饱和软粘土的流变和循环流变试验研究

Experimental Study on Creep and Cyclic Creep Characteristics of Saturated Soft Clay

分别对上海淤泥质饱和软粘土进行了长期流变和循环流变试验,得出其在不同围压、不同偏压和不同动应力作用下的变形规律。结果显示,围压相同时,偏压比大,试样的流变变形大,而偏压比相同时,围压大,流变变形也大;循环流变试验总体规律和流变试验相同,但经过一个循环加载阶段之后,随后的流变变形则很小。这些结论对今后软土地区高速公路、铁路和地铁建设提供一些帮助。

Several long term creep and cyclic creep tests of Shanghai soft clay are performed in the laboratory. Test results have been obtained under various combinations of confining stresses, deviation static stress ratios and deviation cyclic stress ratios. The results reveal that the axial creep strain increases with the increase of deviation static stress ratio under a constant confining stress, while it also increases with the increase of confining stress under a constant deviation stress ratio. Such a phenomenon is similar to that from the cyclic creep tests, but the following creep strain increase will be significantly reduced after a period of cyclic loading. The results will benefit the expressway, railroad and underground constructions.