Abstract: In MU US desert, full-scale in-site tests on the bearing capacity of eccentric grillage foundations subjected to the uplift and uplift combined with horizontal loading were carried out respectively. The load-displacement both of foundation top plane and ground surface, and the soil pressure acted on the footing slab were measured. The uplift mechanism of foundation was analyzed. The results show that under the uplift, uplift combined with horizontal loadings, the load-displacement of the eccentric grillage foundation presented two-staged behavior. Under uplift load only, the ultimate uplift resistance is assumed to be the sum of the dead weight of foundation and the soil mass contained above the bottom of the assembled slab base. The movement resulted by the eccentricity reduced the uplift bearing capacity of foundation. However, under uplift combined with horizontal loading, the ultimate uplift load increased 8.7 percent by comparison to the uplift load case. It indicate that the eccentric foundation structure is more suitable to the load case of uplift combined with horizontal loading in engineering. The angle δ , the consultant to the line from centroid of slab to top plane , is suggested to reflect the eccentricity and applied loads. According to the test results, the pullout capacity decrease rapidly with the increasing of angle δ.

Key words: eccentric grillage foundation, aeolian sand, uplift combined with horizontal loading, breakout factor