TESTS ON INCLINED COLUMN SPREAD FOUNDATION WITH INNER CIRCULAR STEEL TUBE SUBJECTED TO UPLIF AND HORIZONTAL CONBINATION LOADS

Based on four in-situ tests on inclined column foundations with inner circular steel tube subjected to uplift and horizontal combination loads, the bearing capacity and failure mechanism of foundations with different arrangements of anchorage and longitudinal reinforcing steel bars are analysised. The results show that the load-displacement curves have obvious elastic, yielding and destructive stages. Under uplift and horizontal combination loads, a higher ratio of reinforcement of the column could increase the bearing capacity of the foundation column. The inclined column foundations losed their bearing capacity when the concret above the shear-compression zone of the bottom anchorage reached the strength limit or when the subgrade soil failured. The anchorage improved the coordinated performances of circular steel tube, and longitudinal bars and foundation slab. Therefore, the anchorage makes full utilization of mechanical property of all structural components of the foundation, which makes the mechanical condition of foundation much more proper.