DIAPHRAGM WALL SUPPORTED BY GROUND ANCHORS AND INCLINED STRUTS: A CASE STUDY

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.