粉状碳纤维-木构件端面复合界面力学特性研究

Wood end is the weakest part in wood members for its less lateral load performance . It is an effective technical means that the powered carbon fiber, with its good properties of tensile and dispersion, is applied to physically strengthen wood member's end, so as to change the weakest status. Carbon fiber to reinforce wood is actually an issue of interface's bond properties and how to transfer interface's stree between the wood's end and powered carbon fibre. The project using microstrain testing technology is to study the carbon fibre reinforced wood's key position interface in the loading process stress transmission path and displacement distribution field. The project provides a theoretic bases for the wood's end face reinforcement; Enhances the further development and improvement model of the control interface, and meanwhile provides theoretical basis of the occurrence of stress concentration. X ray density meter is used to measure density distribution of enhanced wood end area, near the interface cross section. The relationship of the degree of permeability in materials and interface bonding performance is studied.The project is to explore the transfer process of face shear-pull loading process stress under different conditions, and to establish the interface stress distribution and transfer model, and to set up reliable wood endface enhancement model.

木材端部承受横向荷载的能力较弱，在建筑木构件中通常是最薄弱的部位。运用抗拉性能和分散性优异的粉状碳纤维来增强建筑木构件端面是改善木材端部力学性能不足的一种有效的技术手段，碳纤维增强木材端面的问题实质上是复合界面结合性能及应力如何传递的问题。利用微应变测试技术，研究碳纤维与木材端面复合的关键部位界面在受载过程中应力传递路径及位移分布场，旨在为木材端面增强理论和增强模型的进一步发展和完善提供基础保证，为控制界面应力集中的发生提供理论依据。利用X射线密度仪测得木材端部增强区界面附近十字剖面密度分布，研究界面处材料间渗透程度与界面结合性能关系。探索端面剪拉受载过程中及在不同状态下界面应力传递过程，并建立界面应力分布及传递模型，进而建立可靠的木材端面增强模型。

木材端部承受横向荷载的能力较弱，在建筑木构件中通常是最薄弱的部位，易成为开裂破坏的源头。运用抗拉性能和分散性优异的粉状碳纤维来增强建筑木构件端面是改善木材端部力学性能不足的一种有效的技术手段。本课题围绕碳纤维增强木材端面问题的实质即复合界面结合性能及应力如何传递的问题，从木材端面处理与碳纤维改性、端面增强方法与结构及界面应力传递机理三个层面展开研究，找到了能有效增强木构件端部的方法，并有效解决了木材端面湿态碳纤维渗透性问题及涂层均匀施压的问题。建立了木构件端部增强模型，揭示了界面应力分布及传递机理，为促进木材端面增强理论和增强模型的进一步发展和完善提供了基础保证。研究成果对于预防和控制木材端面开裂破坏、提高木结构强度、发挥木材优越性具有重要的意义。