Wave equation analyses of full-scale test piles using measured field data

"Research study number 2-5-67-125: Bearing capacity for axially loaded piles. Sponsored by the Texas Highway Department in co-operation with the U.S. Department of Transportation Federal Highway Administration."A procedure for obtaining soil damping constants for use in wave equation analyses using full-scale test piles and measured field data was developed in this study. The validity of the procedure was shown through correlation of measured dynamic and static field data with results obtained from wave equation analyses using three full-scale instrumented test piles. Two of the piles were embedded in clay and the third in saturated sand. Results of this study indicate the feasibility of determining soil damping constants using the one-dimensional wave equation to analyze field driving and load test data. Although results showed soil damping constants based on soil type for pile bearing predictions was verified. The increase in bearing capacity resulting from soil "set-up" was shown to be predictable from the increased dynamic driving resistance during driving were shown to be valid at redriving. Records of 37 additional full-scale load test piles were analyzed using wave equation analyses to determine soil damping constants for other type solid. Predicted bearing capacities were compared with load test results adjusted for soil set-up in clays. The results were encouraging in light of the multiple load test procedures employed and the problem of evaluating soil set-up in clays for piles which were load tested from the 5 to 78 days after initial driving