Pile Cap Analysis and Design Program from S.E Software

Pile Cap Analysis and Design is a design program that facilitates a foundation engineer to design to design and analysis a cap for Pile group. This is a windows-based and interactive design program of which professional version allows one to arrange piles in positions that align piles accurately or nearly close to provide center of resistance to center load in same axis to avoid eccentricity. This facilitates engineers to read the new position of pile coordinates from this program and to supply piles and pile caps layout to the contractor. This facility followed by the designing the cap at the same time. One can delete and/or add and even he can temporarily disable the influence of any pile in a cap. Manual calculation to input coordinates is not required as the arrangement of piles are pre-programmed. Caps for upto 16 piles in group having various sizes, shape and of different materials like steel, concrete or timber of any capacity can be handled and designed. Just provide number of piles and the pile cap edge with piles in standard layout are drawn. The dropdown menus provide facility to change spacing, concrete strength, edge distance, covering, grout strength, reinforcement, column size and many other relevant parameters.
Pile cap analysis and design program from S.E Software
Besides providing number of piles and layout, it can be calculated the number of piles and necessary alignment from provided axial loads. A cap can be designed for calculated reaction or for maximum capacity of pile. There have either option of entering cap thickness and then check it or calculation of required thickness for pre-defined or pre-programmed alignment/arrangement of piles. Once user has created drawing of pile groups and position of columns and cap edge, he can enter the design loads and the cap can be checked for service condition.
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What is Piling? What is Point of Refusal?

Piling is portion of system of foundation that is pushed into just under the cap into the earth to provide support to the superstructure above. Piling is used in relatively weak shallow strata of the earth where loads from superstructure are transferred through piles to deeper stronger strata. It is often used as foundation repair solution for existing distressed building where foundation sinking, cracking and warping in different structural member are visible, alarming the dwellers of structural failure. The names that are used regarding piles depending on types and uses of them in Geotechnical engineers are :

a. Segmented piling

b. Push piling

c. Pile blocks

d. Steel piling 

Driving pile to point of refusal
e. Concrete piling

f. Double piling

There have other name like grouted pile and drilled pile and different languages and regions of the world also named piles in hundred ways.

In case of piling in sandy soils, friction developed around surface of the piles developed main capacity to the piles. In case of piling in clay soil, the capacity of piles are expected to develop from both wall friction between soil and pile surface and capacity that developed at the tip of pile (end bearing) in a more stable or competent stratum.

Pile Point of Refusal:

This is a point at which level piling operation can no longer be continued into the earth without lifting or breaking the structure above. A lighter structure, as it has less weight, it reaches point of refusal at a relatively shallow depth. A heavy structure, as it is relatively heavier, it attains its refusal point at relatively deeper point so that it reach hard strata or rocks or it have combined or isolated action of   skin friction enough to support heavier loads. It should be noticed that a point of refusal in wet condition is not the same as it in dry condition.
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Expansive Soil Instability of Foundation and Solutions to Avoid Foundation Repair in California

In residential building having relatively lighter structures expansive clay soils cause adverse impact on foundation resulting instability of foundation and foundation repair in this state is very common which involves a lots of money i.e., financial loss to the home owners. So home foundation problem, home foundation settlement or home foundation repair are very common terms in this state to both home owners and foundation repair contractors. Various contractors have made colorful pages in the web seeking quotes and tempting the home owners to inspect their foundations for free.


In the previous posts regarding black cotton soil as well as expansive soils it was discussed many times how expansive soil results failure or settlement to foundations. In this post we discuss possible solution more accurately simple and low cost solution for foundation problems of this type.

Solution for foundation problem:
Sign of home foundation settlement requiring foundation repair

In many places of the world, the home owners consider soil investigation for their small homes is not important. But the main fact is that expansive soil is harmful to the lighter structures having shallow foundation. The established and skill soil investigation firms should be chosen for this purpose. The soil investigation data assist foundation engineers to predict size and depth of foundation (if possible) avoiding top expansive layer if there any. If foundation have to found on expansive soil i.e., there is no way to avoid it, the investigation report provides information to design the foundation to withstand adverse effect of existing expansive soil. This also helps tp provide future maintenance facility if there have any problem.

