多层轻钢龙骨式复合剪力墙结构体系创新、基础理论与设计方法研究

As a natural green and industrial building, the low-rise cold-formed steel (CFS) structure has been widely used in American, Canada and Australia. However, the developing of mid-rise CFS structure should be more consistent with Chinese national condition than the low-rise CFS structure, due to the large population of our country. The present program mainly involves the following three parts: .A..Based on the innovative research on the structure system and major components, a new CFS shear wall structure system is developed and suitable to the mid-rise buildings which are less than 6 stories. .B..The key fire-resistance problems of such structure system will be solved systematically. Firstly, a simplified thermo-mechanical model for CFS wall and floor assemblies will be put forward and can be used to the prediction of time-dependent deflection, failure mode and fire resistant rating of such assemblies under fire conditions. Furthermore, a practical design method for the fire resistance of CFS wall and floor assemblies will be clearly presented and should meet the requirement of our current code for the fire protection design of buildings. In addition, the experimental and numerical method for the whole CFS structure under fire conditions will be explored and put forward. Based on those researches, the fire-induced damageable zone can be identified from the structure level..C..A series of key problems for the collapse resistance of such structure system subjected to severe earthquakes will be investigated systematically, including the simulation of collapse behavior using DEM/FEM model, the collapse mechanism study based on the vulnerability and sensitivity theory, the prediction of collapse modes by using cellular automata method and the corresponding anti-collapse design method..The research ideas of present program is firstly developing an innovative CFS structure system and then focus on the key fire-resistance and aseismic problems of such system from the view of applied fundamental research. The proposed research results will provide the theoretical and technical support for the engineering application.

广泛应用于发达国家的低层冷成型钢建筑是天然的绿色、工业化建筑，但我国地少人多，发展多层轻钢建筑更符合中国国情。本项目涉及3方面内容：A. 通过体系和主要部件创新，提出适用于6层及以下的多层轻钢龙骨式复合剪力墙结构体系；B. 系统解决该体系若干抗火关键问题：提出热-力耦合作用下新型复合墙体、楼盖变形、破坏模式、耐火时间预测的理论模型；明确给出墙体与楼盖满足现行抗火设计规范的实用设计方法；探索该体系整体抗火试验与数值模拟方法，从结构层面识别火灾环境下的易损部位；C. 系统解决该体系若干强震抗倒塌关键问题：采用DEM/FEM耦合模型实现结构倒塌过程仿真；基于响应敏感性的冗余特性方法揭示结构倒塌机理；采用细胞自动机方法实现该体系倒塌模式的预测；提出该体系强震抗倒塌设计方法。本项目总体研究思路是首先提出新体系，再从应用基础研究角度着重解决其中的2方面关键问题，为其应用于工程实践提供理论与技术支撑。

轻钢房屋建筑结构体系是天然的绿色与工业化建筑，在欧美、澳洲、日本等国家的低多层民用建筑领域应用广泛。我国地少人多，发展多层轻钢房屋建筑更符合国情。本项目旨在解决由低层轻钢房屋建筑扩展至多层所涉及的结构体系及其抗震、抗火、模块化施工问题：.（1）通过体系和主要部件两个层面的创新，提出新型轻钢龙骨式复合墙体、组合楼盖及节点形式，形成多层轻钢龙骨复合剪力墙结构体系，进而发展其模块化施工技术。.（2）完成了千余次冷成型钢及其自攻螺钉连接件高温力学性能试验、常用建筑板材及其保温材料高温热物理特性试验，提出了相应计算模型；完成了数十片新型墙体及楼盖耐火试验，揭示了复合墙体及楼盖的受火失效机制与破坏机理；提出了火灾下该类墙体（楼盖）温度场与变形分布规律、耐火时间与破坏模式预测的简化理论模型与仿真分析模型；提出了实用抗火设计方法与构造措施。.（3）完成了国内首例轻钢龙骨房屋足尺模型真实火灾倒塌试验；提出了受限空间火灾室内全过程非均匀升温曲线计算公式；提出了基于构形易损性理论的结构抗火设计最不利火灾场景预测方法；提出了改进式静-动转化分析法，实现了轻钢房屋整体结构热力耦合数值仿真；进而提出了轻钢整体结构的性能化抗火设计流程。 .（4）完成了五层轻钢结构分层次振动台试验；提出了适用于多层轻钢整体结构抗震模拟的简化数值方法；提出改进式构形易损性理论方法；基于响应敏感性分析方法实现了多层轻钢复合剪力墙结构的冗余特性研究；进而分别从构形易损性和冗余特性角度揭示了该类结构强震倒塌机理；以此为基础，提出了多层轻钢结构“强框架弱墙板”抗震设计理念和强震抗倒塌设计建议。.项目执行过程中发表SCI收录论文45篇、EI收录论文15篇、授权发明专利14项、软件著作权1项，主编轻钢领域标准规程3部，完成轻钢结构工程技术示范1项。