固化淤泥压缩特性的试验研究

淤泥固化技术在国内已经进入到工程应用阶段，明确固化淤泥的压缩特性对于指导淤泥固化工程的设计具有重要意义。通过单因素试验方案对不同初始含水率、不同水泥添加量、不同养护龄期的固化淤泥的压缩特性进行了研究。结果发现，固化淤泥压缩特性的最大特点是存在固结屈服应力，当荷载小于固结屈服应力时固化淤泥的压缩性非常小，而固化淤泥屈服之后的压缩性是屈服前压缩性的20倍以上，并且远大于未处理淤泥的压缩特性。淤泥本身是高压缩性的土，固化处理以后变为中等压缩性和低压缩性的土体。固化淤泥的固结屈服应力随水泥量增加线性增大，龄期越长、含水率越低固结屈服应力越大。固化淤泥的这种在固结屈服应力处发生突变的压缩特性和天然沉积结构性土类似，可以用双对数压缩模式来表示固化淤泥的这种压缩特性。

Experimental study of compressibility behavior of solidified dredged material

Dredged material(DM) solidification technique was gradually put into engineering application in China,determination of the compressibility behavior cement-treated clays is of great importance to direct DM solidification engineering.Compressibility behaviour of cement solidified dredged material(SDM) was conducted through single factor experiment considering initial water content,cement content and curing time in the oedometer tests.Results show that the significant characteristics for the SDM compressibility is there exist a yield stress,when external load is below the yield stress;the compressibility is very low,however,once the external load exceed the yield stress,the compressibility of the SDM suddenly increases to more than 20 times at the post-yield state than that pre-yield state,and is also larger than that of the untreated dredged material.The untreated dredged material is belong to high compressibility soil according to criterion,and the cement treated dredged material transfers to medium or low compressibility soil.Yield stresses of SDM increase linearly with increased cement content;lower water content and longer curing time get larger yield stresses.The compressibility behaviour of SDM is similar to that of the natural sedimentary soils,double logarithm compression pattern is fitted to depict the sudden drop compressibility behaviour of SDM.