考虑位置函数的胶合木植筋粘结-滑移关系研究

胶合植筋技术是一种新型的木结构连接技术,具有承载力高、刚度大、美观且防火效果好等优点,已被成功应用于木结构建筑及桥梁领域。木结构植筋与混凝土植筋类似,涉及到3种材料、2个界面,木材-植筋之间的粘结属多重介质间的粘结问题。木结构植筋节点是否具备良好的结构性能,除了各材料的基本性能有保证外,另外就是界面是否具备良好的粘结性能。该文基于三折线粘结-滑移关系模型,推导了植筋应力、界面粘结应力及相对滑移沿锚固长度分布的解析解,并与试验结果对比,结果表明,理论值与试验值吻合良好。通过实测加载过程中植筋内部的应变及加载端植筋与木材之间的相对滑移,研究了植筋-木材之间的粘结应力及相对滑移沿锚固长度的分布规律,最终建立了考虑位置函数的胶合木植筋粘结滑移关系。

STUDY ON BOND-SLIP LAW OF GLULAM CONNECTION WITH GLUED-IN REBAR WITH CONSIDERATION OF LOCATION FUNCTION

Glued-in rebar technology is a new type of timber connecting technology characterized by high load-carrying capacity, high stiffness, improved aesthetic appearance and good fire resistance, which has been successfully used in the construction of timber buildings and bridges. Glued-in rebar in timber is similar to the post-installed rebar in concrete, in which three types of materials and two interfaces were involved. Bond behavior between glued-in rebar and timber is an issue of bond among several mediums. For good structural performance, material properties of glued-in rebar timber connection should be guaranteed. Furthermore, good bond performance at different interfaces is required. In this paper, based on the tri-linear bond-slip model, the closed-form solutions of axial stress of glued-in rebar, interfacial bond stress and relative slip were obtained by theoretical derivation and were then compared with the experimental results. The results showed that theoretical values fit the experimental data well. Distribution of bond stress and relative slip along the anchorage length were analyzed using the strains of glued-in rebar and the relative slip at the loaded end recorded during the testing. Finally, the bond-slip relationship for glued-in rebar glulam connection related to location function was established.