自重应力作用下饱和粘土的固结变形特性
Consolidation Characteristics of Saturated Clays under Self-Weight Stress
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摘要: 本文通过离心试验,研究了饱和粘土在考虑土体自重应力作用下的固结变形特性。试验结果表明,离心试验与常规试验相比,两者压缩特性一致,而固结特性差别较大。离心试验求得的固结速率比太沙基固结理论推算的结果要快,而与有限线性应变固结理论推算的结果相一致。从理论和实验两方面说明,常规固结试验中忽略了主体的自重应力水平,用测定的固结系数推算实际较厚软粘土层的固结变形特性,将会过慢的估计固结完成的时间。此外,离心试验比常规试验的固结历时大大缩短,用离心技术可提高固结试验效率。Abstract: Study of the consolidation and deformation characteristics of saturated clay under self-weight by centrifuge model is described. Comparison with conventional odeometer test has shown that the different kind of tests are of the same compression behaviour, but of the different consolidation behaviour. The rate of consolidation derived from centrifuge test is faster than the solution from conventional theory, but agree with the solution by finite linear consolidation theory. It is theoretically and experimentally indicated the time of consolidation will be underestimated when using the coefficient of consolidation to deduce consolidation deformation behaviour of thick clay layers in which the self-weight of soil is neglected. Moreover, comparing with odeometer test, the time required for consolidation by centrifuge test is much shorter. So it offers higher efficiency in consolidation tests.