点阵结构木质工程材的结构优化、功能设计与可靠性分析

In this research project, based on the mainly theoretical bases of composite design science and the design idea of structure and function integration, the lattice truss core sandwich structure will be applied to the structural design of the wood engineering composites, and the optimum selection of panel material, core material and topological form will be also get. For achieving the new performance requires such as the reinforcement, high toughness, light weight and multifunction, the high performance wood engineering composite materials with structural-functional integration will be manufactured by structural optimization and functional design. And the optimal structural parameters and functional parameters can be getting by using the theoretical prediction model and experiment verification, as well as the failure mechanisms of composites will be also analyzed at different loading modes, in order to find the failure modes of different lattice structure forms at different loading environments, at last the theoretical prediction model of mechanical properties will be built by the equivalent modulus method, for comparing with the finite element numerical model. In this research project, the vibration mode and vibration performance of wood engineering composites with lattice truss core sandwich structure will be also studied by using non-destructive testing method, in order to evaluate the seismic and damping performance and build the non-destructive evaluation model of mechanical properties. Ultimately, the change laws of reliability of wood engineering composites with lattice truss core sandwich structure will be analyzed to predict their service lifetime at different service environments, in order to provide scientific basis for rational utilization of the wood engineering composites with lattice truss core sandwich structure.

本项目以复合材料设计学为理论依据，从结构与功能一体化设计的思路出发，将点阵结构应用于木质工程材的结构设计中，优选出适用于制备点阵结构的面板材料、芯层材料、拓扑形式等；通过结构优化与功能设计，制备出结构功能一体化的高性能木质工程材，达到增强增韧轻质多功能化的性能要求；采用理论预测模型与试验验证相结合的方式，对点阵结构木质工程材的结构参数与功能参数进行优化设计，分析不同载荷模式下的失效机理，揭示在不同承载环境下，点阵结构形式对力学性能的作用机理及其失效模式，建立基于等效模量方法的力学性能理论预测模型，并与有限元数值模型对比；利用无损检测方法分析点阵结构工程材的振动模态，评价其抗震减振性能，建立基于振动性能的材料力学性能的无损评价模型；揭示点阵结构木质工程材在不同使用环境下可靠性的变化规律，实现点阵结构木质工程材在不同使用环境下使用寿命的预测，为点阵结构木质工程材的合理利用提供科学依据。

木质工程材属于绿色建材范畴，具有较高的强重比和突出的隔热保温、吸音隔声以及自然美观、质感舒爽等环境协调性能，为人类创造了舒适、优雅的生活环境，提高了人们的生活质量。点阵夹芯结构材料是当前国际上认为极具应用前景的新一代先进、轻质、强韧材料，具有更高的比强度和比刚度。本项目围绕复合材料结构与性能可设计的研究思路，对传统的木质工程材料进行了结构的优化与性能的再设计，采用点阵结构对木质工程材进行了结构优化，并在夹芯空隙内填充了功能材料以赋予材料新的功能，最终制备出了结构功能一体化的木质工程复合材，该材料具有低成本、高性能、高附加值的特点，将扩大木质工程复合材的应用领域。本项目围绕木质材料本身的材料特性，将点阵结构引入到木质工程材料的结构设计中，区别于金属点阵结构与复合材料点阵结构的成型工艺，探索出了基于木质材料加工特点的木质点阵结构成型工艺，优选出了木质点阵结构的工艺制备参数，并使用无损检测方法对点阵结构木质工程材的性能进行了评价，为后期在役工程应用的点阵结构木质工程材提供了可靠的检测评价方法与理论依据。本项目全面考虑了蠕变、长期载荷和环境因素对点阵结构木质工程材使用寿命的影响，分析了其在各种使用环境下的时变可靠性，预测了其在各种环境下的使用寿命，为其在承载结构中的安全使用提供了理论依据。