Bearing Capacity of Closed and Open Ended Pipe Piles in Clayey Soil

Abstract

This paper investigates the impact of close and open ended condition on the capacity of pipe piles installed in medium clayey soil using pressed or jacked and hammered techniques and tested under the effect of vertical static compression load. 36 experimental model steel pipe piles (18 models for each open and closed ended) introduced and analyzed to clarify the influence of soil plug formation on the behavior of pipe piles.Different parameters are studied such as pile diameters (2.5, 3.5 and 4.1) cm, piles lengths (30, 40 and 50) cm and type of installation methods (pressed and hammered(. Results of the test program indicated that the ultimate load capacity of open-ended pipe piles tended to increase as the pile diameter and length increase for both pressed and hammered. The plugging of open piles does not contribute significantly on the capacity of pile in clay. For all model pile tests the load capacity of the closed ended piles is (5 – 30) % greater than that of the open ended for both type of installation (pressed and hammered) under the same geometric conditions.