硅酸盐学报2019，Vol.47Issue(8)：1123-1136,14.DOI:10.14062/j.issn.0454-5648.2019.08.14
Mg2+-SO42——Cl-侵蚀衬砌喷射混凝土耐久性能退化机理
Durability Degradation of Lining Shotcrete Exposed to Mg2+-SO42——Cl-
摘要
Abstract
Saline soil is widely distributed in the Northwestern China and has high concentrations of Mg2+,SO42-,and Cl-,which cause a lining shotcrete durability to degrade rapidly.The lining shotcrete durability in saline soil environment was investigated by a dry-wet cycle method.The dynamic elastic modulus,mass,and compressive strength were measured in shotcrete submerged in 10％Na2SO4 (solution) and 5％Na2SO4+5％MgSO4+3.5％NaCl (solution Ⅱ).The durability degradation mechanism was investigated via the analysis of mineral composition,corrosion products,content of water-and acid-soluble ion,and pH value.The corrosion process of shotcrete exposed to solution Ⅰ is ettringite corrosion,ettringite and gypsum combined corrosion,and gypsum corrosion.Shotcrete exposed to solution Ⅱ is divided into three stages,i.e.,brucite,gypsum and ettringite formation,C-S-H decomposition and thaumasite formation,and M-S-H formation.Shotcrete exposed to solution Ⅱ has higher Ca2+ content and pH value but a lower SO42-content than shotcrete exposed to solution Ⅰ.The physical and mechanical properties and the damage depth of shotcrete exposed to solution Ⅱ are greater than those of shotcrete exposed to solution Ⅰ.关键词
喷射混凝土/耐久性/硫酸钠侵蚀/硫酸镁-硫酸钠-氯化钠侵蚀/侵蚀机理Key words
shotcrete/durability/sodium sulfate corrosion/magnesium sulfate-sodium sulfate-sodium chloride corrosion/corrosion mechanism分类
建筑与水利引用本文复制引用
王家滨,牛荻涛..Mg2+-SO42——Cl-侵蚀衬砌喷射混凝土耐久性能退化机理[J].硅酸盐学报,2019,47(8):1123-1136,14.基金项目
国家自然科学基金重大项目支课题(51590914) （51590914）
陕西省自然科学基金(2018JQ5032) （2018JQ5032）
陕西省教育厅自然科学研究专项(18JK0376),西安工业大学校长基金(XAGDXJJ17019. （18JK0376）
