Damage Mechanism of Portland Cement Paste partially Immersed in Na2SO4 Solution without Carbonization
In a constant temperature (20±1℃) and constant humidity (80±5%) environment with carbon dioxide insulation, the cement paste specimens with different water-cement ratios were partially immersed in a 5% sodium sulfate solution.In the erosion experiment, the destruction of the specimen was observed, and the erosion product was microscopically analyzed by XRD and TG, The results show that under the condition of avoiding carbonization, the salt-crystallization damage of the Portland cement paste half-soaked in sodium sulfate solution does not occur, and only chemical reactions generate a large number of swelling products such as ettringite and gypsum.Its damage mechanism is chemical erosion.After immersed for 100 days, under the effect of the wick action, the amount of chemical products such as ettringite and gypsum produced in the water evaporation zone of the test piece were much more than the immersion zone, and the chemical damage there was more serious.
Chemical sulfate attack Portland cement Na2SO4 carbonization salt crystallization
Z.Q.Liu M.Pei D.H.Deng F.Y.Zhang
Central South University, Changsha, China
国际会议
福州
英文
551-558
2018-11-04(万方平台首次上网日期,不代表论文的发表时间)