摘要
采用浸泡抗蚀性能试验方法(K法),对比研究了海工水泥和普通硅酸盐水泥的抗硫酸盐侵蚀性能。使用X射线衍射(XRD)、热重分析(TGA)、电子扫描(SEM)和电子计算机断层扫描(Computed to⁃mography,CT)分析了两种水泥硫酸盐侵蚀前后矿物成分和微观结构的变化,进行了机理分析。结果表明:海工水泥抗硫酸盐侵蚀性能优于普通硅酸盐水泥,海工水泥在3%硫酸钠溶液中浸泡11个月后侵蚀系数为1.03,而普通硅酸盐水泥为0.22。海工水泥主要水化产物为水化硅酸钙、钙矾石和较少的氢氧化钙,其在3%硫酸钠溶液中浸泡后生成微量二水石膏,不会对基体产生破坏。除水化硅酸钙和钙矾石外,普通硅酸盐水泥的水化产物中有较多的氢氧化钙和单硫型水化硫铝酸钙,其在3%硫酸钠溶液中会生成大量的二水石膏和钙矾石,两者的结晶膨胀会引起基体开裂。
The sulfate resistance of Portland cement used for ocean project(POP)and ordinary Portland cement(OPC)was studied by immersion corrosion resistance method(K method).X-ray diffraction(XRD),thermogravimetric analysis(TGA),scanning electron microscopy(SEM)and computed tomography(CT)were used to analyze the change of mineral composition and microstructure of the two kinds of cement before and after sulfate attack and the mechanisms were stud⁃ied.The results show that the sulfate resistance of POP is much better than OPC.The sulfate resistance coefficient of POP after exposed to 3%Na_(2)SO_(4) solution 11 months was 1.03 but the sulfate resistance coefficient of OPC was 0.22.The main hydration products of POP were hydrated calcium silicate,ettringite and less calcium hydroxide;a trace amount of gypsum was generated when POP was immersed into 3%Na_(2)SO_(4) solution without damaging the matrix.In addition to the hydrated calcium silicate and ettringite,there are more calcium hydroxide and monosulfate in the hydration products of OPC.When OPC was immersed into 3%Na_(2)SO_(4) solution,a lot of gypsum and ettringite were generated and both of their crystallization expansion will cause matrix cracking.
作者
刘浩然
周健
田稳苓
宋嵩
刘成健
张淑艳
LIU Haoran;ZHOU Jian;TIAN Wenling;SONG Song;LIU Chengjian;ZHANG Shuyan(School of Civil Engineering and Transportation,Hebei University of Technology,Tianjin 300401,China;Tangshan Polar Bear Building Materials Co.,Ltd.,Tangshan,Hebei 063705,China)
出处
《河北工业大学学报》
CAS
2022年第3期80-86,共7页
Journal of Hebei University of Technology
基金
国家自然科学基金(51702082)。
关键词
海工水泥
硫酸盐侵蚀
水化产物
微观结构
劣化机理
marine cement
sulfate attack
hydration products
microstructure
deterioration mechanism
