When the depth of trench is large, or when the sub-soil is loose, the sides of the trench may cave in; this is a serious problem during the construction of a structure. This problem can be solved by adopting a suitable method of timbering. Timbering of trenches, sometimes also known as shorting provides timber planks and boards and thus temporary support is initiated to sides of the trench. For the deep trenches we can follow methods like stay bracing, box sheeting, vertical sheeting, runner system and sheet piling. Stay bracing method is employed for supporting the sides or a bench excavated in fairly firm soil. For loose soils, we adopt box sheeting. Vertical sheeting finds its role in deep trenches in soft ground. For extremely loose and soft ground, runner system is used. Sheet piling is used where lateral earth pressure is more.
No comments:
Post a Comment