复杂山地条件下的超高层建筑风效应及气动优化研究

The mountainous cities such as Chongqing etc. have witnessed the rapidly increasing trend of super-tall buildings in recent years. However, the topographic effects can influence both the wind velocities and veering winds, thereby resulting in the asymmetric wind loads and probably significant torsional moments. Furthermore, the wind characteristics are quite complex under the hilly terrain conditions. Consequently, it is of great urgency to improve the wind-resistant performance of super-tall buildings under complex terrain conditions. This proposed study aims to investigate the wind effects and aerodynamic optimization of super-tall buildings under complex terrain conditions by combining the field measurements, wind tunnel tests and numerical simulations. And the proposed study is composed of four closely related tasks. Task 1 is to study the wind characteristics under complex terrain conditions and develop the veering wind model on the basis of the established field measurement platform. Task 2 is to elucidate the effects of veering wind on the aerodynamic forces of super-tall buildings by the wind tunnel tests. Task 3 is to perform the high-fidelity simulations of topographic effects on the super-tall buildings under complex terrain conditions in the cross-validation against the corresponding field data and experimental measurements. Task 4 is to propose the data fusion algorithm of the CFD-driven deep learning for the aerodynamic optimization of super-tall buildings under complex terrain conditions. The outputs of the proposed study will further our understanding of wind characteristics over complex terrains, reveal the mechanism of veering winds on the aerodynamic forces of super-tall buildings, and enhance the wind-resistant optimization design of super-tall buildings.

近年来重庆等山地城市出现越来越多的超高层建筑，而山地环境不仅影响风速，也使得风向沿垂直方面偏转明显，这将导致超高层建筑出现显著的非对称荷载和扭转荷载。因此，亟需针对山地风场下的超高层建筑抗风性能开展研究。本项目采用现场实测、风洞试验以及数值模拟综合研究方法，研究复杂山地条件下的超高层建筑风效应作用机理及气动优化方法。主要研究内容包括：①基于山地风场现场实测平台，获得山地风场特性并发展偏转风（风向角垂直变化）模型；②根据山地风场模型，采用风洞试验研究风向偏转对超高层建筑气动力的影响；③发展针对山地风场下超高层建筑风效应的高保真数值模拟方法，并结合现场实测和风洞试验进行验证；④研究深度学习与数值模拟数据融合算法，提出超高层建筑一体化气动优化方法。本项目的研究成果将加深山地风场特征的理解，揭示偏转风对超高层建筑风效应的作用机理，完善超高层建筑抗风优化设计方法，具有重要的理论和工程实际意义。

本项目针对复杂地形影响下工程结构风效应评估的需求，紧密围绕复杂风场下工程结构风效应评估和模拟方法开展研究。以非稳态的大涡模拟湍流模型为基础进行数值仿真，建立了理想山地湍流风场的精细化大涡模拟方法框架，并基于深度学习方法建立了能处理风速时空信息的多点风速同步预测神经网络模型。同时，本项目结合风洞试验和数值模拟，开展了偏转风场下不同长宽比超高层建筑气动荷载及气弹响应研究，揭示了偏转风场对超高层建筑的作用机理。此外，本研究发展了大气边界层湍流风场生成技术、建筑气动荷载模拟技术，建立了结构风效应评估云计算平台。本项目的研究成果为复杂山地条件下高柔建筑结构风效应评估提供坚实的理论基础和实用的技术手段。