Soils stabilized by cement are found to be influenced by the environmental condition such as acid rain, seawater invasion, or industrial pollution. These adverse effects will lead to the deterioration of a structure. In order to study the process of corrosion effects including the changes of the corrosion rate of the surface, compression strength of the cemented soils and the Mg2+ and SO42- ion concentrations of the corrosive solutions have been determined. A series of experiments were conducted on the cemented soil blocks cured with different concentrations of MgSO4 solution. Specifically, the experimental work includes photo documentation, compressive strength tests and measurements of Mg2+ and SO42- ion concentrations. The test results show that the rate of corrosion for the sample surface increases with increasing concentration of the corrosive solution, while, the compressive strength decreases accordingly. Moreover, the corrosion rate degree intensifies with corrosion time. Chemical analysis of the corrosive environment indicates that CaSO4 reacts with the cemented soil, resulting in crystallizing corrosion products of 3 CaO × A12O3 × 3 CaSO4 × 32 H2O and CaCO3 × CaSO4 × CaSiO3 × 15 H2O. Mg(OH)2 reacts with 3 CaO × 2 SiO2 × 3 H2O (C-S-H) and forms new dissolving corrosive reactants such as MgO × SiO2 × H2O (M-S-H). It is concluded that the corrosion of cemented soils in MgSO4 solution is a complex reaction involving the resolving and crystallizing corrosive processes. Finally, a strength model for cemented soils is proposed based on the relationship between the compressive strength and the concentrations of Mg2+ and SO42- ions.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Mechanics of Materials
- Mechanical Engineering