Response of mass timber elements subjected to full burnout fires

我建议研究的题目是“大量木材构件在完全烧毁火灾下的反应”。这被认为是一个重大的研究空白，目前正引起科学和工业文献的相当大的兴趣，因为它给设计师和工程师带来了不确定性和挑战。火灾衰变阶段和木材构件的冷却阶段的相互作用对大量木材结构构件的剩余结构能力具有至关重要的影响，从而影响建筑的整体稳定性。当涉及到木材在负载和冷却时的材料响应时，仍然有许多无法解释的现象。在结构工程方面，大量木材构件在加热和冷却后的强度和刚度恢复将被用来确定木材在火灾后恢复到什么程度。由于大量木材构件是复合材料，因此粘接性能的评估将是对本研究的补充。最后，在对冷却阶段的结构进行分析时，常常忽略了水分的影响。在木材没有烧焦或热解的情况下，含水率的变化可能会产生相当大的负面影响，甚至超过高温的影响；这一方面也将被分析。拟议的研究分析将包括3个阶段。计划在第一阶段进行广泛的文献综述。第二阶段将包括实验工作，其中将在加热和负载的情况下进行中小型试验。最后，在第三阶段，将对结果进行参数分析和讨论，并将开发和使用预测模型来制定实用的设计和分析指导，供工程师使用(这是最大化研究影响所必需的)。研究的每一步的总结和实现，以及预期的工作发布或演示，将与项目的监督人员进行周到的沟通和指导。有关恢复阶段大量木材构件性能的知识将通过解决重要的消防安全风险和火灾后性能来加强可持续建筑的安全设计。

The title of my suggested research topic is ''Response of mass timber elements subjected to full burnout fires''. This is recognised as a significant research gap that is attracting considerable interest in the scientific and industrial literature at the moment, due to the uncertainties and challenges that it poses for designers and engineers.The interaction of fire decay phase with timber elements' cooling phase has critically important impacts on the residual structural capacity of mass timber structural elements, and hence affects the overall building stability. There remain many unexplained phenomena when it comes to the material response of timber under load and when cooled. In terms of structural engineering, measuring the strength and stiffness recovery of mass timber elements after it has been heated and cooled will be used to determine to what extend timber recovers after a fire. Since mass timber elements are composites, the assessment of the adhesive performance will be a complementary addition to this study. Finally, the influence of moisture is often overlooked when analysing structures in the cooling phase. Where the timber is not charred nor pyrolyzed, the change in moisture content can have a considerable negative impact, even beyond that of elevated temperatures; an aspect which will also be analysed.The proposed research analysis will consist of 3 stages. An extensive literature review is planned for Stage 1. Stage 2 will include experimental work where small - and medium-scale tests will be performed under the application of heat and load. Finally, in Stage 3, a parametric analysis of the results will be performed and discussed, and predictive models will be developed and used to develop practical design and analysis guidance for use by engineers (which is necessary to maximise research impact).Conduction and realisation of every step of the research, as well as the intended work publication or presentation, will be thoughtfully communicated with and guided by the supervisors of the project.Knowledge about the performance of mass timber elements in recovery phase will enhance the safe design of sustainable buildings by addressing the important fire safety risks and post-fire performance.