多榀木桁架的研究现状与发展趋势

轻型木桁架由于其优异的性能在现代木结构建筑屋盖与楼盖系统以及城市的“平改坡”工程中得到广泛的应用。而在轻型木桁架类别中,除普通单榀木桁架外,还包括多榀木桁架,这种多榀木桁架是由多片单榀木桁架通过连接件组合而成。多榀木桁架一般用于屋盖或楼盖系统中的关键部位,其除受到上部均布荷载外,还受到其他与其搭接的普通桁架传递的集中荷载,其受力环境较普通桁架更为复杂。这种通过多个单榀木桁架组合而成的多榀木桁架也成为现代木结构屋盖、楼盖关键承力节点处最常用的结构形式,有着广泛的应用前景。笔者结合多榀木桁架的连接节点性能、轻型木桁架的承载性能及破坏机理、加载制度和模型模拟等方面的国内外研究进展,总结了该领域的研究热点,并对多榀木桁架今后的发展尤其是多榀木桁架榀与榀之间的连接方式提出了看法。
Light wood truss is widely used in roof and floor systems of modern wood structure buildings and re-roofing projects due to its lightweight, high strength, good seismic performance, simple construction, design flexibility and other excellent characteristics. In addition to the single wood truss which is the most common form of light wood truss, the light wood truss also involves girder truss. The girder truss is composed of several pieces of single light wood truss by connectors and commonly used in key parts of the roof or floor system in modern wood structure buildings and re-roofing projects. It supports even load from upside and the loads from single truss that joint with the girder truss. Since the stress environment of girder truss is more complicated than that of single wood truss, the wood girder truss needs higher bearing capacity. Being composed of several pieces of single light wood truss, the girder truss has become the most common form of structure in key parts of the roof or floor system in modern wood structure, and exhibites broad application prospects. This paper introduced the present research hotspots of wood girder truss and summarized the evolution of wood girder truss in domestic and overseas research, including studies on the connectors of girder truss(consisting of the mechanical performance of metal plat connector and the current style of connection between wood girder trusses), the research findings on the bearing capacity, failure mechanism, the loading systems of wood truss and model simulation of wood girder truss. In the end, the paper put forward some suggestions on the future development of wood girder truss, especially in the style of connection between wood girder trusses