【摘要】 提出了一种腹板摩擦式自定心预应力混凝土框架梁柱节点形式,并通过14个低周反复加载试验,对节点在循环荷载下的力学行为以及耗能特性进行研究,分析钢绞线预应力、螺杆预应力、梁端钢套、螺旋箍筋等参数对于节点性能的影响。试验结果表明,腹板摩擦式自定心预应力混凝土框架梁柱节点具有震后自动复位、主体结构基本无损、耗能机制明确等优点。梁端的钢套避免了混凝土梁柱在相对转动时的局部受压破坏,而位于梁端腹板的摩擦装置则提供了良好的耗能能力。随着初始预应力的加大,节点的初始刚度、临界张开弯矩加大并具有更强的自定心能力;节点的耗能效果主要受摩擦力的大小控制,预应力螺杆的正应力越大,耗能效果越明显。为保证槽钢的传力和摩擦耗能效果,须加强柱预埋钢板在框架柱中的锚固。更多还原

【Abstract】 A beam-column connection of self-centering prestressed concrete(SCPC) frame with web friction devices is proposed.Mechanical behavior and the energy dissipation(ED) mechanism are investigated through fourteen low cyclic tests.The influence of parameters(initial tendon forces,initial bolt forces,steel jacket at the beam end and spiral hoops,etc.) on the performances of the connections are analyzed.Test results show that the SCPC connection has a good self-centering capacity and an explicit ED mechanism,and that the beams and columns can be damage-free after earthquake.The steel jacket at the beam ends avoids local crushing of the concrete as the beam rotates against the column.The friction device at the beam web provides the ED capacity.As the initial prestressing forces increase,higher initial stiffness,imminent gap-opening moment and larger self-centering capacity are obtained.The ED capacity is mainly controlled by the friction forces.The larger the normal forces of the friction bolts are,the better the ED effect is.To ensure the transfer of friction loads from channels and the energy dissipation,the anchorage of the embedded steel plates in the column needs to be enhanced.更多还原