钛石膏掺量对碱激发胶凝材料强度与水稳定性的影响  

The effect of titanium gypsum content on the strength and water stability of alkali-activated cementitious materials

作　　者：李超宇 陈爱军 贾致荣[3] 石文彬 于滨 林雪峰 LI Chaoyu;CHEN Aijun;JIA Zhirong;SHI Wenbin;YU Bin;LIN Xuefeng(School of Transportation and Vehicle Engineering,Shandong University of Technology,Zibo 255049,China;Shandong Jiuqiang Group Company Limited,Zibo 255000,China;School of Architectural Engineering,Shandong University of Technology,Zibo 255049,China)

机构地区：[1]山东理工大学交通与车辆工程学院,山东淄博255049 [2]山东九强集团有限公司,山东淄博255000 [3]山东理工大学建筑工程学院,山东淄博255049

出　　处：《山东理工大学学报（自然科学版）》2022年第2期47-52,57,共7页Journal of Shandong University of Technology:Natural Science Edition

基　　金：山东省自然科学基金项目(ZR2020ME269)。

摘　　要：为了实现超硫钛石膏-粉煤灰胶凝材料在道路工程中的应用,需要研究高掺量钛石膏胶凝材料的水稳定性。设计了膏灰比为3∶7、4∶6、5∶5、6∶4、7∶3的5组配合比,制作试件240个,分别进行了标准养护及1 d、8 d或22 d浸水养护,测定了7 d、14 d、28 d无侧限抗压强度,计算了软化系数,并采用扫描电镜(SEM)和X射线衍射法(XRD)测试了材料的微观结构及化学成分。结果表明:钛石膏粉煤灰胶凝材料7 d强度增长缓慢,14~28 d强度增长显著,其中膏灰比为5∶5时,胶凝材料14 d、28 d龄期抗压强度值最大,分别为4.4 MPa、5.3 MPa;浸水养护8 d、22 d,胶凝材料膏灰比为5∶5的试件抗压强度最大,软化系数在0.82以上,因此膏灰比不宜超过5∶5;胶凝体系中水化产物主要为钙矾石(AFt)、水化硅酸钙(C-S-H)、水化硅铝酸钙(C-A-S-H),28 d水化产物随养护龄期增多,材料强度提高。In order to realize the application of super-sulfur titanium gypsum-fly ash cementitious material in road engineering,it is necessary to study the water stability of high-content titanium gypsum cementitious material.Five sets of mixture ratios of 3∶7,4∶6,5∶5,6∶4,7∶3 were designed,and 240 specimens were made,and they were subjected to standard maintenance and 1 d,8 d or 22 d immersion curing,followed by measuring the unconfined compressive strength of 7 d,14 d,28 d,calculating the softening coefficient,and analyzing the microstructure and chemical composition of the material by scanning electron microscope(SEM)and X-ray diffraction(XRD).The results show that the strength of the titanium gypsum fly ash cementitious material increases slowly at 7 d,but increases significantly from 14 d to 28 d.When the gypsum-to-ash ratio is 5∶5,the compressive strength values of the cementitious material at 14 d and 28 d are the largest,which is 4.4 MPa and 5.3 MPa,respectively.After immersing in water for 8 d and 22 d,the sample with gypsum-to-ash ratio of 5∶5 has the highest compressive strength,and the softening coefficient is above 0.82,so the gypsum-to-ash ratio should not exceed 5∶5.The main hydration products in the cementitious system are ettringite(AFt),hydrated calcium silicate(C-S-H),and hydrated calcium aluminosilicate(C-A-S-H).The 28 d hydration products increase with the curing age,and the strength is improved.

关 键 词：道路工程 碱激发胶凝材料 水稳定性 钛石膏 粉煤灰 

分 类 号：U414[交通运输工程—道路与铁道工程]