Detection of initial strain of main ribs of concrete beam (or slab) by bending moment increment method

Abstract

In the inspection and identification of engineering structures, it is often necessary to understand the force state of the main ribs of the components. Based on the structural performance test, the relationship between the bending moment of the concrete beam (or slab) in the elastic phase and the plastic phase and the strain of the main rib is analyzed. The initial moment of the main beam of the concrete beam (or slab) is proposed by the bending moment increment method. By adding a small amount of bending moment and measuring the strain increment of the main rib, the initial strain of the main rib of the flexural member is estimated to better understand the structural performance of the member. During the bending moment increment detection process, the increase in bending moment is small and does not adversely affect the concrete structure.