Placing in Bags:

In this method, properly concrete filled bags are lowered into water and placed carefully in a header and stretcher fashion as in brick masonry with the help of divers. The method has advantages in that, in many cases, no formwork is necessary and comparatively lean mixes may be used provided sufficient plasticity is retained. A work is slow and laborious, as the accurate positioning of the bags in place can be only accomplished by the divers. The bags and labour necessary to fill and tie them are relatively expensive. This method is only suited for placing the concrete in shallow water. Voids between adjacent bags are difficult to fill. There is small bonding other than that achieved by mechanical interlock between bags.