对于冻土隧道，当作用于衬砌上的冻胀压力大小不同时，应考虑不同的设防措施，力求达到既安全又经济的目的。以昆仑山隧道为背景，首次提出冻胀力等级划分的标准。研究结果表明：对于单线铁路隧道，深埋条件下冻胀力的等级可通过0.07MPa和0.3MPa两个广义冻胀力值，浅埋条件下可通过0.3MPa和0.7MPa两个广义冻胀力的峰值，作为分界值将冻胀力划作三个等级。

For tunnels in frozen zone, different countermeasures should be considered for the sake of being both safe and economical when different frostheave forces are applied on the tunnel lining. Based on the case of Kunlunshan tunnel, the classification standard of the frostheave force is presented in this paper. The results show that, the frostheave force can be divided into three classes by the following two values for the singleline railway tunnels: 0.07MPa and 0.3MPa for the deep tunnels; 0.3MPa and 0.7MPa for the shallow tunnels.