硫酸盐/氯盐侵蚀下水泥胶砂力学性能研究

Study on Mechanical Properties of Cement Mortar under Sulfate/Chloride Erosion

盐侵蚀对水泥混凝土的劣化作用主要表现为对水泥胶砂的劣化。采用标准ISO抗折强度和抗压强度试验研究不同浓度复合硫酸盐/氯盐侵蚀条件下,水泥胶砂浸泡不同周期的抗折强度和抗压强度;进一步分析水泥胶砂在不同浓度复合硫酸盐/氯盐侵蚀下力学性能的变化规律,并探讨盐蚀条件下水泥胶砂性能劣化机理。结果表明:在复合硫酸盐/氯盐侵蚀下,水泥胶砂力学性能发生不同程度劣化;随着硫酸盐浓度增加,劣化效果越明显,随着氯盐浓度增加,劣化效果有所减弱;盐溶液渗入水泥胶砂孔隙中发生化学侵蚀是导致水泥砂浆性能劣化的主要原因,而氯盐能一定程度上抑制硫酸盐的侵蚀。研究成果可为复合盐侵蚀地区抗侵蚀提供一定的基础。

The deterioration of cement concrete by salt erosion mainly manifests the deterioration of cement mortar.The standard ISO flexural strength and compressive strength tests were used to study the flexural strength and compressive strength of cement mortar in different cycles under different concentrations of composite sulfate/chloride erosion.Furthermore,the change of mechanical properties of cement mortar under different concentrations of composite sulfate/chloride erosion is analyzed,and the mechanism of cement mortar performance degradation under salt erosion conditions is discussed.The results show that the mechanical properties of cement mortar deteriorate to varying degrees under the combined sulfate/chloride erosion.As the sulfate concentration increases,the degradation effect becomes more obvious,and as the chloride concentration increases,the degradation effect decreases.Chemical erosion caused by the infiltration of salt solution into the pores of cement mortar is the main reason for the deterioration of the performance of cement mortar,and chloride salt can inhibit the sulfate erosion to a certain extent.The research results can provide a certain basis for anti-erosion in composite salt erosion areas.