The force analysis of reinforced concrete flexural members are usually focused on the limit state that the strain at the edge of the compressive zone of concrete reaches its ultimate compressive strain. However, it is necessary to analyze and calculate the force and deformation under non-limit state in many case. In this paper, the flexural and deformation properties of reinforced concrete beam under non-limit state were studied. Firstly, a program was compiled to analyze the stress distribution in the compression zone of concrete under non-ultimate state, and the stress graph was equivalent to a rectangular stress graph. The numerical results of the stress equivalent coefficient and the height equivalent coefficient of the compression zone were obtained, and the variation curve of the equivalent coefficient was drawn. Secondly, the practical calculation formulas were proposed to calculate the equivalent coefficient of the compression concrete zone under non-limit state by curve fitting. Then, the calculation method of reinforced concrete flexural beams under non-limit state was analyzed by the equivalent coefficient formulas. Finally,a calculation example of flexural bearing capacity of reinforced concrete beams under non-limit state was given.
Crack formation and crack propagation into the compression zone on reinforced concrete beam structures
