Fire Resistance of Concrete Filled Steel Tube Column and Spalling Analysis

时间：2017年6月20日下午14:00

地点：地坤楼409

报告人：姚尧教授

主持人：肖岩教授

报告内容：

Concrete filled steel tube (CFST) columns have been widely applied in modern construction. In the current study, computational model was developed to simulate the behavior of CFST columns exposed to non-uniform and natural fire conditions. The failure mechanism of CFST columns under non-uniform fire was discussed. Parametric studies were conducted to investigate the influence of critical structural parameters. A theoretical approach was proposed to predict the fire resistance of CFST columns exposed to non-uniform heating. On the other hand, excessive internal pressure and high temperature are the key reasons for concrete spalling and there are complex interactions between these two aspects. A multiaxial plastic-damage constitutive model for concrete at different temperatures is proposed. The developed model combines damage mechanics and elasto-plasticity theories based upon a thermodynamic framework. A fourth-order damage tensor is adopted to describe the unilateral effect. A pressure-dependent damage evolution is considered to characterize the behavior of concrete at highly confined stress states. Transient creep and thermal strains are included to account for the thermal response. The proposed constitutive model obeys the thermodynamics laws, and numerical simulations are conducted to validate the developed model. The numerical predictions show good accuracy compared with the experimental results.

报告人简介：

姚尧，西北工业大学力学与土木建筑学院教授、博士生导师。本科、硕士、博士分别毕业于同济大学、新加坡南洋理工大学、美国西北大学土木工程系。曾任美国美孚公司高级研究员、工程专家等职。目前发表学术论文100余篇，其中包括《Journal of Structural Engineering-ASCE》，《Engineering Structures》，《Journal of Engineering Mechanics-ASCE》，《Thin-Walled Structures》，《Journal of Constructional Steel Research》，《International Journal of Plasticity》，《International Journal of Solids and Structures》，《Engineering Fracture Mechanics》，《Rock Mechanics and Rock Engineering》，《Acta Materialia》，《Physical Review B》等本领域知名SCI期刊60余篇，他引400余次。发表英文书章3章。多次担任ASCE EMI、IMECE、MS&T等国际学术会议的分会主席，并作大会邀请报告。担任10余种国际SCI期刊及美国ACI规范评审人。目前，任美国岩石力学学会编委会委员；美国土木工程学会、机械工程学会等协会会员；中国力学学会高级会员；ABAQUS断裂研究国际专家组成员。教育部科学技术进步奖、陕西省科技重大专项、自然科学基金、科技部国际合作等项目评审专家。2016年获陕西省青年科技奖、2017年获陕西高等学校科学技术一等奖（排名第一）。担任国际期刊《Rock Mechanics and Rock Engineering》编委，《Journal of Micromechanics and Molecular Physics》副主编。