Analysis On Excavation Effect Of Foundation Pit Of A Riverside Office Building In Soft Soil Area

In recent years,China has been in the boom of real estate investment and municipal infrastructure construction.With the development of cities,the development of underground space in urban areas where land is becoming more and more tight has become more and more common,such as high-rise multi-storey basements,Underground railways and stations,underground parking garages,underground shopping malls,etc.The development and utilization of these underground spaces necessarily involves the excavation of deep foundation pits.Because the foundation pit is not an independent excavation,it is restricted by various conditions,the construction site is narrow,the geological conditions are complex,the construction operation is difficult,and the surrounding site protection requirements are high,which makes the design and construction of the foundation pit project more difficult and safe The production situation is getting worse.How to make the foundation pit project safe and economical has become a subject that researchers are constantly exploring.The main work and conclusions of this article are as follows:(1)By monitoring the deep displacement of the pile,the deep displacement of the soil,the supporting axial force,and the ups and downs of the pillars on the site of a deep foundation pit project near the river in the west of Hangzhou City,the monitoring data during the excavation process were collected,and the data results were analyzed.,Summarize the change law of foundation pit excavation.The results show that the excavation of the foundation pit in the soft soil layer,the displacement of the retaining pile is the largest when the foundation pit is excavated;the river and vehicle loads have a certain effect on the internal force and deformation of the foundation pit structure.(2)Based on the typical profile of the deep foundation pit project,a two-dimensional finite element analysis model of the foundation pit was established using PL AXIS 2D finite element software.The HSS constitutive model was used as the soil constitutive model to simulate and analyze the different conditions of the foundation pit The laws of change of the axial force of the lower support and the displacement of the retaining structure,etc.,and comparing the calculation results of the finite element analysis with the monitoring results of the foundation pit,it can be seen that the results of the analysis using the HSS constitutive model are more consistent with the measured laws.