寒区裂隙冻岩隧道岩-水-冰力原位测试及冻胀力模型

为了研究寒区裂隙冻岩隧道冻胀力并建立合理的计算模型，以川藏公路雀儿山隧道为工程依托，组合利用水压力计、土压力盒和多点铂电阻温度传感器进行冻胀力原位测试，考虑静水压力，提出了裂隙成环贯通原位冻胀时的隧道宏观冻胀力理论模型，并将计算结果与原位测试结果进行了比较分析。研究结果表明：现场原位测试方法考虑了岩-水-冰在冻结过程中随时间和温度的变化特征，避免了对裂隙岩石细观结构模型的讨论，方案合理且易于实施；裂隙岩石冻结前水压力随径向深度增加而线性减小，径向1.5～2m围岩内裂隙水挤出形成急剧增压区间，靠近结构处水压力降到最低；原位测试得到冻胀压力0.615～3.355MPa，空间分布以拱顶处最小，拱腰处最大，冻胀力模型计算得到的冻胀压力约0.46MPa，去除水压力，裂隙成环贯通宏观冻胀力理论模型计算结果接近于工程实际。

Frost heaving force computational model of tunnel with frozen rock containing #br# fissures and rock- hydraulic- ice pressure in situ test in cold region

To investigate the frost heaving force and build a reasonable calculation model of the fractured rock tunnel in the cold region, taking the Queer shan tunnel in the project of North line of Sichuan-Tibet highway as a case study, the water pressure gauge, the soil pressure box and the multi-points platinum resistance temperature sensor was carried out to test the frost heave force in situ. Considering the hydrostatic pressure, a theoretical model of the frost heaving force in a circular crack tunnel is proposed at the macro level. Finally, the calculation results are compared with the in-situ test results. The results show that the in-situ measurement for frost heaving force is reasonable and easy to implement,owing to considering the rock-water-ice in freezing process along with the change of time and temperature characteristics and avoid the discussion on the fractured rock mesoscopic structure model. And the water pressure test shows that the hydrostatic pressure decreases linearly with the increase of radial depth before freezing of fractured rock, and the water in the cracks is forced out and and formed a pressurized zone in the surrounding rock with radial direction of 1.5-2m. Meanwhile,the hydrostatic pressure is decreases significantly and to the minimum near the structure. The frost heaving pressure is 0.615～3.355MPa by the in-situ measured ,with the smallest at the vault and the largest at the hance. The frost-heaving pressure is about 0.46MPa calculated by the theoretical model. Therefore, after removing the water pressure, the calculation results by the theoretical model of the macro frost heaving force of the circular crack are close to the engineering practice.