For structures that are already affected by expansive soils, some foundation solutions are used to strengthen foundation to support foundation and to restrict further movement. This purpose can be served by various methods of underpinning and reinforcing the foundation walls. Underpinning prevents sliding and vertical movement and the later one are used to withstand lateral pressure.

The structures that exist on expansive soil and not yet suffer any adverse effects of expansive soil, soil maintenance is the cheapest and important solution to keep foundation safe. Soil maintenance includes providing and keeping constant and uniform moisture level in the soil. Maintaining uniform and continuous moisture to the soil prevent shrinkage and swelling of such soil. To avoid differential or localized or isolated saturation of soil proper drainage facilities should provide.
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Problem with Pier and Beam Foundation in Texas

Expansive and reactive clay soils generate main foundation problems to lighter residential buildings in all over the world. United States are not an exception in this regard. In Texas, Virginia, California and some portion of Colorado, in United States, this problem is considered the main foundation problem and the home owners kept always busy to find the perfect foundation repair contractor to fix and repair their sweet home.

Texas foundation, foundation settlement

More than 90% of the older homes in Texas were built with pier and beam foundations. Heavy rainfall is very common in Texas especially in northern and eastern portion of Texas State. The excessive rainfall associates the foundation problems in pier and beam houses.

pier and beam foundation The foundation problems include development of cracks in walls and jamming of doors and windows. More over the older homes have no proper drainage to drain water and results accumulation of water or seepage of water towards vertical and lateral directions. The condition becomes worse where expansive clay soil exist beneath building which is very common in Texas. Expansive soil gets expanded with the presence of water and results the piers to heave. When  the clay soil under a pier gets saturated, this pier sunk as soil lacks its ability to support this pier.

Besides this major foundation problem sometimes termite damage, warped beams, decomposed wood in different structural members also make busy home owners to get repaired their foundations.
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Black Cotton Soil

The property of volumetric changes with the change of atmospheric conditions makes black cotton soil dangerous to be founded buildings. It swells excessively when wet and shrinks excessively when dry resulting terrible cracks in soil without any warning. It has a great affinity to water. This tendency of soil is on account of the presence of fine clay particles. Cracks are formed due to movement of the ground on account of alternate swelling and shrinkage. The cracks thus formed are sometimes 15 to 20 cm wide and 2.5 to 4 m deep. The summary for all posts on black cotton soil are listed below:
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Micropile: The Most Common Foundation Solution in Texas

The most common foundation problem are settlement of foundation and basement leak which is visible and sometimes leads to total foundation damage. The foundation repair is very critical, expensive and time consuming task. Sometimes it is almost impossible to repair a particular foundation. So it is very important to select a right foundation or foundation system.

Pile or pile group is a deep foundation that carry load to firm strata beneath foundation. But when a firm stratum lays at a relatively shallow depth but shallow foundation at this depth is not economical and for foundation repair task like retrofitting and underpinning structure micropile technique are adopted.

Micropile is a reinforced replacement pile that is installed by drilling followed by grouting. Typically micropile is designed to be small diameter having dia of less than 300 mm. It can be designed to act like conventional pile to withstand lateral and axial loading or it can be grouped to have combined soil and pile bearing action to support designed loading.

Micropile can be designed as a group of micropiles that the loads directly or closely spaced grids of micropiles of to reinforce the soil mass internally. In the later case they together with the soil form a reinforced composite that supports entire designed loads. In the first case the reinforcement in pile resist almost entire loads. In this post we discuss the fist methods of micropiling of directly loaded.

These piles can be designed as a substitute of conventional piles of medium to large dia to transfer load to relatively stable or firm strata. The loads that come from either axial or lateral sources are supported geotechnically by grout for each pile and structurally by reinforcement in pile. At least 90 percent projects of foundation construction and foundation repair in Texas involve this type of micropiles.
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