台风作用下低矮建筑风荷载现场实测、风洞实验和数值模拟综合研究与集成

Typhoon is one of the most destructive natural disasters. Typhoon-induced disasters may cause significant economic losses and heavy causalities, most of which result from the collapse of low-rise residential buildings. The proposed project aims to investigate the characteristics of typhoon-generated wind near ground and assess its effects on typical low-rise buildings by field measurements, wind tunnel testing and numerical simulation. This study will be conducted in three closely related phases. Phase 1 will involve the development of our on-going field measurement program, for which two full-scale low-rise buildings with a flat roof and a gable roof have been built and a great deal of instrumentation work has been performed. Both the experimental buildings are located at the coastal sites with high incidence of typhoon winds. The field measurements will be conducted to provide valuable data and information on the near-ground wind characteristics and wind-induced pressures on the full-scale experimental buildings during typhoons. Furthermore, in Phase 2, wind tunnel tests will be conducted to study the effects of wind on the building models at a conventional wind tunnel and a multiple-fan active wind tunnel, respectively. By comparing the model test results with the measured building surface pressures, this study will (1) examine the capability of the model tests to generate extremely high suction pressures on the roof corners and leading edges of the buildings and (2) investigate the effects of the non-stationary flow features of typhoons on the building surface pressures. Afterwards, in Phase 3, computational fluid dynamics (CFD) will be adopted to numerically study the effects of wind on the buildings under typhoon conditions. By comparing the simulation results with the measurements, this study will validate and verify the accuracy and applicability of the numerical simulation methods. This combined field monitoring, model testing and numerical simulation study will enhance our understanding of surface-layer wind structures and the effects of wind on typical low-rise buildings during typhoons in an effort to reduce typhoon wind damages to residential buildings. The output of the project will be important to the wind-resistant design of buildings and structures in typhoon- or hurricane-prone regions such as coastal regions in the south-east China.

台风会造成严重的经济损失和人员伤亡，其中大部分风致灾难是由于低矮建筑物倒塌或破坏造成的。本研究项目旨在通过现场实测、风洞实验和数值模拟的综合手段深入研究近地强/台风风场以及在其作用下低矮建筑的风效应。本项目含三个相关阶段。第一阶段为现场实测，将完善和发展已建立的位于沿海台风频发地区的平屋面和双坡屋面实测房及风场和风压测试系统, 深入系统的开展实测研究;在第二阶段，分别在常规边界层风洞和多排阵列风扇的主动式风洞中开展低矮建筑模型的测压试验;在第三阶段，采用计算流体动力学开展强/台风作用下低矮建筑风效应的数值模拟研究。本项目将结合现场实测，模型试验和数值模拟的综合研究方法加深对近地台风风场及其对典型低矮建筑作用机理的理解并解决其中的一些关键科学问题, 从而减少台风造成的人员伤亡和财产损失。本项目的研究成果将会对台风多发地区（如我国东南沿海地区）的低矮建筑的抗风设计提供宝贵的资料。

本项目采用现场实测、风洞试验和数值模拟方法对热带气旋边界层风场特征及低矮房屋屋面风压特性进行了深入研究。在东南沿海地区建造了三套低矮房屋现场实测系统，包含平坡、双坡和双坡带挑檐三种典型低矮房屋。基于这三套系统，获取了丰富的近地边界层风场数据和低矮房屋表面风压数据，并对近地边界层风场特性和低矮房屋表面风压特性进行了深入研究。另外，基于多个气象观测站点以及多普勒雷达获取的风场数据，研究了热带气旋、季风和雷暴气候中的竖向风剖面特征。在风洞试验方面，以实测房屋为原型，开展了一系列风洞试验，研究了缩尺比和湍流积分尺度对低矮房屋屋面风压的影响；另外，研究了来流湍流对钝体分离和再附区风压的影响。在数值模拟方面，本项目采用大涡模拟方法模拟了复杂屋面的风压分布和周围风场特性。本项目的研究结果解决了边界层风场和低矮建筑表面风压的一些关键科学问题，并可为低矮房屋的抗风设计和我国风荷载规范的修订提供宝贵依据