钢框架梁端翼缘板式加强型节点力学性能试验研究

EXPERIMENTAL STUDY ON MECHANICS PROPERTY OF FLANGE PLATE-REINFORCED CONNECTIONS OF STEEL FRAMES

钢框架梁端翼缘板式加强型节点是梁柱改良抗震节点的一种形式,这种节点包括翼缘板加强型及盖板加强型节点两种类型。为了研究这两种连接形式的延性及抗震性能,设计制作了4个缩尺比例为1/2的梁柱T型试件,研究了节点试件在循环荷载作用下的破坏形态、滞回曲线、骨架曲线、极限荷载、最大塑性转角、延性性能等,作为比较,还进行了1个传统栓焊节点试件的试验。试验结果表明,梁端翼缘板式加强型节点可以耗散大部分能量,避免梁根部应力发展导致梁柱连接焊缝过早出现脆性破坏,实现塑性铰外移。与传统节点相比,具有更强的塑性变形能力和耗能能力,是一种较为理想的延性节点。研究结果还表明,采用翼缘板或盖板对梁翼缘进行加强可以使试件承载能力有所提高,在抗震设计中可以考虑翼缘加强板对试件承载能力提高的影响。此外,该文还给出了翼缘板及盖板加强节点的设计步骤,为此类型节点的工程设计提供参考。

The plate reinforced connection is a type of improved beam-column anti-seismic connections,which includes a flange-plate reinforced connection and a cover-plate reinforced connection.In order to study the ductility and aseismic performance of this connection forms,four beam-column T-joints of a steel moment-resisting frame were designed at 1/2 scale.There were two flange-plate reinforced connection specimens and two cover-plate reinforced connection specimens.The failure modes,the hysteresis curve,the curve skeleton,the ultimate load,the maximum plastic rotation,and the ductility performance under a cyclic loading were studied.As compared,one ordinary connection specimen was tested.The results indicate that there is an expanded plastic hinge zone which was formed at the outside of the flange-plate by setting a flange reinforced plate to a beam-end reinforced connection,which could consume the most energy and avoid premature brittle failure at the weld between the beam and column due to the development of the beam-end stress.Compared with the traditional connections,the plastic deformation capacity and energy capacity of the reinforced connection are better,thusly this connection is an ideal ductile node.The results also showed that the bearing capacity of the specimens could be improved,consequently the bearing capacity improvement of the specimens should be considered in aseismic design.Moreover,the design steps of the connections have been given,which offered references for the corresponding engineering design of the connections.