【摘要】 环形钢筋连接的预制混凝土空心楼板，采用密拼连接方式，实现预制底板间有效传力，避免预制底板外伸钢筋冲突的难题。为研究基于环形钢筋连接的预制混凝土密拼空心楼板的受力性能，共设计4个试件，研究试件的破坏模式、荷载-位移发展规律、承载力、刚度及变形能力。结果表明：预制试件的受力阶段、损伤发展过程和现浇试件的类似，预制试件的开裂荷载、屈服荷载与现浇试件基本接近，刚度比现浇试件稍低，开裂位移和屈服位移比现浇试件略大。加载过程中，预制试件跨中拼缝处的环形钢筋应变逐渐增加，并进入了屈服阶段，起到了连接预制底板的作用，能有效保证试件的承载力和延性。采用钢板焊接连接肋梁底部纵筋的试件，因焊接质量差、纵筋连接过早失效而未充分发挥受拉作用，峰值承载力比现浇试件的低，且达到峰值承载力后，预制试件的承载力快速下降；采用机械套筒连接肋梁底部纵筋的试件，承载力与现浇试件的相当，延性稍差，基本上实现了等同现浇的目标。更多还原

【Abstract】 The precast concrete hollow-core slabs based on loop rebar connections adopt the method of close connection to realize the effective force transmission between precast slabs and avoid the problem of overhanging steel bar conflict of precast slabs. In order to study the mechanical properties of precast concrete hollow-core slabs based on closed loop rebar connections, a total of four test specimens were designed to study the failure mode, load-displacement development law, bearing capacity, stiffness and deformation capacity. The results show that the loading stages and damage development processes of the precast specimens are analogous to those of cast-in-place specimens. The cracking load and yield load of the precast specimens are nearly identical to those of the cast-in-place specimens, although the stiffness is slightly lower. Additionally, the cracking displacement and yield displacement of the precast specimens are marginally larger than those of the cast-in-place specimens. During loading, the strain in the closed loop rebar connections at the mid-span of the precast specimens increases gradually into the yielding stage, effectively connecting the prefabricated bottom plates and ensuring load bearing capacity and ductility. However, due to the poor weld connection quality, the longitudinal reinforcement connections with welding steel plates at the bottom of the rib beams failed prematurely, the precast specimens did not fully utilize their load bearing capacity. Consequently, their peak load bearing capacity is lower than that of the cast-in-place specimens, and upon reaching the peak load bearing capacity, the load bearing capacity of the precast specimens declines rapidly. Specimens with bottom longitudinal reinforcement of the rib beams connected by mechanical sleeves have load bearing capacity comparable to that of cast-in-place specimens, with slightly inferior ductility, essentially achieving equivalent cast-in-place performance.更多还原