斜坡软弱地基路堤双指标设计体系

Double criterions design system of embankment over sloped weak ground

为准确获取斜坡软弱地基变形和路堤稳定性的内在联系,运用弹塑性有限元法,建立斜坡软弱地基在路堤自重荷载作用下的数值模型,根据弹塑性变形所获的地基变形系数以及剪切强度折减法所获的稳定安全系数,结合渝怀铁路实际工点的现场测试成果,构建了兼顾"变形"与"稳定"的斜坡软弱地基路堤双指标设计体系,并论证该体系的科学性、可操作性,提出该设计体系的实际运用步骤。研究结果表明:兼顾"变形"与"稳定"的斜坡软弱地基路堤双指标设计体系可更真实地反映路堤的稳定状态及变形发展趋势,有效指导工程设计及施工。

In order to obtain the relationship between sloped weak ground deformation and embankment stabilityaccurately, a numerical model of embankment over sloped weak ground was established based on the elasto-plasticfinite element method. The double-criterion design system considering “deformation” and “stability” was putforward according to ground deformation coefficient and safety factor. They were respectively obtained by elastoplasticdeformation and shear strength reduction method with the field test results combined from the Chongqing-Huaihua Railway. The design system is proved to be scientific and operable, and the application steps of the designsystem are recommended. The results show that the stability and the deformation trends of embankment oversloped weak ground could be more truly reflected by the double criterions design system. The engineering designand construction could also be effectively guided by the design system.