Analysis Of Retaining Wall Reinforced In Passive Zone Of Soft Soil Foundation Pit

In the pearl river delta, the Yangtze river delta port and other regions, there are alot of soft soil because of the influence of silt deposit. The soil pressure of soft soilpassive area is too small due to improper supporting design in these soft soil area.it isextremely easy to cause over large deformation of retaining structure,and thesurrounding surface subsidence and uplifts, which will seriously affect the safety andnormal use of foundation and adjacent facilities. On the other hand reinforcement inpassive zone can have the strengthening effect in the excavation process. Throughlong-term practice and study,the reinforcement effect is obvious.First, this paper introduces the development of the cement-soil retaining wallengineeringthe current, the deformation mechanism of foundation pit, the earthpressure reseach of foundation pit, the applicable scope of the passive areareinforcement scheme and some relevant research status at home and abroad. on thebasis of the introductions this paper summarizes the affecting factors of the horizontaldisplacement of the retaining wall in soft soil foundation and the retaining wallstress.And then put forward this topic research content and ideas.Secondly, this paper introduces the basic properties of commonly used materialsin reinforcement in passive zone, soil pressure calculation method In the classicaltheory and in model with reinforcement in passive zone, applicable conditions andlimitations of classical stability calculation methods, and selated theory research ofreinforcement in passive zone at this stage.In the reinforcing mechanism analysis, itis necessary to introduce the finite element model for auxiliary analysis.Finally, this paper takes the soil of the model of foundation pit reinforcement inthe passive zone as the research object, uses PLAXIS finite element software toestablish a two-dimensional model of soft soil foundation reinforcement, and thenresearchs the process of soil retaining wall horizontal displacement of excavation, andthe level of soil pressure and other related conten. This paper discusses the changes ofresistance to sliding stability, resistance to overturn stability, passive area soil stresspaths, retaining wall base reaction, retaining wall stress the similarities and differencesand the reasons of their own, and emphatically analyzes the passive area on the stability of retaining wall reinforcement scheme, the effect on the stability of thetranslation, puts forward the following two assumptions:1) The stiffness of soil in passive zone changes when soft soil foundation pitusing reinforcement scheme in passive zone.It leads to change of earth pressuredistribution and passive earth pressure force point up, eventually resistive overturningstability is enhanced.2) After using passive area reinforcement, more soil in passive zone take morehorizontal load under the effect of stress diffusion, which leads to Retaining wallstability enhancement.3) The stress of reinforced retaining wall at the bottom leveli off after takingstrengthening scheme, which is good for its bearing capacity at the bottom of thesafety.