Mitigation of corrosion in carbonated concrete based on low-calcium silicate cement

A method of making a carbonated low calcium silicate cement-based material comprising:

• mixing a low calcium silicate cement with water, and filler particles comprising CaO or SiO2 having a particle size of 0.1 μm to 1000 μm, to form a wet mixture,
• casting the wet mixture in a mold, wherein the cast wet mixture has a plurality of pores that contain at least some of the water, wherein the water dissolves at least some elements from the low calcium silicate cement and/or the filler particles to produce a pore solution, wherein the pore solution in the cast wet mixture has a pH of 11.5 or greater;
• removing the cast wet mixture from the mold to obtain a porous body comprising pores containing the pore solution;
• and
• curing the porous body comprising pores containing the pore solution under the conditions of:
• a pressure from about atmospheric pressure to about 30 psi, a temperature in the range from about 30° C. to about 90° C., a relative humidity of about 10% to about 90%, an atmosphere of a CO2 gas concentration of about 15% to about 100%, and for a duration of about 8 hours to about 28 days, to form the low calcium silicate cement-based carbonated material comprising pores containing a modified pore solution, wherein the modified pore solution in the cured low calcium silicate cement-based carbonated composite material has a pH of at least 9.5.