季节性冻土区边坡支护结构往往受冻融循环作用而发生破坏，对边坡支护结构造成很大的安全隐患。结合兰州地区某实际工程，应用大型非线性有限元软件ADINA中的热-流体-固体耦合分析模块建立了季节性冻土区土钉边坡支护结构的有限元模型，开发了土体在冻胀、融沉时的本构模型，并用实测结果考证了程序的有效性。然后采用二次开发的软件分析土钉边坡支护结构在冻融循环作用下的反应特性及规律。分析结果表明：在冻融循环作用下，每层土钉钉头附近轴力值增加最大，沿土钉轴向增加值逐渐减小；轴力相对增量沿坡高逐渐增大；水平位移、坡顶地面沉降量均因冻土融化使得含水率增加而突增。研究结论可为季节性冻土地区边坡支护的设计和施工提供参考。

Freezing-thawing cycle in seasonal frozen soil region frequently damages the slope protected by soil nailing structure and threatens the slope retaining structure. In this paper, a finite element model was established using the thermal-fluid-structural coupling module in the nonlinear finite element software ADINA as case study of a project in Lanzhou. A constitutive model was developed to solve freeze-heave and thaw-subside. The program was verified by measured results. The structural characteristic response of soil nailing structure under freezing-thawing cycles was analyzed by the software secondary development. The results show that the increment of axial force of soil nail in each layer reaches a maximum at the nail head and decreases gradually along the axial direction under freezing-thawing cycles. The relative increment of axial force increases with the slope height. The horizontal displacement and ground settlement increase due to melted frozen soil. These conclusions provide significant references for design and construction of slope retaining structures in seasonal frozen soil region.