钢板-纤维增强混凝土组合双连梁抗震性能试验研究

为改善小跨高比钢筋混凝土连梁的抗震性能，考虑基体材料与钢板的影响。本文提出新型钢板-纤维增强混凝土组合双连梁，并对普通混凝土双连梁、内置钢板-混凝土组合双连梁和钢板-纤维增强混凝土组合双连梁试件进行了低周反复加载试验，对双连梁的破坏过程、破坏形态、承载能力、变形能力和耗能能力等进行研究。结果表明：除了普通混凝土双连梁试件发生剪切破坏之外，内置钢板-混凝土组合双连梁试件发生弯剪破坏，钢板-纤维增强混凝土组合双连梁试件发生延性较好的弯曲破坏；加入钢板后的钢板-组合双连梁试件在峰值点处的承载力相对普通混凝土双连梁提高将近1.56倍，与钢板-纤维增强混凝土试件峰值点处承载力相差不大，表明钢板的内置可以改善双连梁开缝引起的内力损伤，纤维的加入对组合双连梁承载力提高影响不大。在破坏点处，钢板-纤维增强混凝土组合双连梁试件的累积耗能分别是普通混凝土双连梁、内置钢板-混凝土组合双连梁试件的5.26和2.2倍，表现出较好的承载能力、变形能力和耗能能力。直到试件到达最终破坏时，钢板-纤维增强混凝土组合双连梁表面混凝土仍然保持完整，从而可以达到减小甚至避免了混凝土开裂破坏，减少震后修复费用，为组合双连梁的实际应用提供一定的理论基础。

Seismic Behavior of Plate-Fiber Reinforced Concrete Composite Double Coupling Beams

In order to improve the seismic behavior of the reinforced concrete coupling beam with small span-to-depth ratio, the influence of matrix material and steel plate is considered. A new type of plate-fiber reinforced concrete composite double (PFRCCD) coupling beam is proposed in this paper. The failure process, failure modes, bearing capacity, deformation capacity and energy dissipation of the ordinary concrete double (OCD) coupling beam specimen, plate-reinforced composite double (PRCD) coupling beam specimen and PFRCCD coupling beam specimen were studied. The results show that, the shear failure occurred in the OCD coupling beam specimen, the bending shear failure occurred in the PRCD coupling beam specimen, and the good ductility and bending failure occurred in the PFRCCD coupling beam specimen. After adding steel plate, the bearing capacity of the PRCD coupling beam specimen at the peak point is nearly 1.56 times higher than that of the OCD coupling beam specimen. The bearing capacity of the PRCD coupling beam specimen differs little from that of the PFRCCD coupling beam specimen at peak point. The results show that the steel plate can improve the internal force damage caused by the opening of the double beam, and the addition of fiber has little influence on the increase of the bearing capacity of the composite double coupling beam. At the failure point, the cumulative energy dissipation of the PFRCCD coupling beam specimen is 5.26 and 2.2 times that of the OCD coupling beam specimen and the PRCD coupling beam specimen, respectively. Compared with the other two specimens, the PFRCCD coupling beam specimen exhibits better bearing capacity, deformation capacity and energy dissipation capacity. Until the final failure of specimen, the concrete of the PFRCCD coupling beam specimen still remains intact, so as to reduce or even avoid concrete cracking damage and reduce post-earthquake repair costs. It provides a theoretical basis for the practical application of composite double coupling beam.