CAJ | 학술논문

采用结晶水法测定掺加不同种类激发剂硬石膏的水化率以表征激发效果,并通过XRD和SEM对水化产物的相组成和形貌进行表征,优选出适合天然硬石膏基粉刷石膏的激发剂.在此基础上以天然硬石膏为基材制备出粉刷石膏,并对其工作性能、水化硬化性能等进行检测.结果表明,激发剂可显著改善硬石膏活性,不同种类和掺量影响差别较大.单掺5%煅烧明矾28 d水化率可达75%,单掺2%硫酸亚铁和2%草酸钠28 d水化率可达60%;复合激发剂激发效果优于单掺,28 d水化率超过85%;制备的硬石膏基粉刷石膏水化率大于等于80%、初凝时间为1~2 h、抗压强度超过20 MPa且无返霜现象,其他性能符合JC 517-2004.
채용결정수법측정참가불동충류격발제경석고적수화솔이표정격발효과,병통과XRD화SEM대수화산물적상조성화형모진행표정,우선출괄합천연경석고기분쇄석고적격발제.재차기출상이천연경석고위기재제비출분쇄석고,병대기공작성능、수화경화성능등진행검측.결과표명,격발제가현저개선경석고활성,불동충류화참량영향차별교대.단참5%단소명반28 d수화솔가체75%,단참2%류산아철화2%초산납28 d수화솔가체60%;복합격발제격발효과우우단참,28 d수화솔초과85%;제비적경석고기분쇄석고수화솔대우등우80%、초응시간위1~2 h、항압강도초과20 MPa차무반상현상,기타성능부합JC 517-2004.
This paper investigated the effects of activators’ category and dosage on hydration rate of natural anhydrite by testing the percentage composition of crystallization water. At the same time, the characterization of hydration products was carried out by means of X-ray diffraction (XRD) and scanning electron microscope (SEM). Then the gypsum plaster with natural anhydrite was produced and tested on the basis of the optimization activators. The results showed that the hydration activity of natural anhydrite could be improved observably with activators’ category and dosage. When the dosage of calcining alum is 5%, the hydration rate can reach 75%. When the dosage of ferrous sulfate or sodium oxalate is 2%, the hydration rate can reach 60%. The effect of compound activator is better than that of single activator, and the hydration rate can reach 85%. The properties of anhydrite-based gypsum plaster conform to the JC 517-2004, hydration rate no less than 80%, initial setting time in 1~2 h, compressive strength more than 20 MPa and no return cream phenomenon.