“排水板+高真空击密法”处理吹填砂及深层软土地基效果分析

Analysing on Effect of “Drainage Plate with High Vacuum Densification Method” in Treating Hydraulic Fill Sand and Deep Soft Foundation

通过浅层平板载荷试验、标准贯入试验、双桥静力触探试验、十字板剪切试验和室内土工试验等多种手段,对采用"排水板+高真空击密法"的某工程场地吹填砂和深层软土地基处理效果进行分析,结果表明该软基处理效果明显,土体强度得到显著提高;对双桥静力触探试验和标准贯入试验液化判别结果的对比研究表明双桥静力触探试验液化判别更偏于安全,且锥尖阻力基准值取值越高,越安全;根据双桥静力触探参数和十字板剪切参数的关联性,对比了不排水抗剪强度推算值和十字板剪切试验实测值,对实际工程应用中的不排水抗剪强度推算取值提出了建议。

The treatment effects of the hydraulic fill sand and deep soft foundation in a project by the＂drainage plate with high vacuum densification method＂is analysed by various means,such as shallow plate loading test,standard penetration test,double-bridge static cone penetration test,vane shear test and laboratory soil test. The results show that the treatment effect of the soft foundation is obvious and the soil strength is improved significantly. The comparative study on the liquefaction of double bridge static cone penetration test and standard penetration test shows that the identification of the double-bridge static cone penetration test is safer than that of the standard penetration test,and the higher reference value of the cone tip resistance,it is safer. The extrapolated values of undrained shear strength and measured values of vane shear tests are compared with the correlation between the double-bridge static cone penetration parameter and the vane shear parameter. Some suggestions are proposed for the calculation of undrained shear strength in practical engineering applications.