not provide the full benefits of steel piers and they have the same negatives as the segmented concrete piles. 

As noted above, steel push piers can be eccentric or concentric in nature. Each manufacturer generally determines which design best fits their manufacturing and design capabilities and sticks with that style. Only Earth Contact Products has successfully designed and engineered both types of systems for residential use. 

What is better, eccentric or concentric? Well that is the $64,000 question. There is no real answer, because both, if designed properly and applied properly, will work well. While an eccentric designed pier requires more engineering and tighter quality control, not only can they work well but some have worked well for over 30 years. This is not to say all eccentric piers have good engineering behind them. Many are manufactured around cost constraints opposed to good engineering. Concentric steel piers are a lower tech solution that has many application advantages over its rival, the eccentric pier. They can be installed with less footing modification, they can be installed in lower headroom areas and they require less installation equipment to use. 

Concentric piers are great for crawl spaces due to the fact that a tall drive stand is not needed to drive the pier sections. For eccentric piers to be used in a crawl space you will need either a fairly deep crawl space or you will have to cut through the flooring to make room for the drive stand. Concentric piers are also not affected by deep brick ledges or other obstacles like their competition. 

The down side to most concentric piers is in their lifting or stabilization of structures. Most concentric piers do not allow room for anything more than a bottle jack (car jack) for lifting. They are pressured up with the bottle jack and then simple shims are placed between the bracketing system and the footing, the footing is then lowered onto the pier system. Bottle jacks are very undesirable for a couple of reasons. First, the structure is over lifted to allow for the steel shims (similar to segmented concrete piles). Next, with bottle jacks, the installer has no way to measure or control the hydraulic pressure applied to the structure. Most engineers frown on the use of bottle jacks for structural repairs. 

There is only one concentric pier available, that uses a hydraulic manifold lifting system and is continuously adjustable, on the market today. The Earth Contact Products Model 200 uses a hydraulic manifold system, the same system used on their eccentric push piers. This system was designed by engineers for engineers to allow for critical infinite adjustability and control in lifting structures. The Model 200 also uses a patented adjusting platform that does not require over lifting or shims. This unique combination has created large demand and acceptance of this particular concentric piering system. 

As you can see there are many variables and styles of underpinning pier systems available. So how do you choose the one that is right for your home? This is the easy part. First, hire an engineer and let him help determine your foundation repair needs. Then take your new found knowledge out into the market and wade through the variety of foundation repair contractors and find one that installs a quality piering system that has been designed and engineered to perform on your home. No bottle jacks, no shims, no shallow installation methods, just good engineering and manufacturing by a quality foundation repair company. Now, whether you are in Dallas, Texas, Kansas City, Kansas or Columbus, Ohio get out there and get your home fixed correctly and permanently. 

Slurry Walls and Soil Mixing give Construction Solid Ground

Slurry Wall Construction and Deep Soil Mixing are Important Parts of Construction

Many don’t realize it, but construction is a complicated process. People think construction projects take too long because people are not working hard. This couldn’t be further from the truth. One of the reasons certain construction projects take so long is because of the ground improvement which needs to take place. It isn’t a good idea to try to build something on ground which isn’t properly prepared to bear the weight of a structure. One key process is making sure that groundwater is kept out of the area to keep the ground from becoming saturated and shifting.

Bentonite Slurry Walls Help Establish a Barrier against Groundwater

One way to do this is with slurry wall construction. Slurry walls are usually a combination of bentonite and water inside a trough. Bentonite is an absorbent clay which increases the viscosity of the solution, so the slurry is thicker than water. The slurry exerts an outward force which counteracts the force on the outside of the trench. The slurry wall can hold as a temporary barrier until it isn’t needed anymore, or it can be replaced with concrete. Regardless of the use, the slurry is collected and recycled when it isn’t needed. This means that there is very little waste involved in this process.

Dropping Anchors with Deep Soil Mixing

Another procedure used to establish solid foundations during construction is soil mixing. There are several varieties of soil mixing, including deep soil mixing, shallow soil mixing, and backhoe stabilization. All procedures use similar processes though. A large auger (one to four yards across) is drilled into the ground while fluid grout is pumped through the center of the auger. After reaching the proper depth the auger is removed and the solution dries. This creates a solid, stable anchor pillar in the ground. These anchors are used as elements to the building contraction, or a solid point to position heavy machinery on top of.

The Critical first step of Construction

These two processes are extremely important and common in construction projects. They both require state of the art machinery and qualified technicians to be completed properly. So the next time there is a construction site which seems to be stuck in the preliminary stages, consider all the preparation work which has to be done before the plans can get “off the ground”.

