空腹式型钢混凝土异形柱中框架抗侧刚度试验研究

通过对1榀1/2。5比例两跨三层的空腹式型钢混凝土(SRC)异形柱中框架在反复荷载作用下的试验研究，分析了结构的弹塑性特征以及整体和层间抗侧刚度的退化过程。通过分析可知:空腹式SRC异形柱框架沿竖向的刚度分布较均匀；层刚度与整体刚度的退化均表现出由快到慢的规律；获得了层间位移角的变化与层刚度退化之间的关系；结构正、负向弹塑性性能接近，极限层间位移角大于规范规定的限值，抗倒塌能力强；空腹式型钢混凝土异形柱中框架的延性优于钢筋混凝土异形柱框架；结构破坏时可以形成梁铰机制，符合“强柱弱梁”的要求。

EXPERIMENTAL STUDY ON LATERAL STIFFNESS OF LATTICE STEEL REINFORCED CONCRETE MIDDLE FRAME WITH SPECIAL-SHAPED COLUMNS

According to the experimental study on a 1/2.5-scaled model of two-span and three-story middle frame composed of reinforced concrete beams and lattice steel reinforced concrete (SRC) special-shaped columns under reversed loading,the elasto-plastic feature,integral and inter-story lateral stiffness degradation of the structure were analyzed. The test results indicate that the lattice steel reinforced concrete middle frame has uniform vertical stiffness,the degradation of which shows a fast to slow regulation. The relationship between story drift and the ratio of story stiffness degradation was obtained. The elasto-plastic behavior of the structure in positive and negative directions is similar. The ultimate elasto-plastic story drift rotation is larger than the limit value specified by the code,indicating the high capacity of collapse resistance. Compared with the reinforced concrete frame with special-shaped columns,the ductility of lattice SRC frame structure is better. The failure mechanism of the structure is the beam-hinged mechanism,satisfying the seismic design principle of “Strong Column and Weak Beam”.