基于扁铲侧胀试验的绍兴软土不排水抗剪强度研究

Study on Undrained Shear Strength of Shaoxing Soft Soil Based on Flat Dilatometer Test

扁铲侧胀试验是国内外岩土工程勘察领域广泛使用的原位测试技术,常用于评价软土的不排水抗剪强度。通过总结国内外利用扁铲侧胀试验评价土体不排水抗剪强度的经验计算公式,基于绍兴地区扁铲侧胀试验及原位十字板试验结果,分析了典型经验公式评价绍兴软土不排水抗剪强度的适用性,并提出了修正计算方法。结果表明,现有的典型经验公式均会导致软土不排水抗剪强度的计算结果偏大。基于Skempton公式的修正经验计算方法考虑了绍兴地区土性差异的影响,计算结果与实测结果较为接近,可以适用于绍兴软土(ID<1.2)的不排水抗剪强度评价。

Flat dilatometer test(DMT)is an in-situ test widely used in geotechnical engineering investigation at home and abroad,and the DMT is often used to evaluate undrained shear strength of soft soil.Based on the empirical formulas for evaluating undrained shear strength of soft soil by DMT,and combined with in-situ test results of DMT and field vane test(FVT)in Shaoxing area,the applicability of typical empirical formula and modified calculation method for evaluating undrained shear strength of soft soil in Shaoxing are analyzed.The results show that(1)the existing typical empirical formulas lead to larger calculation results of undrained shear strength of soft soil;(2)the modified empirical calculation method based on Skempton formula takes into account the influence of soil properties difference in Shaoxing area,and the calculation results are close to the FVT measured results,which can be applied to the undrained shear strength evaluation of Shaoxing soft soil(ID<1.2).