【作者】 杨磊；

【导师】 毛坚强；

【作者基本信息】 西南交通大学 ， 岩土工程， 2017， 硕士

【摘要】 抗滑桩作为治理滑坡的有效工程手段,在实际工程中得到了广泛应用。在双排抗滑桩的设计中,如何确定前、后排桩受到的滑坡推力大小是进行设计的关键,但目前尚无较好的计算方法。通过对抗滑桩及前、后排桩间土进行受力分析可知,抗滑桩受滑坡推力作用后发生变形并挤压桩间土体,因此抗滑桩的位移应与桩间土体位移相等,故可利用此变形协调关系求解抗滑桩所受滑坡推力的大小。因此需对抗滑桩的位移计算方法和滑体位移计算方法进行研究。为此,本文的主要研究内容和取得的成果如下:(1)对目前抗滑桩的受力计算模型进行改进,提出了采用"m法"模型模拟桩前滑体对桩的抗力的计算方法。分别对桩在滑面以上、以下的部分建立计算方程,应用幂级数法解得其位移及内力的表达式,再利用桩的上、下段在滑面处的变形协调条件,求得该截面的弯矩和剪力,最终得到整个桩的变形和内力以及桩、土之间的作用力。(2)假定滑坡中滑体应力分布形式,利用弹性力学中的应力函数法,推导出了滑体的应力场计算公式,并进一步推得滑体的位移场计算公式。为利用抗滑桩与前、后排桩间土体的变形协调关系求解抗滑桩所受滑坡推力大小奠定了基础。(3)提出"分担比"(抗滑桩受力占总的下滑力的比值)的概念,通过前文提出的方法计算出了前、后排桩间土体的位移和后排抗滑桩的位移,利用后排抗滑桩位移与桩前土体位移相等的关系,建立起了分担比的求解方法,进而求解出了后排桩所受滑坡推力大小。解决了抗滑桩所受滑坡推力计算方法的问题,从而可对前后排桩分别进行计算。(4)将上述方法应用到一实际工程中,对双排抗滑桩进行了设计计算,以验证所提出方法的可行性。更多还原

【Abstract】 As an effective engineering mean to mitigate the landslide disasters,anti-slide pile has been widely used in practical engineering.In the design of double-row piles,how to determine the magnitude and distribution of the landslide thrusts on the front and back of the piles is the key to the design.However,there is no better calculation method at present.By analyzing the forces on the anti-slide pile and the sliding body between the front and back row,it can be found that the displacement of the anti-slide pile should be equal to the displacement of the sliding body between the piles.Therefore,it is necessary to research the methods to compute the horizontal displacement of anti-slide piles and the displacement of sliding body.The main contents of this paper and the results are as follows:(1)An improved method is developed,in which m-method model is employed to represent the interaction between landslide body and pile.The equations for the part of pile above and under slip surface are constructed respectively,and the expressions of displacements and internal forces are solved with power series method.The bending moment and shear force at slip surface can be obtained by using the consistent conditions of deflection and slope of the pile,and then the deformations,internal forces of the pile and the interaction between pile and landslide body can be computed readily.(2)By assuming the stress distribution of the sliding body in the landslide,the calculation method of the stress field of the sliding body was derived by using the Airy stress function method in elastic mechanics.The formulas of the displacement field of the sliding body were obtained by the geometric equation and generalized Hooke’s law in elastic mechanics.It establishes the foundation for solving the anti-slide pile’s thrust by using the deformation coordination relationship of anti-slide pile and the sliding body between the piles in front row and back row.(3)A concept of "sharing ratio"(the ratio of the force of anti-slide pile to total sliding force)was developed,and the displacement of the soil and the back pile can be calculated by the method proposed in the previous paragraph.By using the deform coordination relationship of anti-slide pile and the sliding between the front and back piles,a method was established to compute the "sharing ratio".Moreover,the thrust on the back row pile can be solved.Then the deformation and internal forces of front pile and back pile can be calculated easily.(4)Applying the method to an engineering example,good results were obtained,which verified the feasibility of the proposed method.更多还原