外伸式端板连接钢-混凝土组合节点裂缝发展规律及破坏模式

Developing rules and destroying patterns of steel-concrete composite joints crack with extended end-plate connections

为研究外伸式端板连接型钢梁-混凝土柱组合节点的受力性能,对7个外伸式端板连接复合焊接环式箍筋混凝土柱-蜂窝钢梁组合节点试件进行了低周反复荷载作用下的拟静力试验.结果表明,外伸式端板连接型钢梁-混凝土柱组合节点裂缝出现时荷载较小;在构件屈服后,在节点区出现主X型交叉斜向剪切裂缝,破坏阶段,节点核心区成通裂状态,部分混凝土压碎鼓出、箍筋屈服、刚度退化、试件破坏,最终破坏模式为节点核心区域剪压破坏.通过与课题组其他试验结果对比,外伸式端板螺栓连接型试件耗能增长最快,核心区箍筋、纵筋、混凝土能充分发挥作用,因此外伸式端板螺栓连接型为较合理的节点模式.

To research the mechanical property of steel beam tended end-plate connections, pseudo-static test,low cyclic 1 and concrete column composite joints with ex- oading test,was executed on 7 test specimens, all of which were welded compound-ring-hoop concrete column and cellular steel beam composite joints. The experimental results reflected that the load value was smaller when steel beam and concrete column composite joints crack with extended end-plate connections was appearing; after the test specimens yiel- ded, the main X-type crossing incline shear cracks were appearing in areas of joints; when it came to the stage of destroy, continuous seam appeared in areas of joints core, moreover, part of concrete in those are- as was crushed and plumped, hoops yielded, stiffness degraded, and test specimens were destroyed; final- ly, the destroying pattern in aforementioned areas was shear compression failure. Compared with other experimental results, the fastest energy-consuming test specimen were those that with extended end-plate bol- ted connections, hoops, longitudinal bars and concrete in areas of joints core can fully show their functions. As a result, the extended end-plate bolted connection was a comparatively reasonable pattern of joints.