考虑超固结效应的不同温度路径下饱和粉质黏土的热固结

Thermal consolidation of saturated silty clay considering overconsolidation effect with different heating-cooling paths

通过室内试验,研究了超固结比OCR对不同温度路径下中空圆柱饱和粉质黏土热固结特性的影响。研究表明,同一升温过程、不同超固结比试样所产生的最大孔压基本相同,但在相同的降温过程中,随着OCR的增大,产生的负孔压的绝对值有增大的趋势;升温或降温过程产生的体应变随着OCR的增大而减小,呈指数形式变化,并且温度幅度越大,这种变化幅度也越大;经过升温-降温过程后的最终体应变也随着OCR的增大而减小;升温或降温到同一温度值,其过程设置的温度等级越多,固结体应变也越大,并且随着OCR的增大,不同等级之间的体应变差值减小,而OCR对不同等级升温-降温后的最终体应变间的差值影响较小。

The effects of over consolidation ratio （OCR） on thermal consolidation characteristics of hollow cylindrical saturated silty clay with different heating-cooling paths are discussed by laboratory tests. Given the same thermal loading, pore water pressures of samples with different OCR values caused by heating are almost the same, while the absolute value of negative pore water pressure caused by cooling increases with the increase of OCR value. The consolidation volumetric strain induced by heating or cooling decreases with the increase of OCR value, and the decrease can be described by exponential function. The amplitudes of the change increase with the increase of thermal loading. Besides, after a heating-cooling process circle, the final volumetric strain also decreases as OCR value increases. The volumetric strain is different under different temperature paths. Generally speaking, the more stages during heating or cooling to reach the final temperature, the larger the volumetric strain is. The difference in volumetric strain between different heating or cooling stages to the final temperature decreases with the increase of OCR value, while the OCR value has relatively small influence on the final volumetric strain after a heating-cooling process circle.