预制装配式木-混凝土斜交螺钉剪力件的受力性能研究

为解决木梁与预制混凝土板之间的界面连接问题，针对预制装配式木-混凝土斜交螺钉剪力件的受剪性能进行了试验与理论研究。共设计了5组推出试验，控制参数包括装配式与现浇式、螺钉直径、螺钉贯入深度以及螺钉布置方式等。试验结果表明：各组试件中螺钉的破坏模式与螺钉长细比密切相关；由于倾斜钢套筒预埋件对螺钉的锚固作用，装配式剪力件的滑移刚度相较现浇式提高了约35%；剪力件的受剪性能随螺钉直径或贯入深度的增加而提升。此外，基于既有斜交螺钉受剪理论，提出了装配式斜交螺钉剪力件的6种理论破坏模式，并将解析理论与半经验公式相结合，给出了剪力件滑移刚度的计算方法。对比理论结果与各组试件破坏模式、承载力和滑移刚度试验结果，两者吻合均良好。

Mechanical behavior of crossed inclined coach screw shear connections for prefabricated timber-concrete composite structures

In order to solve the issue of the interfacial connect between timber beam and prefabricated concrete slab, experimental and theoretical investigations on the mechanical behavior of crossed inclined coach screw shear connections for prefabricated timber-concrete composite (PTCC) structures were conducted. Five groups of push-out tests were designed with the controlling parameters of the fabricated type, screw diameter, screw penetration depth and screw configuration. The test results show that the failure mode of the screws is significantly affected by the slenderness ratio. The slip modulus of the connections for PTCC structures is 35% higher than that of connections for traditional timber-concrete composite (TCC) structures due to the anchoring effect of the embedded inclined steel tubes in the prefabricated concrete slabs. The load carrying capacity of the connection increases with the improvement of the screw diameter or penetration depth. In addition, six types of theoretical failure modes for connections were proposed based on the classical theory for inclined screws. By combining the semi-empirical formula and the analytical theory, the calculation method for determining the slip modulus of this kind of connection was also put forward. It is found that the predicted failure modes, load carrying capacity and slip modulus are all in agreement with those of the experimental results.