Experimental and Application Study on Underpinning Engineering of Bridge Pile Foundation

In order to study the theory and application of the pile foundation underpinning technology, 3 local node models of underpinning structures with a similarity ratio of 1/1 were made and the progressive repeated static loading tests were conducted. The shear and antislip properties of the joint are studied, and the improved formula for calculating the shear capacity is proposed. The results show that a planting bar plays a major role in shear resistance, and the hoop rate can improve the shear capacity of the interface. The new formula for calculating the shear-bearing capacity is proposed, and the calculation results of the formula of shear-bearing capacity are in good agreement with the experiment results. It is completely feasible to use this formula to calculate the shear-bearing capacity of the pile foundation underpinning structure. During the test, the bearing capacity of the model is good, which proves the reliability of the underpinning technology is good, and it can provide experimental and theoretical basis for the underpinning of similar projects.