风力雪载下的树木断裂行为与强度诊断新技术

Huge damages would be brought to forest ecology and forest production by wind/snow disaster, what’s more, urban trees and old-age famous trees would also fracture and fall where the safety of people around would be threatened. Therefore, the ability of trees in forest to resist the wind/snow disaster needs to be evaluated to guide forest production, meanwhile, the wind speed and snowpack volume that urban trees and old-age famous trees with hidden troubles can bear should also be known, and so protection would be carried out at an early date. However, complete theory and techniques to solve the problems above haven’t been developed at home and abroad.. In this project, the fracture failure behavior and mechanism of trees under wind and snow loads will be studied and a new strength analysis method of tree will be perfected based on the characteristics of biomaterial and the dynamic and fracture mechanics principles of trees. And a new technique “Tree Black Box” will be developed due to the identification of damage ways and damage factors. It could be used to disgnose the strength of tree and evaluate the ability of tree to resist the wind/snow disaster. The project achivements will promote the research on the forest meteorological disaster, meanwhile, there would be great significance for the protection of forest resources and the development of pretection forest.

风/雪灾害会对森林生态和林业生产带来巨大损害，城市行道树和景区古树也会因此而断裂倒伏并威胁周围人的安全。为此，我们需要评估林区树木抵抗风/雪灾害的能力以指导营林生产、也需要知道带有隐患的行道树或古树名木能够承受多大的风力雪载以便及早采取防护措施，但目前国内外尚未建立起解决上述问题的完备的理论与技术。. 本项目将基于树木生物材料特性、应用树木动力学和断裂力学原理研究树木在风力雪载下断裂破坏行为和机制，完善或补充新的树木强度分析方法，并通过对树木破坏方式及破坏因子识别的基础上研发一种“树木安全黑匣子”的新技术，用于树木强度诊断和林区抗风/雪灾害能力的评估。项目成果能够促进森林气象灾害的研究，并对林木资源保护和防护林建设具有重要意义。

风/雪灾害会对森林生态和林业生产带来巨大损害，城市行道树和景区古树也会因此而断裂倒伏并威胁周围人的安全。为此，我们需要评估林区树木抵抗风/雪灾害的能力以指导营林生产、也需要知道带有隐患的行道树或古树名木能够承受多大的风力雪载以便及早采取防护措施，但目前国内外尚未建立起解决上述问题的完备的理论与技术。. 我们在国家基金“风力雪载下树木断裂行为与强度诊断技术”的资助下，通过几年的紧张工作，我们已经完成研究目标：（1）发明了树木力学量全量测试技术，提出了 “任意风向下的最大弯曲应变”、“树木扭转剪应变”和“雪载荷下的最大应变”的测量方法，而这些在国外迄今未能解决；（2）建立了新的树木强度分析理论和诊断方法，并实际预测了树木能够承受的最大风速；（3）研制了国内外第一台用于树木强度监测分析仪器，并开发了相应的预测分析软件和手机监控APP。（4）已将新获得的树木强度分析的理论与技术用于黄山迎客松的强度监测和上海市区行道树的抗台风能力预测。