. In last post was regarding inspector authority in concrete construction control. We have learned that with the best materials we cannot produce a best even fairly good concrete without right practice. Here We will discuss here about measuring specifications for mixing water to be added to concrete. We are discussing this topic according to ASTM C94/C.
First we will learn, in how much form, water can present or added to particular batch. Here we are listing how mixing water may consist. They are:
2FR Concrete Water Management System specially designed to record flow water to concrete batch that also provide alarm when washing out after pouring concrete is occurred.
1. Water added in the batch mixing
2. Added water in ice form to the batch
3. Water appears from the moisture, present in aggregate in its surface.
4. Equivalent water from the admixtures
In the mix design we will use the total mass or volume of water from all sources. Surface moisture or admixture equivalent water is derived from standard test and procedure.
Now question is the accuracy in water measurement. The water measured either by mass or volume should have an accuracy of 1% of water that is totally required in mix. The ice added to the mix, in the special situations, should be measured by weight.
Now what about truck mixer? In truck mixing in sometimes there has some amount of wash water in the drum. The retained water that is not discharged to be used for next batching should be measured accurately. In case of where retained water cannot be measured accurately or it is impractical to measure this water, it is wise to discharge all water before loading materials for next batch. The total water, including above discussed wash water, should be measured and weighed in an accuracy of 3% of water that are designed for a particular batch.