采用刚性抗滑桩加固沿软弱结构面滑动的边坡时,桩后土体会逐渐形成一个三维滑动土楔,作用于桩上的极限滑坡推力(Pult)就转化为滑动土楔所产生的被动土压力。本文以更符合实际的对数螺旋线面代替应变楔(SW)模型中直线型滑楔底面,得到改进SW滑楔模型,并基于倾斜薄层单元法,引入智能优化法-粒子群优化(PSO)算法计算Pult。最后还探讨了桩位、桩径以及土体参数变异性对Pult的影响,结果表明:当桩间距较大,桩位设置在坡的中部时,作用于桩上的极限滑坡推力Pult小于按规范推荐的传递系数法所得计算结果,而且Pult与桩径基本上呈线性关系。根据对土体参数不同变异系数进行抽样计算,可得到Pult的变异系数δPult,由此法得到的δPult结果可直接用于刚性抗滑桩可靠性分析计算。
Soil behind the pile would form a three-dimensional sliding soil wedge when landslide occurred along a weak level was reinforced by anti-slide rigid pile.Then,ultimate landslide thrust acting on the pile(Pult) become the passive earth pressure generated by the sliding soil wedge.The modified SW model was established by substituting the more realistic logarithmic spiral surface for the linear sliding wedge underside assumption in the strain wedge(SW) model.Then,the intelligent optimization method-Particle Swarm Optimization(PSO) algorithm was introduced to calculate ultimate landslide thrust Pulton basis of the inclined thin-layer method.Finally,the influences of pile location,diameter and variation coefficients of soil parameters on ultimate Pultwere discussed.It is found that Pultcalculated by the proposed is smaller than that calculated by transfer coefficient method of the code when the pile spacing is large and the pile position is set as the middle of the slope.Moreover,the relationship between the pile diameter and Pultis liner.Furthermore,the variation coefficient(δPult) of Pultcan be obtained by the sampling calculation of the variation coefficient of soil parameters.And δPultcalculated by the above method can be directly used in the reliability analysis of the anti-slide rigid pile.