废弃纤维再生混凝土框架中柱节点抗震性能试验研究

Experimental study on the seismic behaviors of wasted fiber recycled concrete frame joints

完成了再生骨料取代率为50%,废弃纤维长度分别为12 mm、19 mm、30 mm以及废弃纤维体积掺量分别为0.08%、0.12%、0.16%的5个废弃纤维再生混凝土框架中柱节点在低周反复荷载作用下的抗震性能试验研究。主要对不同废弃纤维长度、不同废弃纤维体积掺量下梁柱节点的破坏形态、滞回特性、延性性能、耗能特性等问题进行了对比分析。结果表明:废弃纤维再生混凝土框架节点的破坏均经历了初裂、通裂、极限、破坏四个特征阶段,当纤维长度为19mm,废弃纤维体积掺量为0.12%时,废弃纤维再生混凝土梁柱节点构件的滞回性能、延性性能及耗能性能较好;废弃纤维的体积掺量比废弃纤维长度对梁柱节点抗震性能的影响大。提出了废弃纺织纤维再生混凝土的抗剪承载力计算公式,计算结果与试验结果吻合较好。

The seismic behaviors of interior frame joints composed of wasted fiber recycled aggregate concrete were studied experimentally. The effects of certain design parameters such as the length and volume ratio of wasted fiber with a constant replacement rate of recycled aggregate on the anti-seismic performance of the frame were investigated, 5 full-scale specimens were designed and fabricated, then cyclic loading tests were conducted. In the tests, the replacement rate of recycled aggregate was kept at 50%, the wasted fiber length was 12 mm, 19 mm, 30 mm and volume content was 0.08%, 0.12% and 0.16% respectively. The failure mode, hysteretic property, ductility, energy dissipation characteristics and other issues of frame joints were analyzed with different wasted fiber lengths and volume contents. The experimental results show that the destruction of wasted fiber recycled concrete frame joints experience four stages, they are initial cracking, thorough cracking, ultimate stage and failure stage. With the fiber length of 19 mm and volume content of 0.12%, the wasted fiber recycled concrete beam-column joint has better seismic behaviors. Compared with the wasted fiber length, the volume of wasted fiber content has greater influence on the seismic performance of beam-column joints. A shear strength calculation formula for wasted fiber recycled aggregate concrete was put forward. The calculation results coincide well with the test results. © 2017, Editorial Office of Journal of Vibration and Shock. All right reserved.