谢敏 钟素娟

摘 要：对福州可门港原状软土进行一维固结压缩和界限含水率试验。得到了福州地区滨海软土由弹性状态向塑性状态变化过程中其固结屈服应力、压缩模量、液限、塑限与土层深度的关系，对试验结果进行分析可知，福州软土的固结屈服应力随着土层深度的增加而增加，不同深度的土样，其固结屈服压力和有效上覆压力相差不大，超固结比OCR在1附近，但土样的压缩模量、液限、塑限与土层深度关系不大。

关键词：软土；固结屈服应力；压缩模量；OCR塑限

中图分类号：TU447 文献标志码：A 文章编号：2095-2945（2018）33-0062-03

Abstract： One-dimensional consolidation compression and limited water content tests of undisturbed soft soil in Fuzhou Kemen Port were carried out. The relationship between the consolidation yield stress， modulus of compression， liquid limit， plastic limit and the depth of soil layer in the process of changing from elastic state to plastic state of coastal soft soil in Fuzhou area is obtained. The consolidation yield stress of Fuzhou soft soil increases with the increase of soil depth. There is little difference between the consolidation yield pressure and effective overburden pressure of soil samples with different depth. The over-consolidation ratio OCR is about 1. However， the modulus of compression， liquid limit and plastic limit of soil samples have little to do with the depth of soil layer.

Keywords： soft soil； consolidation yield stress； modulus of compression； OCR plastic limit

1 概述

福州可门港属滨海软土地区，该地区存在较大厚度的淤泥软土层。本文通过对福州地区软土进行一维固结压缩试验和界限含水率试验，以期获得福州地区滨海软土在荷载作用下由弹性状态向塑性状态变化过程中其固结屈服应力、压缩模量、液限、塑限、与土层深度的关系，研究结果可为滨海地区软土的力学特性提供参考。

2 一维固结压缩试验

一维固结压缩试验采用杠杆式标准固结压缩仪。竖向荷载施加等级为3.125kPa～1600kPa。

由于传统的Casagrande法确定原状土的固结屈服应力容易失真等缺点，Butterfield首次提出来将e-lgp半对数坐标转换为ln（1+e）-lgp双对数坐标来描述土的压缩性，双对数坐标可以用两条直线很好的表示土体屈服前后的压缩曲线，两条直线交点对应的应力为先期固结屈服应力（固结屈服应力）。许多国内外学者已通过大量试验验证双对数法确定原状粘土固结屈服应应力的有效性[1，2]。……