The article presents studies’ results of cementless lightweight concretes based on porous granular aggregate. Lightweight concrete components are specially synthesized from mixtures containing liquid sodium glass and thermal energy waste with various fineness. Thermal hardening a matrix technogenic fillers at temperature 350ºС provided heat-insulating 480 kg/m 3 density compressive strength 4.7...

This paper presents a model to simulate chemical degradation of concrete due to leaching. The model considers simultaneously the multi-scale nature of concrete, a thermodynamic description of cement phases, and time-variable transport properties. It is implemented in the generic simulator HP1, which simulates the reactive transport in variably-saturated porous media. To illustrate the capabilit...

Using hot aggregates in concrete making results in drop in compressive strength of the produced concrete. Various methods have been proposed for cooling concrete aggregates. In this paper we propose a modified design for a cooling drum to be used in this regard. Preliminary simulation of the heat flow during the cooling process in the drum is analyzed with the objective of optimizing the design...

We deal with a one-dimensional coupled system of semi-linear reaction-diffusion equations in two a priori unknown moving phases driven by a non-local kinetic condition. The PDEs system models the penetration of gaseous CO2 in unsaturated cement-based porous materials (concrete). The main issue is that CO2 diffusion and fast reaction with Ca(OH)2 in concrete lead to a sudden drop of alkalinity n...

Carbonation is one of the major deteriorations that accelerate steel corrosion in reinforced concrete structures. Many mathematical/numerical models of the carbonation process, primarily diffusion-reaction models, have been established to predict the carbonation depth. However, the mass transfer of carbon dioxide in porous concrete includes molecular diffusion and convection mass transfer. In p...

Cement-based composites are among the most widely-used construction materials due to their low cost, high compressive strength, high durability, versatility, and easy-handling. Unfortunately, cement-based composites are intrinsically porous and may deteriorate as a result of exposure to harsh environments or poor construction quality. Over the last few decades, most research has focused on the ...