Micro- and macro mechanical characterization of contact zones (ITZ) in recycled concrete and development of a multi-scale approach model (MiMaCMo)

该项目的方法是将最新的分析方法(高分辨率、层析、电子显微镜分析、激光烧蚀和纳米压痕)与微观机械建模相结合。这使得以一种全新的质量研究界面过渡区(ITZ)的机械性能、结构和相组成作为各种参数的函数成为可能。得到的实验结果直接输入到了细观力学模型中。这种结合的方法使得从根本上了解R型混凝土的性能并使其具有可预测性成为可能。从得到的信息可以得出结论，再生骨料的各种性质对界面层形成的影响，以及骨料的更好的制备和前处理。根据微观结构的发现，应该可以解释混凝土宏观材料性能的变化。实验工作构成了基础，因此将开发一种多尺度建模方法。与必须针对不同材料重新校准的经验方法不同，多尺度建模允许更广泛地应用于不同类型的R-混凝土。

The approach of the proposed project is to combine the latest analytical methods (high-resolution, tomographic, electron microscopic analysis, laser ablation, and nanoindentation) and micromechanical modeling. This makes it possible to investigate the mechanical properties, structure, and phase composition of the interfacial transition zone (ITZ) as a function of various parameters in a completely new quality. The experimental results obtained find direct input into the micromechanical modeling. This combined approach makes it possible to fundamentally understand the properties of R-concretes and make them predictable. From the information obtained, conclusions can be drawn on the influences of various properties of the recycled aggregates on the formation of the ITZ and on better preparation and pre-treatment of the aggregate. Based on the microstructural findings, it should be possible to explain variations in the macroscopic material behavior of the concretes. The experimental work forms the basis, as a result of which a multi-scale modelling approach is to be developed. In contrast to empirical approaches, which have to be recalibrated for different materials, multi-scale modeling allows for more general application to different types of R-concrete.