Numerical Simulation Of The Character Of Braced Excavation And Its Sensibilities Analysis In Hefei

With the expansion of urban construction and the shortage of urban construction land,the high-rise buildings have entered the people's side.Not only such,high-rise building foundation pit is usually relatively densely populated place in the center of the city buildings.Besides,because of its site working face is limited,complex and changeful environment,brought a lot of trouble to the foundation pit engineering design.And due to the complexity of the foundation pit itself,it is more difficult to support the foundation pit.Pile-interal-strut system is a very important method in deep foundation pit support scheme,because its engineering geological environmental adaptability is strong,and can guarantee the stability and security of the foundation pit,widely used in deep foundation pit supporting engineering.But for concrete of foundation pit engineering,because is affected by many factors,the situation of the foundation pit supporting damage happen occasionally.In this paper,taking a deep foundation pit in Hefei pile-interal-strut system as a example,by using finite element simulation software,on the behavior of deep foundation pit supporting structure is simulated,and the influence of foundation pit character of parameter sensitivity analysis,provide a reference basis for similar projects.The main conclusions of this paper:(1)In the support structure of the piles,the strong system of resistance to pit deformation is formed by the filling pile and the concrete inner support,which has a good effect on the horizontal distortion of the foundation pit.(2)Pile diameter is an important factor affecting the stability of foundation pit.In other conditions,the larger the pile diameter,the better the stability of the foundation pit.However,when the pile diameter exceeds a certain range,the change of the horizontal displacement of the foundation pit will be very small if the pile horizontal distortion continues to increase.(3)The change of pile distance has important influence on the deformation of foundation pit.Under other conditions,the larger the pile distance,the higher the horizontal distortion,the worse the structural stability.(4)By changing the modulus of elasticity,the horizontal distortion of the pile can be effectively affected,but it is not obvious to change the elastic modulus of soil to the moment size of the pile.(5)Cohesion and internal friction angle has little effect on the horizontal displacement and bending moment of foundation pit size.When the cohesion and internal friction angle increase,the horizontal displacement decreases.