STUDY OF CALCULATION MODEL OF REINFORCED CONCRETE BEAM-COLUMN JOINT CORE

Stress of beam-column joint is complex， and modified compression field theory and the diagonal compression strut model have some shortages． Based on predecessors’study on the diagonal compression strut mechanism and softened strut-and-tie mechanism，a new calculation model of shear capacity of beam-column joint core was proposed，where the horizontal shear carried by both the diagonal compression strut mechanism and softened strut-and-tie mechanism was combined by a certain percentage． According to the proposed model，the shear capacity of beam-column joint core was calculated，concrete compressive strength and horizontal stirrup ratio were also computed． Experimental value of largest shear stress of 82 specimens at home and abroad was compared with calculated value using the method，and the mean ratio of experimental value to calculated value by the method was 1. 154 with coefficient of variation of 0. 131． The discreteness of experimental value to calculated value by the method was smaller than that of experimental value to calculated value by softened strut and tie model，and the feasibility of the method was verified．