The Long-term Deformation Analysis Of Idle Foundation Pit In Kunming

With the deepening of China’s urbanization process and propulsion,urban underground space to get unprecedented development,foundation pit engineering was proliferated.The foundation pit construction is bound to break the equilibrium of initial stress state,and result in the displacement of soil,making impact on surrounding environment.The supporting of foundation pit is a temporary support structure,its design life is shorter.In the process of construction,because of capital shortage and design changes make project was forced to temporarily shut down,and make it eventually form idle foundation pit.The soil function,precipitation consolidation creep.wet and concrete creep are the important reasons of that foundation pit excavation has time effects.The time effects of idle foundation pit make a great influence on the surrounding environment.The paper makes a complex deep foundation pit in KunMing as the research object,Through the establishment of three dimensional numerical model for analysis the deformation of foundation pit,According to the results of analysis,putting forward the reinforcement technique measures.Finally,making the numerical software to analyze the reliability of the reinforcement measures.The main research contents are as follows:(1)Adopted to numerical software to establish the 3d model and simulate the excavation process.Then combined with field monitoring data to verify the reliability of the numerical software.(2)Analyzing the mechanism of long-term deformation about idle excavation from the sides of soil creep,humidity,precipitation consolidation and creep of concrete.Determining the calculation method of strength parameters about the soil and the concrete.(3)Determining the strength parameters of the soil and the concrete about idle excavation.Adopting the numerical software to establish the 3d model,and analyzing the influences bout the long-term deformation of idle excavation to of the sub-way.(4)Analyzing the security risks about foundation pit and environment.Then combined with the results of investigation and putted forward some reinforcement measures.Finally,making use of the numerical software to analysis the effectiveness of reinforcement measures.