ANALYSIS ON SHEAR CAPACITY OF SRC DEEP BEAMS BASED ON MODIFIED STRUT-AND-TIE MODEL

Based on the research of steel reinforced concrete (SRC) deep beam test and the modified strut-and-tie model (STM), a modified strut-and-tie model for SRC deep beams was established and the shear capacity design formula of SRC deep beams based on the model was deduced, which considers the favorable influences of the tie bar, taking the depth of compression zone of SRC deep beams as the depth of the top nodes and reasonably simplifying the steel flange and web. By comparing the test results and the calculation in this paper with the strut-and-tie models of ACI and Chinese code, the following conclusions can be drawn:1) force-transferring mechanism and failure mode can be reflected effectively, and the calculated values of shear capacity based on the modified strut-and-tie model for SRC deep beams presented in this paper agrees with the test result; 2) the shear capacity of SRC deep beams calculated by the JGJ 138-2001 shows high discreteness and low average value. The shear capacity of SRC deep beams with shear span ratios greater than 2 calculated by the YB 9082-2006 was not conservative.