Analysis of Retrofitting Technique of Deficient Foundation by Underpinning by Micropiling: A Critical Review

Abstract

Foundation is an important structural member of a building as it transfers all the structural loads to the ground safely and uniformly so that no stress concentration will occur anywhere in the building. So the foundation of the structure should be designed properly as per the codal provision and maintained according to the structural modification. But when the structural modification occurs in the form of extension of the building horizontally or vertically it becomes necessary to modify the foundation due to the additional load. But some people don’t consider the foundation as a structural element and hence they don’t modify the foundation according to the modified structural requirement. It results in the deficiency of foundation in the terms of reduction of bearing capacity and settlement of foundation. For these deficient foundations retrofitting is needed so that the deficiency can be minimized. In this work the case of vertical storey extension has been taken and deficiency of foundation has been calculated. A retrofitting technique has been discussed which can be applied for the deficient foundation i.e Underpinning by Micropiling. This technique has been applied on the foundation and hence retrofit effectiveness of the technique has been assessed.