水泥基材料的化学-力学耦合作用

水泥石良好的粘结性能和力学性能决定水泥基材料和结构的耐久性.通过试验和理论研究,发现水泥石中含钙水化物质,特别是氢氧化钙Ca(OH)_2和水化硅酸钙C-S-H在化学腐蚀作用下的流失是一个复杂的过程.假定水泥基材料为宏观均匀材料,引入考虑两种水化物不同扩散过程的化学扩散模型.提出了新的化学-力学损伤本构模型,描述水泥基材料在不同化学腐蚀下的应力应变关系.综合应用提出的水泥基材料的化学-力学损伤本构关系和化学扩散模型,可以较好地反映水泥石具有时间效应的力学特性.

Chemo-mechanical coupling of cement-based material

Cement-based material has good resistance and it depends highly on the good coherence and mechanical behavior of cement paste. Based on experiment data and theoretical study, it is found that the leaching of calcium ions in calcium hydrates such as Ca(OH)₂₊ and C-S-H is a complex procedure. Assume that the cement-based material is a homogeneous material and based on the different mechanism of the hydrates in the chemical aggression, the diffusion's law is introduced. Referred to the different damage degree, a new chemical damage mechanic constitutive law is presented. In this paper, with the application of the equation of diffusion, a time dependent mechanics modeling can well describe the chemical-mechanical coupling phenomena for cement paste.