软基沉降计算中压缩层厚度确定方法探讨

The Method for Determinging Thickness of Compressed Layer in Calculating Settlement of Soft Soil Roadbed

沿海地区平原水网区高速公路的软土路基,其压缩层范围与应力控制法确定的深度通常相差很大,而与应变控制法确定的厚度比较吻合.规范规定的应力控制比值与一些实际情况不符,对大宽度路基条件下的软基不太适用,导致用应力控制法计算出的沉降量比实际沉降大许多.文中结合工程实例,研究出现这一问题的机理,并给出建议.

Generally, the thickness of compressed layer in soft soil roadbed of expressway in the water net region of coastal plain differs greatly from the depth determined by the method of control stress, while it matches relatively with the thickness determined by the method of control strain. The control stress ratio stipulated in the code disagrees with some actual circumstances, isn＇t quite applicable to the soft soil roadbed with large width. As a result, the settlement calculated by the method of control stress is significantly greater than the actual one. Integrating with the practical engineering, the authors investigate the mechanism of this problem, and also offer the corresponding suggestions.