DefinePK

Abstract

A spread footing is sometimes selected for a shallow foundation design on clay layers. Its ultimate bearing capacity usually fluctuates with seasonal changes. Thus, a series of laboratory bearing tests was performed on compacted kaolin specimens with different values of matric suction, which relates to water content. The values of matric suction within the specimens were measured using the contact filter paper technique. All tests were performed after measurement of matric suction by penetrating the rod on the specimen surface until failure. The test results on the normal scale plot show an increase in ultimate bearing capacity with increasing matric suction for all ranges of suction. The increase rate is high at low suction range and decreases with increasing suction. In the semi-log scale plot, the curve of results can be divided into two parts at the point corresponding to the point separating saturated from unsaturated state.