Abstract: Based on the results of the roadbed soil through plate loading test，under the environment of the permafrost，the mechanical parameters such as bearing capacity，deformation modulus，shear modulus were analyzed and determined after the roadbed soil experienced a freezing and thawing cycle.The displacement and deformation model of soil was discussed and its correctness was proved.Th e results indicate that the way that the freezing soil are regard a8 a three-dimensional and elastic continuous medium is reasonable.Th e theoretical values of the deformation are agreement with the measuring values.

Key words: Qinghai-Tibet Railway, plate loading test, permafrost

摘要： 基于现场路基填土的载荷试验的结果，分析并确定了在多年冻土区环境情况下，路基填土在经历了一个冻融 循环后的承载力、变形模量、剪切模量等力学参数．并就该土层位移变形模式进行了探讨且检验了其正确性．结果表 明：将冻土理想化为三维弹性连续介质是较为合理的，其位移变形的理论计算值与实测值较为吻合．

关键词: 青藏铁路, 载荷试验, 多年冻土