The creep characteristics of soft clays have been studied for decades. However, the lateral deformation of soils is not allowed during the commonly used one-dimensional consolidation tests, which cannot describe the real deformation features of soils in practice. On the other hand, the influence of drainage distance on the mechanical properties of soil is still controversial, classified as hypothesis A and hypothesis B. For a better understanding of deformation characteristics of soft clay, especially which in long-terms, a series of conventional oedometer tests as well as novel geometric confined consolidation tests was conducted on soft dredger fill. The results show that the secondary consolidation coefficient of the soil sample C_α would increase firstly, followed by a small decrease with the increase of consolidation pressure generally. C_α would decrease with the consolidation time and also be reduced by preloading. The strain at the completion of primary consolidation would increase with the drainage distance, but the C_α would be affected little. Both compression index C_c and C_α of soft clay would reduce after preconsolidation, in which two parameters show an approximate linear relationship. The creep coefficient of soft clay under the geometric confinement is larger than that under the oedometer test C_αε. However, the trends of the relationship between the creep coefficient and loading are consistent regardless of the confinement conditions.

中文翻译：

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软挖泥船填料随时间变化的变形特性研究

已经研究了软粘土的蠕变特性数十年。然而，在通常使用的一维固结试验中不允许土壤的横向变形，这在实际中不能描述土壤的真实变形特征。在另一方面，排水距离对土壤的机械性能的影响仍有争议，列为假说甲和假说乙。为了更好地理解软土的变形特性，特别是从长期来看，对软挖泥船进行了一系列常规的里程表测试以及新颖的几何约束固结测试。结果表明，在土壤样品的二次固结系数Ç _α通常随着固结压力的增加而增加，然后略有下降。ç _α将与合并时间减少并且还通过预压降低。在主固结结束时的应变将与排水距离而增加，但Ç _α将是受影响不大。两个压缩指数Ç _Ç和Ç _α软粘土的预固结后会减少，其中两个参数示出了近似的线性关系。软粘土的几何约束下的蠕变系数是固结试验下产生大于Ç _αε。但是，无论限制条件如何，蠕变系数与载荷之间的关系的趋势都是一致的。