牵引式滑坡推力计算方法研究

Study of calculation method of retrogressive landslide thrust

三峡工程运行期间引发大量库区滑坡地质灾害,由于库区水位及降雨等联合影响,使得牵引式滑坡在库区滑坡中占有相当的比例。通过对库区牵引式滑坡形成机制研究,根据变形破坏模式,把牵引式滑坡分为牵引区(初始滑动区)和被牵引区,分析牵引式滑坡在演化过程中牵引区滑体与被牵引区滑体之间的相互依存关系,针对其相互作用力学特征建立合理的物理和数学力学计算模型,初步推导牵引式滑坡推力计算公式,为抗滑桩设计提供合理的设计推力。以三峡库区朱家店牵引式滑坡为例,在确定被牵引区滑体对牵引区滑体存在推力作用情况下,通过推力计算表明,推导出的公式计算得到牵引区滑体的设计推力比单独计算牵引区滑体设计推力更大,相比将牵引区滑体和被牵引区滑体视为整体计算设计推力更小,说明此方法计算的推力用于抗滑结构设计可以达到既安全又经济的效果,为牵引式滑坡治理设计提供新的思路。

During the operation of the Three Gorges Project, a large number of retrogressive landslide geological disaster occurred due to the combined effects of reservoir water levels and rainfall, making the retrogressive landslide occupies considerable proportion in reservoir landslide. Through studying formation mechanism of the reservoir retrogressive landslide, according to the deformation and failure mode, the retrogressive landslide is divided into traction district(initial slide district) and passive traction district, and analyzing the interdependence between traction district and passive traction district during the evolution process of retrogressive landslide. For its interaction of mechanical of characteristics, a reasonable physical and mathematical mechanical calculation model is established; and thrust calculation formula of retrogressive landslide is derived preliminarily to provide reasonable design thrust for anti-slide pile design. Taking the Three Gorges Reservoir Area Zhujiadian retrogressive landslide for example, on the premise of determining exist thrust between traction district and passive traction district, by thrust calculation shows that: derivation formula to calculate the design thrust of traction district sliding body is bigger than calculated the design thrust of traction district sliding body separately, compared traction district sliding body and passive traction district sliding body are regarded as the overall sliding body calculation design thrust smaller, it is show that the method of calculating the thrust for anti slide structure design can achieve both safety and economy effect, so as to provide new ideas for the design of retrogressive landslide.