The effect of anchor post-tensioning on the behaviour of a double anchored diaphragm wall embedded in clay

摘要

A proper lateral support system is an important part of any deep excavation to lower the risk of damaging any adjacent structures, utilities or roads. For deeper excavations, the use of either strutted or anchored walls becomes necessary to decrease the amount of wall movement. The use of post-tensioned anchors further limits the amount of ground movement for both temporary and permanent structures. This paper investigates the effects of varying the post-tensioning ratio on the behavior of a double anchored diaphragm wall retaining clay of different consistencies (medium stiff, stiff and very stiff). A parametric study on the behavior of a 10-m deep excavation with two levels of anchors is considered. The analyses are conducted using the two-dimensional finite element program PLAXIS Version 8.2. The study examines the variation of wall horizontal displacement, and bending moment and ground surface movement to provide guidance for different values of the post tensioning ratio.