Experimental and Analytical Seismic Studies of MRF's and MRF-CBF Dual Systems with Concrete Filled Tube Members

建筑物的复合结构为抵抗非地震（例如重力和风）荷载提供了有效的体系。钢管混凝土柱是组合结构的一种形式。迄今为止，美日地震工程合作研究项目（U.S.-Japan Cooperative research Program on Earthquake Engineering）对cft相关的研究已经调查了单个构件和连接在地震荷载条件下的性能。然而，目前对具有CFT构件和相关连接的完整结构框架的抗震性能缺乏了解。本项目将重点研究CFT结构框架体系的抗震性能。本项目将：(1)研究CFT宽柱翼缘梁MRF的抗震性能；(2)研究了具有CFT柱和CFT支撑的MRF-CBF双框架体系的抗震性能；(3)评估CFT柱宽法兰梁mrf和具有CFT柱和CFT支撑的MRF-CBF双框架系统的分析建模和分析方法；(4)审查和改进具有CFT构件的结构框架系统的设计标准和方法。该项目的目标将通过综合分析和实验调查来实现。分析研究将集中在mrf和MRF-CBF双系统的非线性时程分析上。采用改进的设计准则，将设计三个CFT试验框架。每个测试框架将是为美日合作项目主题结构设计的两舱六层框架的下三层的5/6比例模型。三种框架包括：(1)方形CFT柱和宽翼缘梁的MRF框架；(2)具有方形CFT柱和CFT无粘结支撑的MRF-CBF双体系；(3)具有方形CFT柱和CFT粘结支撑的MRF-CBF双体系。实验调查将在每个测试框架上执行一系列伪静态测试，使用模拟地震载荷，包括在第一层，第二层和第三层施加的侧向位移历史。该项目将获得CFT构件结构体系抗震性能的新知识，这是无法从孤立构件和连接的研究中获得的，并将为设计专业人员提供复合结构体系抗震设计所需的技术信息。本项目由NSF94-154“美日复合材料和混合结构合作研究”项目资助。

Composite construction for buildings provides an effective system for resisting non-seismic (e.g., gravity and wind) loads. Concrete filled steel tube (CFT) columns are one form of composite construction. CFT-related research studies to date under the U.S.-Japan Cooperative Research Program on Earthquake Engineering have investigated the performance of individual members and connections under seismic loading conditions. However, there currently is a lack of knowledge of the seismic performance of complete structural frames with CFT members and related connections.This project will focus on the seismic performance of CFT structural frame systems. The project will: (1) investigate the seismic performance of CFT column-wide flange beam MRF; (2) investigate the seismic performance of MRF-CBF dual frame systems with CFT columns and CFT braces; (3) evaluate analytical modeling and analysis procedures for CFT column-wide flange beam MRFs and MRF-CBF dual frame systems with CFT columns and CFT braces; and (4) review and improve design criteria and methodologies for structural frame systems with CFT members.The objectives of the project will be achieved through integrated analytical and experimental investigations. The analytical investigation will focus on nonlinear time history analysis of MRFs and MRF-CBF dual systems. Using the improved design criteria, three CFT test frames will be designed. Each test frame will be a 5/6 scale model of the lower three stories of a two-bay six-story frame designed for the theme structure of the U.S. Japan Cooperative Program. The three frames include: (1) and MRF with square CFT columns and wide flange beams; (2) an MRF-CBF dual system with square CFT columns and CFT unbonded braces; and (3) a MRF-CBF dual system with square CFT columns and CFT bonded braces. The experimental investigation will execute a series of pseudo-static tests on each test frame using a simulated seismic loading that consists of imposed lateral displacement histories at the first, second, and third floor levels. The project will acquire new knowledge of the seismic performance of structural systems with CFT members that cannot be obtained from studies of isolated members and connections, and will generate technical information needed by design professionals for the seismic resistant design of composite structural systems. This project is supported under initiative NSF94-154 "US-Japan-Cooperative Research in Composite and Hybrid Structures."