中文摘要：

高速公路路基岩溶塌陷通常可以采用水平加筋体防治,系统地研究其受力特性及设计理论具有重要的工程意义和实际价值。首先,针对公路路基荷载及岩溶塌陷的特点,分析了塌陷坑上方水平加筋体的受力和传力特性,采用太沙基土拱理论,计算溶洞上方荷载。深入探讨了水平加筋体设计方法,认为锚固段端部加筋体应变及锚固段传力长度是设计中的关键值,且其与锚固段端部加筋体拔出量密切相关。然后,引入水平加筋体与土体界面的线弹性-全塑性模型,由基本方程导出锚固段水平加筋体弹塑性解答,并结合边界条件建立了锚固段端点拔出量及传力长度的解算流程。在此基础上,引入某实际工程计算参数进行分析,将该方法结果与基于全塑性模型的分析结果进行对比,探讨了不同临空段宽度、加筋体刚度、上覆土体高度、界面摩擦角等因素对临空段端部拔出量计算误差的影响,并分析了上覆土体高度与锚固段传力长度之间的关系。由分析可知,基于线弹性-全塑性模型计算的拔出量和传力长度均较全塑性模型计算结果大,某些情况下,传力长度的计算误差高于40%,若采用全塑性模型计算有可能引起较大的误差,导致设计偏于不安全。

英文摘要：

It is of great significant to study the bearing behavior and the design procedure of geosynthetics beneath highway embankment built in karst terrain as a treatment to sinkhole.Firstly,the load and load transfer in geosynthetics are investigated according to its characteristics;and the Terzaghi＇s soil arch theory in ideal soil is introduced to evaluate the upper load.The strain in geosynthetics and anchorage length are considered as two key design values,which are related to pull-out length at tip of anchorage segment.Then,the linear elastic-fully plastic model is introduced;and the corresponding analytical solution is deduced by the basic equation.The calculating procedures of the lengths of pull-out and load transfer are established by combining the boundary conditions.Based on these,an example in engineering practice is analyzed with its parameters;and the result calculated by proposed method is compared to that calculated by the method based on fully plastic model.The errors influenced by the width of the hole,the stiffness of the geosynthetics,the height of the upper soil,the friction angle on the interface of the soil and the geosynthetics are studied;and the relationship between the length of load transfer and the height of upper soil is investigated as well.The results indicate that,both the length of pull-out and that of load transfer calculated by the method based on the fully plastic model are larger than that by the proposed method;and the error of the length of load transfer is over 40% in some cases.The design base on the fully plastic model may cause unsafe of engineering.