Experimental study of correlation of dynamic compaction for foundation backfilled with crushed stone

The testing and evaluation about the quality of dynamic compaction is a very important part during high embankment foundation improvement. Based on the theory and practice, the correlation of the test results between Rayleigh wave test(RWT), dynamic penetration test(DPT) and pile static load test(PLT) were studied according to the 1 000 kV ultra-high voltage(UHV) substation. Showing that the results of RWT and DPT can verify the results of PLT, and the first two can be used as indirect means for dynamic compaction detection, which may be appropriate to reduce the assignments of PLT which costs so much and lasts so longer. According to the test results, the mathematical expression of the test results are fitted. Based on the results, the relationship of V-s and fk can be expressed by power function, and the relationship between V-s and E-0 and N-120 can be expressed by exponential function. And the effective reinforcement depth of dynamic compaction and other soil mechanical parameters are inferred. Based on the measured value of the effective reinforcement depth of dynamic compaction, the correction coefficient from 0.24 to 0.27 were putted forward according to Menard formula. The research results will provide certain reference value for the similar projects.