基于风致开孔的低矮房屋风灾易损性分析

With the continuously development of construction in China, light-frame low-rise buildings are widely used in the constructions such as residence, industrial buildings and other infrastructures because of its good load-capacity property and low construction cost. Nevertheless, the low-rise building is very vulnerable in strong winds and often the building envelope suffers severe damage. The wind hazards for low-rise buildings in coastal areas of China are very common. Hence, it is necessary to carry out a research on the wind-induced damage of low-rise building. The project conducts a systematic research to propose a method for vulnerability assessment on wind-induced damage of low-rise building. By means of wind tunnel test and parametric modeling, a probabilistic model describing the landing point of windborne debris is proposed. Then a windborne debris-related hazard model is established which is applicable for vulnerability assessment. Based on theory and estimation approaches for the extreme value, a high-efficient and accurate estimation approach towards extreme wind loads is proposed to improve the performances in failure judgements of envelope components. To incorporate the randomness of wind-induced openings and to provide reasonable hazard predictions, a method for vulnerability assessment on wind-induced damage of low-rise building considering the opening conditions is put forward. The prospective of the project is explored. The project can provide guidance for improving the wind-resistant performance of low buildings, and is of practical and engineering significance.

随着我国建设水平的不断提高，轻质框架低矮房屋由于其承载能力强、建造成本低等特点，被大量用于民宅、厂房以等各类基础设施的建造。另一方面，低矮房屋围护结构在强风环境中极易遭受严重破坏。在我国沿海地带，低矮房屋的风灾案例更是屡见不鲜，因此低矮房屋的风致破坏问题亟待研究。本项目针对低矮房屋风灾易损性的分析方法开展系统性研究。利用风洞试验与参数化建模手段，提出飞掷物落点的概率模型，并建立适用于低矮房屋易损性分析的飞掷物灾害模型。总结并归纳现有极值理论及分析方法，提出具有精确性以及高效性的风荷载极值估计方法，提升围护结构构件的失效判断效率。针对风致开孔的随机性，提出考虑开孔工况的低矮房屋易损性分析方法，对房屋风灾损失做出合理估计。最后探索项目的应用前景。项目研究成果可为低矮房屋抗风性能提升提供方法指导，具有重要的现实意义和工程价值。

我国城镇化进程如火如荼，轻质框架低矮房屋由于其承载能力强、建造成本低等特点，被大量用于民宅、厂房以等各类基础设施的建造。与此同时，低矮房屋的围护结构在台风等强风作用下中极易遭受严重破坏。在我国东南沿海地带，低矮房屋风灾案例屡见不鲜，因此低矮房屋风致破坏的机理和预测亟待研究。针对当前研究的薄弱之处，本项目从飞射物灾害模型、风荷载灾害模型、易损性分析方法等方面开展了系统性的研究，取得了如下成果：（1）精细化预测飞射物三维运动轨迹，提出了飞射物运动轨迹的精确高效数值模拟算法，揭示了飞行能力和气动外形对飞射物运动的影响。（2）完善风荷载极值相关结构和多元建模理论，提出了风荷载极值秩相关性表述方法，建立了风荷载极值高维概率模型。（3）有效量化含随机-区间变量的系统不确定性，提出了多变量系统输出高阶矩的快速算法，并提出了数据不充足条件下的系统参数量化及系统不确定性分析方法。（4）从构件层次预测低矮房屋风灾损失，提出了基于随机开孔工况的围护结构风致易损性分析方法，有效分析了台风过境期间房屋围护结构时变易损性。项目可为房屋结构抗风性能提升提供理论及方法参考，并对职能部门提供防灾减灾工作指导依据。在项目周期中，研究成果在建筑业屋盖性能评定、保险业不动产赔付评估得到了应用，探明了本项目的应用前景和成果落地。