预埋型钢的钢筋混凝土柱-钢梁组合节点抗震性能试验研究及设计方法

Experimental study on seismic behavior and design method of reinforced concrete column-steel beam composite joints with embedded profile steel

为了提高钢筋混凝土柱-钢梁(RCS)组合节点的传力效率和抗震性能,提出一种带预埋型钢的RCS组合节点。设计并制作了4个试件,通过拟静力试验,研究预埋型钢的延伸长度和配钢率对试件破坏模式和抗震性能的影响,并提出该节点的设计方法。研究结果表明:节点的破坏模式分为混凝土柱型钢截断处破坏、混凝土柱端破坏、型钢截断处和混凝土柱端同时破坏(界限破坏),其中混凝土柱端破坏的节点具有更高的承载力和耗能能力;当预埋型钢的延伸长度超过界限长度时,节点发生混凝土柱端破坏,可实现预埋型钢有效传力的作用;预埋型钢配钢率的增大可提高混凝土柱端破坏节点的抗震性能,但相应的延伸长度也随之增大;型钢截断处混凝土柱受弯承载力为普通钢筋混凝土柱的68%,混凝土柱端受弯承载力为型钢混凝土柱的86%。最后,提出了预埋型钢合理延伸长度的设计方法,并给出了延伸长度系数、预埋型钢配钢率及节点的设计建议。

To improve the force transmission efficiency and seismic performance of reinforced concrete column-steel beam(RCS)composite joint,a kind of RCS composite joint with embedded profile steel was proposed.Four specimens were designed and manufactured.Through the pseudo static test,the influence of the extension length and steel ratio of embedded profile steel on the failure mode and seismic performance of the specimen was studied,and the design method of the joint was proposed.The results show that the failure modes of the specimens can be classified into failure of the concrete column at the profile steel cutoff,concrete column end failure,and simultaneous failure at the profile steel cutoff and the concrete column end(boundary failure).Among them,the specimens with concrete column end failure have higher bearing capacity and energy dissipation capacity.When the extension length of the embedded profile steel exceeds the boundary length,the specimen undergoes concrete column end failure,which can realize the effective force transmission of embedded profile steel.The increase of the steel ratio of the embedded profile steel can improve the seismic capacity of concrete column end failure specimens,but the extension length of the embedded profile steel should also be increased.The flexural bearing capacity of the concrete column at the embedded profile stel cutoff is 68%of that of the ordinary reinforced concrete column,and the flexural bearing capacity of the concrete column end is 86%of that of the steel reinforced concrete column.Finally,the design method of the reasonable extension length of the embedded profile steel was proposed,and the design suggestions for extension length coefficient,steel ratio of embedded profile steel and joint were given.