K_0等比固结条件下软土的变形

Deformation of soft soils under constant stress ration consolidation with K_0

软土的变形与长期变形是学术界和工程界共同关注的问题,会导致软弱土层的过大沉降和工后沉降。软土地基的固结状态更符合K0等比固结状态。基于土体的一维固结理论,针对广东汕头东部围海造地吹填地基进行了原状土样在K0等比固结条件下的固结与次固结特性研究,并与侧限压缩试验结果进行了对比。试验结果表明,K0等比固结条件下试样有明显的瞬时变形特征,并对之后的变形产生影响,与侧限压缩试验结果相比,压缩指数增大、压缩模量减小、次固结系数减小、主次固结时间的分界提前。

The deformation and long-term deformation of soft soils are concerned both in academic and engineering fields, and they lead to the excessive settlement and post-construction settlement of soft layers. Based on one-dimensional consolidation principle, the tests on the constant stress ratio consolidation with K0, which is more actual consolidation state of soft foundation, are carried out to study the primary and secondary consolidation characteristics. The undisturbed samples used are obtained from a dredger fill foundation in Shantou of Guangdong province. By comparing with the K0 confined compression tests, it is noted that the instantaneous compression is significant in the tests on the constant stress ratio consolidation with K0, which affect the primary and secondary deformations. There are higher compression index, lower compression modulus and lower secondary consolidation coefficient than those in K0 confined compression tests, and the duration of the primary consolidation is shorter.