Shenyang Shimao Wulihe T3-T5and S3Building Deep Foundation Pit Project Analysis

With the rapid growth of China’s construction market and the progress of urbanization, modern buildings, especially the ones built after1980s, see a tendency of both rising high into the sky and extending deep below the ground. Skyscrapers, underground parking lots, civil air defense systems, the rapid growth of the water conservancy projects and subways all require foundation pit engineering, with the depths from5to20meters, some even30meters. With the growth of the numbers, such problems as the pits getting too close to the objects of environmental conservation, the increasing depths, scales, sizes of the pits and compaction of construction sites, etc.According to insufficient statistics, since2005, there have been348real estate development projects involving pit foundation engineering in Shenyang, among which, there are58pits with the depths over15meters. With social and economic development, pits see a trend of going deeper, which brings the problem of the retaining and protecting the deep foundation pits to the fore. This thesis, with the research focus on finding the optimal design alternative for the foundation pits with the depth about20meters in Shenyang, so as to offer some reference to similar projects in the future.The thesis, takes the example of the foundation pit retaining project of Shimao Resident buildings (T3-T5and S3) in Wulihe Area in Shenyang, elaborates on the characteristics of the foundation pits, including the large dimension, close to surrounding buildings, deep excavation, located in downtown area. The thesis compares various foundation pit retaining methods applied nowadays to find the proper one to be applied in this project and then apply these designs to three typical profiles of the foundation pit, to prove the feasibility of the designs through means of deformation monitoring of foundation pits.The thesis reaches a conclusion that the system of applying piles in rows, combining piles with bolts is proper for deep foundation pits retaining projects. The technique of rotary cast-in-place bored filling piles is applied in pile formation. The method of sloping on top of the pit is used to minimize the cost of the project. The system of the neighboring building extends to the pit and badly influences the mechanical holes, which can be solved by artificial boreholes in the affected sections.This article also simulated by finite element method, and the simulated data and the measured data are compared, the result is consistent, according to the monitoring data support, once again proved that the scheme is correct.In conclusion, the thesis put forth a scientific and feasible pile foundation retaining system by analyzing the case of project of Shimao Resident buildings (T3-T5and S3) in Wulihe Area in Shenyang, to offer valuable construction experience for similar projects in Shenyang.