Abstract: For optimized pile foundation design, the concepts of cement-flyash-gravel pile (CFGP) and rammed cement-soil pile (RCSP) were combined in this study to form the rammed cement-soil loop pile with CFG cores (CFGCP-RCSLP). The static and dynamic characteristics of the CFGCP-RCSLP composite foundation were studied using in-situ tests. Test results show that with identical soil properties, pile length and pile spacing, the load-settlement curve of the CFGCP-RCSLP composite foundation demonstrates a clear linear relationship. The bearing capacity of the CFGCP-RCSLP composite foundation is 19.1% lower than the CFGP composite foundation, 23.8% lower than that of the RCSP pile composite foundation, and 102% higher than a natural foundation. The blasting tests show that under same explosion energy and the arrangement of blast points, the dynamic characteristics of composite foundations are primarily related to soil properties, pile rigidity distribution and pilling load. The blast point location arrangement directly influences the distribution of peak acceleration along the pile body of CFGCP-RCSLP composite foundations, and the peak acceleration decreases significantly as the pilling load increases.