Seismic Behaviour of Beam-Column Joints of Precast and Partial Steel Reinforced Concrete

A beam-column joint of precast and partial steel reinforced concrete( PPSRC) is proposed for precast reinforced concrete frames. The PPSRC consists of partial steel and reinforced concrete. The partial steel is located in the core joint region and the connections between concrete members. This paper presents an experimental study of a series of PPSRC specimens. These specimens are tested under low cyclic loading.Experimental results demonstrate that the bearing capacity of the PPSRC specimens is 3 times that of the ordinary reinforced concrete( RC) beam-column joints. The strength and stiffness degradation rates are slower compared with that of the RC beam-column joints. In addition,the strength of the core joint region and the connections is higher than other parts of the PPSRC specimens. Beam failure occurs firstly for the PPSRC specimens,followed by column failure and connections failure. The failure of the core joint region occurs finally.Test results show that the seismic performance of the PPSRC is better than that of the ordinary RC beam-column joints.

不同轴压比下预制装配式部分钢骨梁柱节点动力性能研究

考虑约束效应、强度退化及应变率效应,运用ABAQUS有限元分析软件,建立了预制装配式部分钢骨钢筋混凝土(PPSRC)梁柱节点力学性能有限元分析模型,通过试验结果验证该模型的有效性,采用验证后的有限元模型,研究了不同轴压比下PPSRC梁柱节点的动态力学性能。研究表明,提出的有限元分析模型可较好地预测PPSRC梁柱节点的力学性能。受应变率效应的影响,动态荷载作用下轴压比对PPSRC梁柱节点的承载力影响不大,PPSRC梁柱边节点的承载力随轴压比的提高无明显变化,轴压比提高后,PPSRC梁柱中节点的屈服承载力和极限承载力略有增大,但较大位移水平下,轴压比高的PPSRC梁柱中节点,其承载力退化更加明显;相同位移水平下,正向加载时的刚度始终大于反向加载时的刚度,轴压比提高后,PPSRC梁柱节点的刚度增大,但较大位移水平下,轴压比高的PPSRC梁柱节点,其刚度退化更加明显;轴压比对PPSRC梁柱节点的延性性能无明显影响;轴压比提高后,PPSRC梁柱节点的耗能能力提高。

预制装配式部分钢骨梁柱节点抗火性能分析

确定材料高温特性、热工参数以及时温曲线后,建立构件抗火性能分析模型,通过试验结果可验证模型的有效性.基于此,建立预制装配式部分钢骨钢筋混凝土(PPSRC)梁柱节点抗火性能分析模型,进行了PPSRC梁柱节点温度场分析以及耐火极限影响因素分析.研究表明,火灾条件下混凝土表面温度高于其内部温度,且随着深度的增加,温度逐渐降低,PPSRC梁柱节点内的部分钢骨升温速度高于其外层混凝土的升温速度;无防火措施时,PPSRC梁柱节点同一截面的温度分布不均,连接区是PPSRC梁柱节点抗火的薄弱区域;连接区喷涂防火涂料后,其平均温度降低明显,阻热效果良好;荷载比增大后,相应位移增大,耐火极限降低,荷载比超过一定限值时,PPSRC梁柱节点的失效位置发生变化.