MULTISCALE MODELING OF ALKALI SILICA REACTION DEGRADATION OF CONCRETE
Concrete infrastructures, especially those subject to wet environments (R.H.> 80%) are usually endangered by Alkali silica reaction (ASR).Inside concrete meso-structure, water transports alkali ions from cement paste into the aggregate, which react with the available non-crystalline silica inside each aggregate piece.The reaction product (ASR gel) imbibes additional water causing swelling and cracking, resulting in degradation of concrete mechanical properties.ASR is a complex, multi-scale chemo-mechanical problem driven by various environmental factors including humidity and temperature.The physics involved in diffusion and permeability inside concrete play a fundamental role in defining the kinematics, rate and extent of ASR.This paper extends the ASR-LDPM model which models ASR at the aggregate level to account for variable humidity conditions and combines the mechanical behavior of concrete with ASR, creep and shrinkage induced deformations.Finally, to solve large-scale structures, this micro-scale process is coupled into the Homogenized Lattice Discrete Particle Model (H-LDPM), which is a constitutive equation obtained by the mathematical homogenization of LDPM, a discrete model capturing various features of concrete internal heterogeneity with superior modeling and predictive capabilities under various quasi-static and dynamic loading.The capabilities of this approach are validated with reference to experimental data from the literature.
Gianluca Cusatis Mohammed Alnaggar Roozbeh Rezakhani
Civil and Environmental Engineering Department,Northwestern University,USA Civil and Environmental Engineering Department,Rensselaer Polytechnic institute,USA
国际会议
The Fourth RILEM International Symposium on Concrete Modelling (CONMOD 2014)(第四届RILEM混凝土材料建模国际会议)
北京
英文
432-439
2014-10-12（万方平台首次上网日期，不代表论文的发表时间）