Assessing Hydrated Cement Paste Properties Using Experimentally Informed Discrete Models

Abstract

Properties of concrete are, to a large extent, dependent on the properties of its binding constituent, hydrated cement paste. Therefore, knowledge of properties of hydrated cement paste is crucial for predicting concrete behavior. This paper presents an experimentally informed approach for modeling elastic and transport properties of cement paste. The models used realistic microstructural informationobtained by X-ray computed tomography-as input for property determination. The properties were then determined using discrete numerical models, namely, models based on a lattice approach. Modeling results were compared with literature data, showing excellent correlations. Furthermore, dependence of properties of cement paste on the total porosity, based on the modeling results, was explored. Finally, a correlation between elastic and transport properties for the explored range of portland cement pastes was established. It is seen that the models can be used for property prediction, but also for exploring correlations between different parameters.

Micromechanical testing and modelling of blast furnace slag cement pastes

“…This could be caused by the refinement of the capillary porosity caused by the hydraulic reactions of slag, since it is known that (tensile) strength is inversely proportional to porosity [71]. An inversely proportional relationship between porosity and elastic modulus has also been reported [43]. A comparison between experimental measurements is given later.…”

“…The voxel resolution under these conditions was 2 Â 2 Â 2 lm 3 /voxel. Although this resolution is not as high as others reported [29,41], it is sufficient to model the fracture behavior of hardened cement paste at micro-scale and consider its heterogeneity [37,[42][43][44]. Reconstructed slices were carried out with Phoenix Datos|x software and a 3D stack of 8-bit cross-section images were generated in the end.…”

Influence of Micro-Pore Connectivity and Micro-Fractures on Calcium Leaching of Cement Pastes—A Coupled Simulation Approach

“…It also shows that the elastic properties mainly depend on the relative amounts of solid and pore phases in the hardened cement paste, and less on the pore connectivity and the pore structure. Moreover, the strength [77] and post-peak behavior of the two simulated microstructures clearly differ. Table 3.…”

“…The heterogeneous nature of hardened cement paste systems is considered by employing a particle overlay procedure (Figure 1b). [77].…”

“…Figure 1. (a) Node and mesh generation procedure; (b) an example of the overlay procedure for cement paste, shown in 2D for simplicity (pink -outer product, red -inner product, light blueunhydrated cement), adapted from[77].…”