A Comparison of Performance of Deep Excavation using the Top Down and Bottom Up Methods in Kenny Hill Formation

Abstract

This paper presents the comparison of performance between two deep retention systems using the Top down and Bottom Up methods in Kenny Hill Formation. Both the deep excavations are for the Klang Valley MRT underground stations; namely the Bukit Bintang and Merdeka stations which have similar retained depth of 33.5m and 31m respectively and both having 1.2m thick Diaphragm walls. Both the stations are designed with the same design criteria and factor of safety. The selection of type of retention systems, strutting system, construction sequences and timing and instrumentations are discussed. The predicted and measured diaphragm walls displacements and Strutforces at different stages are then compared and discussed.