Experimental Analysis On Seismic Resistant Behavior Of R.C.Beam－+ Shaped Column Staggered Joint

During recent years, R.C.Beam-special shaped column structure with staggered joint comes into being, with the wide use of special-column-shear wall structure and staggered structure. special shaped column structure with staggered joint, the calculation method of which is necessary to resolve, is wick in the staggered special-column frame structure. According to my materials, these kind of research is almost blank. On the basis of experimental study and analysis on R.C.beam-special shaped column joints and staggered joints with rectangular column, an experimental research on 4 R.C.beam-special shaped(+) column staggered joints under low axial compression ratio(0.05) is achieved. This paper does researches and investigations on the influences of staggered height, shear-compression ratio and flange on the seismic resistant behaviors of the staggered joints under low cyclic loading. This paper also does a research on the agreement of the 'ductile joint'and the calculation formulas for shear strength for R.C.beam-special shaped column joints of Tianjin technical Specification for Lightweight Framed Structures with Special-shaped R.C. Columns of Large Bay Dwelling Houses(DB 29-16-98),a number of design suggestions related to the calculation of shear strength of R.C.beam-special shaped column staggered joints are proposed as well. After the test and analysis on R.C.beam-special shaped(+) column staggered joints, the conclusion are drawn as following: 1,because the bank performance of the longitudinal bars in the joint area of the special-column staggered joint in the beam-column complex body is better than that of the normal mid-level joint and that of the rectangle-column staggered joint, the power-wasting performance of the special-column staggered is better than that of the normal mid-level joint and that of the rectangle staggered joint. 2, The main reason of the damage of the special-column is the strong shear force ratio, so it's important to control the shear force ratio of the joint. 3,The joint calculated by the formulation in the "Tianjin technical specification for light weight framed dwelling houses"(DB29-16-98) performances well when the shear-force ratio is small. When the shear-force ratio of the joint is small, the expression for the joint of Tianjin Code can satisfy the demand for the ductility of the joint. 4,For the second and third kind of joint which height is longer than the beam height, the mechanics performance approach the mid-level joint, the calculation shear is the bigger one in the joint area, and the calculation height is the height of the corresponding beam; for the first kind of joint which shear-force ratio is high, the calculation height of the joint is the whole height of the joint, for the calculation of the bearing strength ,but the calculation shear is the shear in the mid of the joint and augmentation should be considered for the ductility. 5,The flank can limit the development of the crack. When there is oblique pressure-damage, there is no obvious function of the flank to the joint.