Stability Study Of Rigid Retaining Wall Of Sloped Finite Soil Based On Upper Bound Method Of Limit Analysis

Continuous development of urban modernization brings about a variety of space development and utilization and a lot of sloped finite soil occurs.Retaining wall,a supporter of sloped finite soil and one of the engineering structure,analysis of its stability is the basis to ensure a safe application.The traditional stability checking of retaining wall is mostly based on the limit equilibrium method,which needs to solve the earth pressure.However,there is no perfect theory to calculate earth pressure,let alone the earth pressure theory for the liberation of sloped finite soil.On the other hand,due to the shallow buried depth of the retaining wall,the influence of the filling soil in front of wall on the stability coefficient is limited,and the traditional check calculation of the stability of the retaining wall often does not consider its effect.In this paper,the anti-sliding stability and anti-overturning stability of rigid retaining wall with sloped finite soil are analyzed respectively based on the upper limit method of limit analysis.Then,the influence of the filling soil in front of wall on the stability of retaining wall is considered,and the calculation formula of stability coefficient is derived.This method avoids solving the earth pressure.(1)The retaining wall translation mode is studied.In this paper,the retaining wall and filled soil behind retaining wall are seen as a whole to stability.The critical depth of plastic soil behind the retaining wall is calculated.The velocity field is constructed and solved.Side lengths needed in the subsequent calculation are used and soil cohesion,friction angle of soil,overload,critical depth and bottom angle are taken into consideration.All external forces in the overall power and internal energy dissipation power are calculated,energy balance equation is established and sliding stability coefficient acquired directly through the energy method.The analysis process of anti-overturning stability coefficient of retaining wall in rotational mode is similar to that in translation mode.While the soil behind the wall should be regarded as numerous rigid soil strips and calculated by calculus in the calculation of external work and internal energy dissipation.(2)The retaining wall translation mode and the rotation mode are discussed respectively on the basis of above analysis and with the filling soil taken into consideration.Based on the maximum limit analysis method,the filled soil behind retaining wall,wall and wall before filling are seen as a whole and its stability is analyzed.Two adjacent blocks velocity fields are reconstructed and calculated,the soil wall before the work force is increased and the internal energy dissipation is calculated.The stability coefficients of retaining walls under two conditions are derived.(3)The calculation method of the stability coefficient is compared with the existing code to verify the rationality of the proposed method.Within the limited width,the increase of slope angle,the wall before and after filling soil interface friction,angle of internal friction before wall and after wall filling soil,angle of friction in the bottom of the wall,wall before and after the soil cohesion,the wall before and after filling soil interface cohesion,soil cohesion in the bottom of the wall of advantage benefits the stability of retaining wall.The increase of finite width does harm to the stability of the retaining wall,and the value of stability tends to be stable.The calculation results of anti-slip stability in this paper are in good agreement with the specification.With the increase of filling soil before the wall,the results of the two stability calculations are obviously larger than those without considering it.