针对目前滑坡推力确定方法研究中存在的问题及滑坡推力特征监测的要求,提出基于BOTDR监测数据确定滑坡推力的计算分析方法.通过在抗滑桩桩体内布置光纤传感器,监测抗滑桩在滑坡推力作用下的连续变形;应用抗滑桩桩身应变、弯矩及抗滑桩受力之间的函数关系,计算作用在抗滑桩上的水平推力.结果表明:利用BOTDR监测数据不但能够确定抗滑桩上作用滑坡推力的分布形式和大小,还能确定整个抗滑桩上的受力及滑面埋深.依据计算结果分析,同一排抗滑桩上的滑坡推力分布具有明显的分段特征,滑坡推力分布形式差别较大,靠近滑坡主轴线的中心段,滑坡推力最大,分布近似抛物线形;边缘段滑坡推力作用最弱,从边缘至中心段滑坡推力方向发生了偏转.
By analyzing the problems of determining landslide thrust at present and requirements of thrust characteristics of landslide, calculation method of landslide thrust is proposed based on BOTDR monitoring data. By arranging optical fiber sensors on anti-sliding piles to monitor their continuous deformation under thrust, landslide thrust was determined based on the function relationship among strain of anti sliding piles, bending moments and force on piles. The results show that this method is not only able to determine modes and values of landslide thrust on anti-sliding pile, but also to determine the force on the piles and the presence of slip surfaces. According to the results of calculation, thrust distribution of the landslide on the piles has segment characteristics. The modes make a great difference. When the piles are close to landslide spindle line, landslide thrust is the largest which has the mode approximate parabola. The effect of landslide thrust on marginal segmentation is weaker. So, from central to marginal segmentation, the direction of landslide thrust generates deflection.