木钉焊接框架剪力墙受力机理与设计计算方法研究

Wood nail welding is a kind of new green connection technology which is fabricated by wood nail welding into wood component generating heat by high speed friction. Several researchers have been conducted to study the basic bonding mechanism of this connection technology, but the analytical models of calculating the load-bearing capacity, stiffness for the single-wood nail welding joint and the synergistic effect of multiple-wood nails welding joint are rarely seen. The application proposed the researches of forced mechanism, theoretical calculation and design method of wood nail welding frame shear wall based on the non-gluing mechanism and the synergistic effect mechanism. This project plans to study the wood nail welding by the method of experiment, modeling and analysis, which including: 1) the load-bearing capacity and failure mode of wood nail welding joint under the unidirectional stress; 2) the analytical models of calculating the load-bearing capacity, stiffness for the single-wood nail welding joint subjected to compound stress will be proposed by analyzing the load-bearing capacity and failure characteristics; 3) the coefficient relation between single-wood nail welding joint and multiple-wood nail welding joint will be investigated by studying the synergistic effect of multiple-wood nails welding joint; 4) the design method and theoretical calculation will be proposed with optimization model design by analyzing of the load-bearing capacity of wood nail welding frame shear wall. Through the researches in this project, the analytical models of calculating the load-bearing capacity, stiffness for the single-wood nail welding joint and the model, theoretical calculation and design method of wood nail welding frame shear wall are expected to be developed. It would provide the reliable theoretical basis for the engineering application.

木钉焊接是一种将木钉通过高速摩擦生热打入木构件中的新型绿色连接技术。目前，有学者对该连接技术进行一些基本结合机理的研究，但对木钉焊接节点承载和刚度模型建立以及多杆群组节点的协同效应研究还基本处于空白。申请人基于无胶胶合机理和协同作用机制，提出木钉焊接框架剪力墙受力机理、理论计算与设计方法的研究。本项目拟通过试验、数值模拟和理论分析对木钉焊接进行研究，包括：（1）单向应力状态下木钉焊接节点的承载力与破坏模式；（2）复合应力状态下木钉焊接节点的承载力与破坏特性，建立木钉焊接节点的承载力和刚度理论计算模型；（3）多杆木钉群组焊接节点协同作用机制，建立单杆和多杆焊接节点承载力之间的系数关系；（4）木钉焊接框架剪力墙的承载性能，优化模型设计，提出设计方法和计算公式。通过研究，建立木钉焊接节点承载力和刚度理论计算模型及框架剪力墙承载模型、形成设计和计算方法，为工程应用提供可靠的理论基础。

本项目主要研究框架剪力墙的相关性能，发现木钉不能作为覆面板和框架的连接件，但是可以制备木钉连接层积材作为组合梁柱框架，同时开展了木钉连接正交层积材作为墙体的承载性能分析。另一方面，针对L型组合梁柱框架节点的承载特征，开发了木-自攻螺钉复合榫，进行了单杆、多杆连接节点承载力分析并建立相关的计算方法和有限元模型，进一步开展L型节点的承载力分析并建立相关的计算方法和有限元模型，最后以木钉连接层积材作为墙体组合梁柱框架，框架端部节点采用复合榫连接，开展复合榫连接组合梁柱门式框架的承载力分析。所以本项目主要开展了木钉和复合榫连接节点、框架墙体两方面的研究。.在木钉连接方面：.1）开展了木钉连接节点的承载力分析，明确木钉连接节点承载力的计算可以参考木结构设计手册中的销连接部分；.2）将木钉连接用于制备层积材，作为组合梁柱使用，通过全部承压和局部承压两种承载方式，分析木钉连接层积材的抗弯性能；.3）开展了木钉连接常规轻型木结构剪力墙的承载力研究，分析木钉在无抗拔紧固件轻型木结构标准墙的应用可行性，发现易引起覆面板的剥离脱落，导致事故发生；.4）木钉可用于本项目提出的采用新T型抗上拔紧固件的夹心墙连接，相关的性能均优于采用常规抗上拔紧固件的轻型木结构标准墙；.5）木钉连接正交层积材可以作为墙体使用，性能与常规胶合连接正交层积材相当，并提出了相关的承载力和位移计算方法，相关的有限元模型也验证了试验和理论计算的可行性。.在复合榫方面：.1）提出木-自攻螺钉复合榫，并明确木榫和自攻螺钉作为个体在复合榫承载过程中发挥了协同作用；.2）提出复合榫单剪承载力计算公式，并明确单杆和多杆之间的参数关系，通过有限元模型分析发现承载力试验值、理论计算值和模拟值之间具有良好的吻合型；.3）提出复合榫连接L型构件承载力计算公式，并建立有限元分析模型；.4）应用复合榫连接门式框架，发现其与常规钢插板-螺栓连接门式框架性能相当。