Experimental Study of Horizontal Bearing Behavior of Single Piles and Pile Cap with Two Piles

To study the influences of the pile cap on the horizontal bearing behavior of pile foundation,the Liyutuo Bridge over Jinma River in Dujiangyan City was cited as an example and the horizontal static load tests were respectively made for the two nos.of the single piles and the pile cap with two piles.The tests were carried out in an excavated pit,using the slow maintaining loading and unloading method.The horizontal critical loads and horizontal ultimate loads for the single piles and the pile cap with two piles were measured and the displacement deformation values and influential depth of the single piles and the pile shafts under the pile cap changing with the depth were analyzed.The results of the tests demonstrate that the pile cap can significantly improve the horizontal bearing capacity of the pile foundation and increase the capacity of the foundation against the horizontal deformation.As compared to the single piles S1 and S2,the horizontal critical load of the pile cap with two piles is increased by 264%against the pile S1 and 191%against the pile S2 while the horizontal ultimate load is increased by 238% against the pile S1 and 195% against the pile S2.