Water Jet Cutter

 In the 1950s, forestry engineer Norman Franz experimented with an early form of water jet cutter to cut lumber. However, the technology did not advance notably until the 1970s when Mohamed Hashish created a technique to add abrasives to the water jet cutter. Today the water jet is unparalleled in many aspects of cutting and has changed the way many products are manufactured. Many types of water jets exist today, including plain water jets, abrasive water jets, percussive water jets, cavitation jets and hybrid jets.

Operation

The cutter is commonly connected to a high-pressure water pump where the water is then ejected from the nozzle, cutting through the material by spraying it with the jet of high-speed water. Additives in the form of suspended grit or other abrasives, such as garnet and aluminum oxide, can assist in this process.

Benefits

An important benefit of the water jet cutter is the ability to cut material without interfering with the material's inherent structure as there is no "heat-affected zone" or HAZ. Minimizing the effects of heat allows metals to be cut without harming or changing intrinsic properties.

Water jet cutters are also capable of producing rather intricate cuts in material. The kerf, or width, of the cut can be changed by changing parts in the nozzle, as well as the type and size of abrasive. Typical abrasive cuts are made with a kerf in the range of 0.04" to 0.05" (1.016 to 1.27 mm), but can be as narrow as 0.02" (0.508 mm). Non-abrasive cuts are normally 0.007" to 0.013" (0.178 to 0.33 mm), but can be as small as 0.003" (0.076 mm), which is approximately the size of a human hair. These small cutters can make very small detail possible in a wide range of applications.

Water jet is considered a "green" technology. Water jets produce no hazardous waste, reducing waste disposal costs. They can cut off large pieces of reusable scrap material that might have been lost using traditional cutting methods. Parts can be closely nested to maximize material use, and the water jet saves material by creating very little kerf. Water jets use very little water (a half gallon to approximately one gallon per minute depending on cutting head orifice size), and the water that is used can be recycled using a closed-looped system. Waste water usually is clean enough to filter and dispose of down a drain. The garnet abrasive is a non-toxic natural substance that can be recycled for repeated use. Garnet usually can be disposed of in a landfill. Water jets also eliminate airborne dust particles, smoke, fumes, and contaminates from cutting materials such as asbestos and fiberglass. This greatly improves the work environment and reduces problems arising from operator exposure.

Versatility

A water jet cutter creating a specialist tool

Because the nature of the cutting stream can be easily modified the water jet can be used in nearly every industry; there are many different materials that the water jet can cut. Some of them have unique characteristics that require special attention when cutting. Each material cut will have some unique characteristics that have to be taken into account.

Materials commonly cut with a water jet include rubber, foam, plastics, composites, stone, tile, metals, food, paper and much more. Materials that cannot be cut with a water jet are tempered glass, diamonds and certain ceramics.

Water jet cuts are not typically limited by the thickness of the material, and are capable of cutting materials over eighteen inches (45 cm) thick. The penetrating power of these tools has led to the exploration of their use as anti-tank weapons but, due to their short range and the advent of composite armour, research was discontinued.

Availability

Commercial water jet cutting systems are available from manufacturers all over the world, in a range of sizes, and with water pumps capable of a range of pressures. Typical water jet cutting machines have a working envelope as small as a few square feet, or up to hundreds of square feet. Ultra-high pressure water pumps are available from as low as 40,000 psi (276 MPa) up to 90,000 psi (621 MPa).

Process

There are six main process characteristics to water jet cutting:

Uses a high velocity stream of abrasive particles suspended in a stream of Ultra High Pressure Water (30,000 - 90,000 psi) which is produced by a water jet intensifier pump.

Is used for machining a large array of materials, including heat-sensitive, delicate or very hard materials.

Produces no heat damage to workpiece surface or edges.

Nozzles are typically made of sintered boride.

Produces a taper of less than 1 degree on most cuts, which can be reduced or eliminated entirely by slowing down the cut process.

Distance of nozzle from workpiece affects the size of the kerf and the removal rate of material. Typical distance is .125".

Temperature is not as much of a factor.

Edge quality

Edge quality for water jet cut parts is defined with the numbers 1 through 5. Lower numbers indicate rougher edge finish; higher numbers are smoother. For thin materials, the difference in cutting speed for Quality 1 could be as much as 3 times faster than the speed for Quality 5. For thicker materials, Quality 1 could be 6 times faster than Quality 5. For example, 4 thick Aluminum Q5 would be 0.72 ipm (18 mm/min) and Q1 would be 4.2 ipm (107 mm/min), 5.8 times faster.

