Flexural Performance of Mortise-tenon Prestressed Bolt Joints in Prefabricated Station Structure

Abstract

Objective The rationality of joint structures is crucial for station safety. Therefore, it is necessary to study the enhancement effect of additional prestressing measures on the flexural performance of prefabricated station structure bolt joints. Method A refined finite element model of mortise-tenon prestressed joints using prestressed bolts is established. Through four-point bending loading, the influence of different bolt design parameters on the flexural bearing capacity of joints is analyzed. Result & Conclusion During the bending moment loading process, joints connected by prestressed bolts exhibit good overall integrity. Stress concentration on the handhole position on the concave-side component tension side leads to tensile failure of nearby concrete. The vertical displacement and joint-seam opening of prestressed bolt joints gradually decrease with increasing bolt diameter and length, and the reduction amplitude decreases as the bolt diameter and length increase. Setting bolt preload force can significantly improve the flexural capacity of the joints, with a noticeable effect on controlling the deformation of joint-seam opening. Recommendations to optimize design parameters for prestressed bolt diameter, length and preload force are proposed.

Keywords

• metro
• station
• prefabricated structure
• prestressed bolt joint