DIAPHRAGM WALL SUPPORTED BY GROUND ANCHORS AND INCLINED STRUTS: A CASE STUDY
Keywords:Deep excavation, Diaphragm wall, Ground anchors, Inclined struts, Plaxis 2D
Diaphragm wall is one of the options to support deep excavation for the construction of
basements in an urban area having constraints of space due to nearby structures. The subsurface conditions and
nearby existing structures generally decide whether the diaphragm wall will be cantilever or propped. Here is
a case study on a diaphragm wall for Qatar Industrial Manufacturing Company Building that comprises of 4
basements, ground floor, mezzanine, podium, and 38 floors. The planned excavation depth for the four
basements was 15.95m. The subsurface ground consisted of made ground/fill material, Caprock, Simsima
Limestone, Midra Shale and Rus formation. Plaxis 2D software was used to analyze the diaphragm wall. The
analysis results showed that ground anchors were required to limit the deflection of the wall within the
allowable deflection. Moreover, due to unavailability of foundation details for neighbor building, the ground
anchor option was dropped, and inclined steel struts were considered, only in that section. As the inclined steel
struts were supported by pile foundation, therefore lateral load analysis was performed through LPile software.
Staad Pro. software was also used to analyze the waler beams. The target points at the top of the diaphragm
wall were monitored through Total Station equipment to measure the horizontal deflection of the wall.