Multi-axis cutting

Main article: Multiaxis machining

A 5-Axis Waterjet Cutting Head

A 5-Axis Waterjet Part

With recent advances in control and motion technology, 5-axis water jet cutting (abrasive and pure) has become a reality. Where the normal axes on a water jet are named X (back/forth), Y(left/right) and Z (up/down), a 5-axis system will typically add an A axis (angle from perpendicular) and C axes (rotation around the Z-axis). Depending on the cutting head, the maximum cutting angle for the A axis can be anywhere from 55, 60, or in some cases even 90 degrees from vertical. As such, 5-axis cutting opens up a wide range of applications that can be machined on a water jet cutting machine.

A 5-axis cutting head can be used to cut 4-axis parts, where the bottom surface geometries are shifted a certain amount to produce the appropriate angle and the Z-axis remains at one height. This can be useful for applications like weld preparation where a bevel angle needs to be cut on all sides of a part that will later be welded, or for taper compensation purposes where the kerf angle is transferred to the waste material - thus eliminating the taper commonly found on water jet-cut parts. A 5-axis head can cut parts where the Z-axis is also moving along with all the other axis. This full 5-axis cutting could be used for cutting contours on various surfaces of formed parts.

Because of the angles that can be cut, part programs may need to have additional cuts to free the part from the sheet. Attempting to slide a complex part at a severe angle from a plate can be difficult without appropriate relief cuts.

Removal of Asbestos Garages or Corrugated Asbestos Roofing Sheets

There is a common misconception that only a licensed removal agency or local authority can remove your tired asbestos garage.  

If you are contemplating replacement of your present prefabricated garage then it is very likely that this building contains asbestos cement or Chrysotile (‘white asbestos’). Asbestos cement normally contains from about 5% of white asbestos by weight.

Asbestos is a naturally occurring mineral which was used within the concrete garage sector up until the late 1980s. Modern concrete garages no longer contain asbestos within their roof structure preferring to use reinforced cement fibre. Neither material can be identified by any markings and only chemical analysis will prove that asbestos is present.

The mere presence of asbestos does not necessarily create a health risk and the removal of asbestos cement sheets is not governed by any regulatory body although it is strongly recommended that you/your appointed contractors adheres to safe working methods.

• Thoroughly douse the material before starting work. You are advised to introduce a suitable wetting agent such as washing-up liquid, into the water before saturation. 
• Operatives are recommended to wear RPE/PPE (Respiratory/Personal Protective Equipment) to protect from inhalation of dust particles.
• Avoid breaking asbestos panels unnecessarily but if this is necessary continue to wet down the area that you are working.

Borehole drilling

The true definition of borehole drilling is, a deep hole drilled into the ground to extract natural water resources. The majority of UK homes do not have their own water supply, meaning it is mandatory to pay water companies for the privilege of using the water that they supply to us. However it is possible to have your own water supply meaning a minimisation of costs for water use.

With the cost of water use rising and set to rise further, many businesses worldwide are beginning to think of new ways of accessing water. The worldwide water supply is dwindling and as a result of this, water companies will have to raise the cost of using water due to the fact that water will be seen as a precious commodity. Both business and domestic water users believe it or not can have their own water supply.

Borehole drilling companies offer a way of accessing fresh water direct from the earth's core for business or domestic use.  Many countries such as Ghana in West Africa are using this method and as a result are saving significant amounts when it comes to water costs. Borehole drilling makes it possible to create water pumps and water wells for the supply of fresh clean water, eliminating the need to purchase spring or mineral water as well as taking away the need to boil or filter water. This alone is an instant money saver.

Agricultural businesses such as farms vegetable and fruit producers can benefit from having their own water supply. Many people especially domestic home owners might be sceptical or hesitant to create their own water supply because of the initial outlay. However the initial outlay could be considered an investment in future savings. Some may not see the benefits of borehole drilling, however it is worth noting that some borehole drilling companies have reported that customers have recovered the initial monetary spend within a matter of months. The more water used, the more money saved, seems to be the mantra. Businesses will be more likely to make massive savings. Having said this though domestic users can still make significant savings when it comes to water bills.

Borehole drilling is not as widespread as it could be, although many borehole drilling companies have been running for decades catering mainly for the business market. Domestic users are slowly beginning to see the money saving potential of having their own water supply. Especially with the facts in hand, that within the next few years many domestic users are going to see a 30 percent rise in their overall water bills.