不同人工冻结方向条件下土的冻胀试验研究

为了解决人工冻结施工中的冻胀问题,从工程实际出发,进行不同人工冻结方向以及不同冻结温度模式(恒温和正弦变温)的冻胀试验研究,并对试样的温度场、冻胀量、含水率及干密度等进行对比分析.试验结果表明:在相同试验条件下,正弦变温冻结试样的冻胀量值最小,自下而上恒温冻结试样的冻胀量最大;自上而下恒温冻结、正弦变温冻结和自下而上恒温冻结试样的含水率和干密度变化趋势相同,可知在相同试验条件下,冷端输出的冷能一定时,人工冻结试样内部水分迁移规律将相同.

Test Research on Frost Heave by Artificial Freezing with Different Freezing Directions

Under artificial freezing conditions, including different freezing directions, as well as the constant and sine varying freezing temperature models, the frost heave was studied. The effects of temperature field, frost-heave amount, water content and dry density on the frost heave were analyzed. The test results indicated that the frost heave amount of the top-bottom sine freezing sample was the least and that of the bottom-top constant freezing sample was the most, under the same experimental conditions. The distribution laws of water ratio and dry density of the top-bottom constant/sine-temperature and bottom-top constant temperature artificial freezing samples were the same, which demonstrated that the water migration rules were similar with the same freezing power from cooling side under the same experimental conditions.