h型抗滑桩滑坡治理中的变形特性及内力研究

Research on the Deformation and Internal Force Characteristics of h-type Anti-slide Piles in Landslide Treatment

伴随着高速公路的快速发展,西部山区由于高填深挖诱发大量的大型和特大型工程滑坡,工程治理的难度和费用逐年增加,且传统单排或多排抗滑桩也无法满足很多工程对变形和稳定性的要求,工程师们经过大量工程实践通常采用能抵御大变形和整体结构形式较好的h型抗滑桩。以贵州省沿德高速公路龙家岩特大型滑坡的h型抗滑桩为研究对象,为了深入了解h型在滑坡治理中的变形规律和内力分布特性,采用传统的深部位移测试手段和先进的BOTDA全分布式光纤传感测试技术对h型抗滑桩在滑坡治理全过程中的变形及内力响应进行测试。分别在h抗滑桩的前、后侧桩及连系梁均布设传感光缆,完整地采集了从滑坡治理过程到稳定后的应变,并结合深部位移成果对h型抗滑桩的变形特性及内力进行研究。研究结果表明:h型抗滑桩治理特大型滑坡的效果显著,从监测结果可知h型抗滑桩形成整体后的一段时间内,滑坡变形收敛,边坡趋于稳定,通过监测桩身变形和应变真实反映抗滑桩的变形和内力的传递规律,对h型抗滑桩的理论及其工程应用具有一定的参考价值,也对光纤传感技术在桩体变形监测中的应用具有一定的借鉴作用。

With the rapid development of Highway,numerous large and super-large landslides appear in western mountainous areas due to high-fill and deep-cut.Engineering difficulties and costs increase yearly,and traditional single-row or multiple-row anti-slide piles cannot meet the deformation and stability requirements of various projects.Through extensive engineering practice,engineers usually adopt h-type anti-slide piles,which are able to withstand large deformations and hold a better overall structure.Taking the h-type anti-slide piles in Longjiayan super-large landslip in Yande highway of Guizhou province as the research object,study has been made on the deformation and internal force characteristics of h-type anti-slide piles though the whole process of landslide treatment by using traditional deep displacement monitoring and the advanced BOTDA distributed optical fiber sensing technology,in order to have a deep insight into the deformation and internal force characteristics of h-type anti-slide piles.Fiber cable has been set on the front and rear piles of h-type anti-slide piles besides the tie beams to completely collect the strain of the piles from the landslide treatment to its stability,and analysis has been made on the deformation and internal force characteristics of h-type anti-slide piles,combining with deep displacement monitoring results.The research shows that h-type anti-slide piles have a remarkable effect on large-scale landslide treatment,and the monitoring results show that the deformation becomes convergent and the slope begins to stabilize within a period after the h-type anti-slide piles work as a whole.By monitoring the deformation of the piles and the strain,deformation and internal force transfer pattern has been truly reflected,which has a certain reference value not only to the theory research and engineering application of h-type anti-slide piles,but also to the application of optical fiber sensing technology in pile deformation monitoring.