大气影响下膨胀土包边路堤变形性状研究

Deformation behaviors of medium expansive soil embankment covered by lime-treated soils subjected to weather influence

在中膨胀土包边试验路堤上开挖形成试坑和试样,采用浸水与非浸水两种方式,模拟大气影响下包边路堤土的状态,通过现场直剪试验、载荷试验和室内膨胀率试验,获得路堤土强度与变形性能的对比参数。基于此建立考虑大气影响的路堤模型,利用平面应变有限元方法,计算与分析路面因路基土湿化膨胀和行车荷载作用所产生的不均匀变形,将其与容许值比较后,评价路面结构破坏的可能性,为中膨胀土路堤填筑方案设计提供依据与参考。

By soil samples soaking, the performance of a medium expansive soil embankment covered by lime-treated soil subjected to weather influence is simulated; the variant mechanical and deformation behaviors in soaking and non-soaking statuses are investigated through field direct shear tests, plate loading tests and swelling ratio tests. Based on the above test results, an analytic model of embankment subjected to weather influence is established; then the pavement deformation due to subsoil performance changes under soaking swelling and traffic loading conditions is calculated. According to the comparison between computed differential settlement and deformation allowance, the probability of pavement structure damage is evaluated, which is of referential significance to the design of medium expansive soil embankment.