Description of anisotropy and chemo-mechanical interaction in porous materials

这项研究与描述一类多孔材料的非弹性变形有关。重点放在两个基本问题上，即机械性能的各向异性和与化学-机械相互作用有关的退化现象。主要应用领域涉及结构力学和地质力学。因此，固有各向异性的主题将在宏观上是不均匀的材料的背景下讨论；特别是结构砖石和钢筋混凝土。本文将首先对砖砌体的非弹性变形进行描述。将开发一个连续统公式，并通过细观力学分析确定所涉及的材料功能。该宏观框架将用于评估魁北克北部水力发电设施的关键砌体部件的地震稳定性。还将在埋设钢筋的混凝土的力学响应建模方面进行进一步的研究。这里，再一次，将采用微观/宏观机械耦合的方法。这项研究将与核工业特别相关，特别是对承受极端机械/热载荷的核安全壳结构的结构完整性的评估。然而，由于化学作用，许多天然材料和人造材料的机械性能都会显著下降。这项研究将主要集中在白垩岩在化学-机械耦合作用下的变形特性的模拟。这种降解现象将归因于晶间压力溶解。这是一个发生在颗粒接触处的非平衡过程，包括固体物质通过间隙流体的扩散传输而溶解和去除。将制定一个总体的宏观框架。将使用均化程序来描述潜在的物理化学过程。这里的主要应用领域是石油工程。

This research is related to description of inelastic deformation in a class of porous materials. The emphasis is placed on two fundamental issues, i.e. that of anisotropy of mechanical properties and the degradation phenomena that are linked to chemo-mechanical interaction. The primary areas of application involve structural mechanics and geomechanics.    The topic of inherent anisotropy will be addressed in the context of materials that are heterogeneous on the macroscale; in particular, structural masonry and reinforced concrete. The research will focus first on the description of inelastic deformation of brick masonry. A continuum formulation will be developed and the material functions involved will be identified through a micromechanical analysis. The macroscopic framework will be applied to assess the seismic stability of critical masonry components of hydroelectric power generation facilities in Northern Quebec. Additional research will be conducted in the area of modeling of mechanical response of concrete with embedded sets of reinforcement. Here, again, a coupled micro/macro-mechanical approach will be pursued. The research will be particularly relevant to the nuclear industry, especially to the assessment of structural integrity of nuclear containment structures subjected to extreme mechanical/thermal loads.    A number of natural and manufactured materials undergo a significant degradation of mechanical properties as a result of chemical interaction. The research will focus mainly on modeling of deformation characteristics of chalk in the presence of chemo-mechanical coupling. The degradation phenomenon will be attributed to intergranular pressure solution. This is a non-equilibrium process that occurs at the grain contacts and consists of dissolution and removal of solid material by diffusive transport through the interstitial fluid. A general macroscopic framework will be developed. A homogenization procedure will be employed to describe the underlying physico-chemical processes. The primary area of application here is the petroleum engineering.