高温下混凝土热-湿-气-力学耦合行为数值模拟

随着混凝土,特别是高性能混凝土(HPC)的推广和应用,建立其在许多不同工程和自然条件下的模型,数值模拟其中发生和发展的物理-化学现象与耦合过程,具有重要科学意义和经济效益.将混凝土模型化为非饱和多孔多相系统,基于含有多相流体的变形多孔介质的质量、动量和能量守恒方程和已有的研究工作,采用有限元法数值模拟了高温下(低于孔隙水的临界温度647.3K)混凝土热-湿-气-力学耦合行为,分析了这一复杂过程中的控制机理.为进一步完善高温下混凝土多相全耦合数值模型打下较好的基础,为防火减灾工程设计提供一定的参考.

Numerical Modelling of the Coupled Thermo-Hygro-Mechanical Behavior of Concrete at High Temperature

With the wide and increasing applications of concrete, especially the high performance concrete (HPC), it is of critical importance in science and economy to establish a mathematical model to simulate the coupled, multiphysical-chemical processes, which occur and develop in concrete. Concrete is modeled as a deforming porous medium unsaturated with multiphase pore fluids, based on mass, momentum and energy conservation equations for the multiphase system and existing work published in literatures, the coupled thermo-hygro-mechanical behaviors occurring in concrete at high temperature (below the critical point of water 647.3K) are numerically simulated by means of the finite element method, the mechanisms of the complex procedures are analyzed, which is the basis of further proving numerical model of the coupled multiphase for concrete at high temperature, fireproofing and disaster reduction.