2D FINITE ELEMENT MODEL TO UNDERSTAND THE BEHAVIOUR OF DEEP EXCAVATION WITH DIAPHRAGM WALLS AND STRUT MEMBERS

Due to the soil’s low strength and high sensitivity to deterioration, designing and building in soft soil is extremely challenging and can result in structural damage. Insufficient space in urban areas has presented a challenge to excavate deep into the earth, and it is increasing the required area for the provision of public services. The function of the diaphragm wall and supporting strut member was modeled in this study using a 2D Finite element model developed with PLAXIS2D software. The excavation was designed to stabilize and limit aging due to excavation at acceptable levels nearby buildings. The analysis took into account the soil’s indirect conduct using the Mohr-coulomb failure method. Results of the study show that up to the depth of 8 m the ground surface can be safely excavated without any structural support. Beyond this limit, soil failure occurs due to the release of vertical stress and loss of lateral support. The diaphragm wall with two strut systems is sufficient to restrict ground movement under structure loading by providing lateral stability to excavation sides. The performance of the diaphragm wall is independent of the cross-sectional shape of strut members. However, the I section is more economical.