Study on Calculation Method of Internal Force of Integral Abutment-Pile-Soil Interaction

Abstract

Integral abutment jointless bridge (iajb) has the advantages of long service life, convenient construction and low construction and maintenance cost. At present, it has been widely used at home and abroad. Based on an actual iajb, an experimental model of integral abutment pile structure is designed and made. The quasi-static test is carried out under low cyclic displacement load, and the interaction between integral abutment, H-steel pile and soil is studied, with emphasis on the strain and bending moment of abutment and pile foundation. The test results show that the strain distribution of pile body is “Cup” shape when the abutment moves forward and “olive” shape when the abutment moves negatively. The maximum compressive stress and tensile stress under positive displacement load are greater than those under negative displacement load. Therefore, when the temperature increases, the internal force of pile foundation is greater than that when the temperature decreases, which means that H-shaped steel foundation pile is more unfavorable when the temperature increases in summer. In order to reduce the adverse effect of temperature on foundation piles, it is suggested that the overall closure temperature of the bridge should be slightly higher than the annual average temperature. In addition, the calculation also shows that when negative load is adopted, the pile bending moment calculated by these methods is not different from the test results, and the distribution law is similar to that of traditional foundation piles. However, under normal load, the pile bending moment calculated by classical theory or bridge code is quite different from the test results, and the distribution law is also different. In this paper, the moment of integral abutment pile-soil interaction is calculated accurately by polynomial fitting method and huanglin method, which can be used in practical engineering and provide reference for the design and application of iajbs.