INTERPRETATION OF PLATE LOAD TESTS ON RESIDUAL SOIL SITE

This paper addresses problems of interpreting the results of loading t ests in a residual homogeneous, cohesive-frictional soil. Data are pre sented comparing load-settlement behavior measured from tests carried out using circular steel plates ranging from 0.30 to 0.60 m diameter a nd square concrete footings ranging in size from 0.40 to 1.00 m. This paper stresses the need to express test results in terms of dimensionl ess variables in a plot of normalized applied pressure versus settleme nt-to-diameter ratio. In this space, the effect of the size of the loa ded area on measured settlement and on bearing capacity is shown to be negligible for this residual soil site. This approach implies that a unique relationship between normalized pressure and settlement-to-diam eter ratio is observed for both small and large vertical displacements . Interpretation of load tests is made within the context of elastic- and elastoplastic theories. For ultimate bearing capacity, reduced str ength parameters are used to provide a realistic estimation of ultimat e loads. Finally, a numerical approach is proposed for predicting the complete load-settlement behavior of shallow foundations on cemented s oil deposits.