Model tests on bored piles under vertical load on different pile-tip soils

The primary goal of this research is to study the influences of different pile-tip soils on the bearing characters of bored piles. Soils laid around and under piles are selected based on characteristics of strata passed through by bore piles in soft soil. Prefabricated model piles are pre-installed onto the pile-tip soils with film around them to remove influences induced by differences in coarse degree and diameter of piles, and to produce unloading effect on piles. Test data are gained after static loading tests on six model piles, and the influences on side resistance are discussed. Relations between side resistance and relative displacement are established and normalized to quantitatively solve the problem. It is concluded that the model tests on the influences of different pile-tip soils on the bearing characters of bored piles are valid, and more test data and project practice are needed to solve this problem thoroughly.