基于高强螺栓连接的装配式组合梁推出试验研究
Experimental Study on Push-Out of Prefabricated Composite Beams Based on High Strength Bolt Connection

为适应装配式建筑的发展需求，并实现钢–混组合梁的快速装配化，提出了一种基于高强螺栓连接的装配式组合梁，混凝土板和钢梁可在工厂预制，剪力连接件由高强螺栓和钢盖板组成，通过焊接在钢梁上的凹槽导轨将螺栓滑入到导轨中的指定位置，最后灌入CGM高强无收缩灌浆料，从而完成钢–混凝土组合梁的装配。为研究该高强螺栓剪力连接件的抗剪性能，设计了两个推出试件，通过推出试验对其抗剪性能进行研究，观察试验中试件的破坏形态、荷载–滑移曲线、以及荷载作用下混凝土板的横向分离量。试验和分析结果表明：试件在高强螺栓连接件作用下呈现出良好的组合作用、试件破坏形态为二次灌浆混凝土的局部压溃；横向布置的钢筋在试件抗剪过程中发挥了一定作用；随着混凝土翼板横向分离量的增大，试件的抗剪性能逐渐减弱。可参照我国现行《钢结构设计标准》(GB50017-2020)对该高强螺栓的抗剪承载力进行计算。
In order to fulfill the development needs of prefabricated buildings and to facilitate the rapid assembly of steel-concrete composite beams, an assembled composite beam based on a high-strength bolted connection is proposed. The concrete slab and the steel beam can be prefabricated at the factory. The shear connector consists of high-strength bolts and steel caps. The bolts are pushed through the grooved guide rail welded to the steel beam into the specified position of the guide rail and finally poured into the CGM high-strength non-shrink grout to complete the assembly of the steel-concrete composite beam. In order to study the shear resistance capability of the high-strength bolt shear connector, two push-out specimens were designed and their shear resistance capabilities were studied by push-out test, observing the damage pattern of the specimens in the tests, load-slip curves, as well as the amount of transverse separation of the concrete slabs under the action of the loads. The test and analysis results show that: the specimen shows a good combination under the action of high-strength bolt connectors; the damage pattern of the specimen is the partial collapse of the secondary grouted concrete; the transversely arranged reinforcement bars play a certain role in the process of the shear resistance of the specimen; with the increase of the transverse separation of the concrete flange plate, the shear resistance capability of the specimen is gradually weakened. The shear bearing capacity of the high-strength bolt can be calculated by referring to the current Chinese steel structure design standard (GB50017-2020).