During a concrete wall construction concrete can be poured i

During a concrete wall construction, concrete can be poured into the wall form either continuously or in layers (stages). What is the difference in lateral pressure induced by green (liquid) concrete between the two casting modes? In the latter mode of casting concrete wall, caution must be taken concerning the depth of concrete consolidation (using vibrator). Why?

Solution

In structures like walls, concreting is advisable in layers only, because :

1. In this way, concrete load(weight) increases gradually. This gives time to initial layers to settle and make the lower part act as a base for further concrete layers.

2. Shuttering boards are supported from outside at a pitch(grid/interval/distance) of about 1200 mm...this also necessianece slow/gradual pouring of concrete.

3. Taking in view point 2 above, vibrator should be used precautiously. Other wise it can make the supports loose and in general also higher use of vibrator can cause segregation of Concrete.