Abstract: This paper presents the vertical displacement measurement errors from static axial pile loading tests and plate load tests on soils. The results indicate that, the possible sources of the vertical displacement measurement errors are errors from the measurement equipment, improper equipment installation and disturbance from the adjacent environment. These factors lead to various errors in the vertical displacement measurement, and the errors appear to be inaccurate and unreasonable to the justify the test results. The factors causing the vertical displacement measurement errors are analyzed in detail, and the method of displacement correction is also provided to judge the conclusion from the corrected data. Suggestions for minimizing or eliminating various errors in the static load test on piles and on soils are also provided in the paper.

Key words: Static Load Tests, Influencing Factors, Vertical Displacement, Testing Data Collection, Error Analysis, Fault Errors, Displacement Corrections