Numerical analysis of inclined struts and truss structure in excavation stabilization based on the damage potential index (DPI)

In this research, in different conditions, the behavior of the inclined Struts support system and truss guard structure has been investigated. For this purpose, the horizontal and vertical movements of the soil due to excavation and the level of damage of buildings adjacent to these systems are determined to maintain the excavation. Excavation has been studied at three depths of 4, 7 and 10 meters, which indicate shallow, medium and high depth excavation, respectively. Mohr-Columb's behavioral criterion was used for soil behavior. The excavation was modeled in stages with PLAXIS software. Comparing the outputs obtained from numerical modeling, it was concluded that the horizontal and vertical soil displacement in the inclined Struts models is more than the truss guard structure models. The reason is the lack of vertical member and lateral bracing system in the Inclined Struts, unlike the truss guard structure. The values of stress and abutment reactions in the Inclined Struts method were obtained more than the oblique member of the truss guard structure due to the presence of more indefinite degrees in the truss, which causes stress transfer from more paths and less abutment reactions. Finally, based on the damage potential index DPI, it was determined that between the two systems of Inclined Struts and truss guard structure to stabilize the excavation in the vicinity of the neighboring building in urban areas, the safety and strength of the truss guard structure and the use of truss is safer.