Inhibiting Effect of Admixtures on TSA of Concrete
YANG Chang hui,BAN Ke cheng and LIU Ben wan
DOI:10.11835/j.issn.1674-4764.2011.02.025
Received December 08, 2010,Revised , Accepted , Available online July 01, 2015
Volume ,2011,Pages 126-131
- Abstract
The cement paste added with chemical admixtures is kept out (5±2)℃, 5% in mass MgSO4 corrosion solution in 300 d of immersion. Its visual appearance, compressive strength and erosion products are studied. Its erosion products are analyzed by the way of X ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). It shows that the calcium formate can delay the TSA of harden cement paste to occur, but can not stop the development of TSA. The resistance of mortar to TSA increases with the raise of calcium formate in the range of 03% to 07%. The reason why barium nitrate can inhibit the formation of thaumasite is that it can combine with SO2-4 which is essential for the forming of thaumasite. Thus, the TSA of mortar is reduced in degree. The harden cement paste shows good resistance to TSA when barium nitrate is approximately 1% of cement.