韧性锚杆对边坡支护作用的模型试验研究

MODEL TEST OF SUPPORTING EFFECT OF RESILIENT ANCHOR CABLES ON SLOPE

滑坡是世界上分布最广、危害最严重的地质灾害类型。降雨等因素作用下滑坡沿着滑动面发生剪切大变形,造成抗滑结构发生剪切破坏,然而目前抗滑结构设计未能充分考虑滑坡剪切大变形的静态、刚性设计,亟需开展滑坡-韧性锚固体系演化机理的深入研究。本文基于塑性变形理论提出了一种韧性锚固结构,建立了其力学模型,并以开挖后种蜂场滑坡为原型,设计了模型试验,对比分析了有无锚杆加固下边坡体变形、土压力等多源数据变化规律,结果发现:(1)韧性锚杆加固作用下边坡内测点侧向应力分布与曲线形态发生显著变化,边坡抗滑力增大了20%。(2)边坡剪切大变形过程中,韧性锚杆轴力呈周期性变化,与理论相符。(3)韧性锚杆明显减少了边坡位移及变形破坏范围,滑动范围减少了约25%。

Landslide is one of the most widespread and serious geological hazards in the world.Under the effect of rainfall and other factors,the landslide moves along the sliding zone,which causes the shear failure of reinforcement structures.However,the design of reinforcement structures has not been considered the dynamic evolution of the landslide and co-deformation between landslide and structures.So it is urgent to carry out the evolution mechanism of landslide with resilient anchor cables.Based on the theory of plastic deformation,a resilient anchor cables structure is proposed in this paper,and its mechanical model is established.The model test is designed by taking the Zhongfengchang landslide as the prototype.The axial force of the anchor cables,slope deformation and earth pressure are recorded during the deformation process.The results show that:(1)The soil pressure distribution and evolution of the reinforced model are completely different from the unreinforced model.Under reinforcement of resilient anchor cables,the resistance of the slope is increased by 20%.(2)In the model test,the axial force value of anchor cables changes periodically in the working stage,which is consistent with the theory.(3)Resilient anchor cable obviously decreased the displacement and deformation area of the slope.