Based on the theory of solving over-determined equations with the least square method and parameters back analysis methods,this paper discusses the approach to quickly determine the compressive moduli of multi-layered soft ground. The approach contains CPTU tests data together with corresponding ground settlement data. It is aimed to establish the empirical relationship formula between compressive modulus and cone tip resistance according to kinds of soils. Finally,the CPTU tests results of soft ground in Chong-qi Bridge are present. The results of the compressive modulus are compared with data of laboratory oedometer tests and other situ tests. Comparisons of the results indicate that the compressive modulus determined with CPTU tests are twice as much as that measured in the laboratory consolidation tests and are in good agreement with that from CPT and SPT. When the compressive modulus from CPTU tests were used directly for design,it would be better in practice.%基于最小二乘法求解超定方程组原理,通过参数反分析,探讨了多层地基条件下,结合地基沉降资料,利用CPTU原位测试技术快速确定地基土压缩模量的方法研究,以求按照土层获得不同的压缩模量与锥尖阻力的经验系数.并结合崇启大桥北接线工程的CPTU试验进行了实例计算.结果表明:CPTU计算压缩模量是室内试验的2倍,与其他原位试验结果相近.若采用该方法为实际工程提供设计压缩模量值效果会更好.
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