What is Concreting?

Concrete is a mixture of cement, coarse aggregates, fine aggregates and water in certain proportions. Islandview Construction makes sure the best quality and workmanship is adhered to and what best methods to suits the customers needs.

The preparation of concrete is done after following specific standard procedures to ensure optimum quality. The main steps used for the manufacturing of concrete are explained as followed:

1. Batching:

The process of precise measurement of concrete ingredients to ensure uniformity of proportions and aggregate grading as per mix design proportions is called batching. Batching may be by volume or by weight.

Batching by Volume

Batching by volume is generally adopted for general construction works and it is carried out by using wooden or steel boxes. In volume batching, bulking effect of sand has to be taken into account.

Batching by Weight

Batching by weight is adopted for important projects and batching plants are used for this purpose. Weight batching is more accurate than volume batching.

2. Mixing:

After precise batching all the ingredients of concrete are thoroughly mixed until the concrete of uniform color and required consistency is obtained. Mixing of concrete may be done manually or mechanically.

Manual Mixing

Manual mixing is adopted for small construction activities. Concrete is less efficient and requires more cement than that required in machine mixing to obtain the same strength.

Machine Mixing

Machine mixing is adopted for general construction works. In this method batch mixers or continuous mixers are used. Batch mixers are either with tilting drum or with non-tilting drum and are available in various capacities. Batch mixers with tilting drum are most commonly used. For general works 10/7 or ¼ cubic yard capacity mixers are used. 10/7 means 10 cubic feet of dry material yields 7 cubic feet of wet concrete. 1-cement bag capacity mixers are convenient and generally used. Mixing time should not be less than 90 seconds.

3.  Transportation:

The process of transferring the concrete from the location of mixing to the construction site is known as transportation of concrete. Transportation may be manual or mechanical.

Manual Transportation 

Manual transportation is adopted for small construction activities or when the construction site is near to the location of mixing.

Mechanical Transportation 

Mechanical transportation through pumps or lifts is adopted for large construction activities or when the construction site is at a considerable distance from the location of mixing. Minimum time should be consumed in transportation to keep the concrete plastic before compaction.

4.  Compaction:

The process of consolidating the concrete after correct placement is known as compaction of concrete. Compaction is an essential step that should not be neglected because the presence of air bubbles or voids in the concrete considerably reduces its strength. 5% air voids in concrete may reduce its strength up to 30%. Compaction may be manual or by mechanical means.

Manual Compaction 

Manual compaction through tempering and rodding is adopted for small and less important concreteworks.

Mechanical Compaction 

Mechanical compaction through vibrators is done for large, important and general concrete works. Vibrators may be placed externally or internally based on the level of compaction required.

5.  Curing:

The process of keeping the concrete moist or wet for certain time period after placing and compaction to complete the hydration process and to gain the required strength is called curing. Concrete made with ordinary and sulphate resistant cements should be cured for at least 8 days, while that made with low-heat cement should be cured for at least 14 days.