ABSTRACT
Major cross utilities normally pose great difficulties in construction of temporary support wall (diaphragm wall) etc. for underground cut and cover tunnels. In Calcutta, during execution of the first metro of the country, at such locations discontinuities in the diaphragm wall were left. These discontinuities in the diaphragm wall were later on plugged by steel plates also called as lagging plate. These discontinuities (lagging zones) had led to serious problems during excavation. Present paper deals with planning in Delhi Metro to tackle such locations to ensure construction of continuous diaphragm wall and avoid related problems during execution.
