C_(3)A含量对硅酸盐-硫铝酸盐复合体系水化及力学性能的影响  

Effect of C_(3)A content on hydration and mechanical properties of silicate-sulphoaluminate composite system

作　　者：李帅[1] 陈智丰 黄炳银 刘辉[1] 王剑锋[1] 无;LI Shuai(Faculty of Materials and Manufacturing,Beijing University of Technology,Beijing 100124,China)

机构地区：[1]北京工业大学材料与制造学部,北京100124 [2]唐山北极熊建材有限公司,河北唐山063705

出　　处：《水泥》2024年第8期80-86,共7页Cement

摘　　要：针对硫铝酸盐水泥(CSA)和硅酸盐水泥(PC)复配时存在凝结时间不易控制、强度发展不协调与后期体积不稳定等问题。为探究硅酸盐中铝相组成对PC-CSA复合体系水化的影响,通过外掺不同比例的C_(3)A单矿,研究了C_(3)A含量与硫铝比变化对PC-CSA复合体系体积稳定性和力学性能的影响及其作用机制。研究结果表明:随着C_(3)A含量的增加,PC-CSA凝结时间延长、力学强度降低及自由膨胀率增大。C_(3)A含量增加8%,PC-CSA体系初凝和终凝时间分别延长36 min、66 min,28 d抗压强度降低8.45 MPa,28 d自由膨胀率增加0.17%。C_(3)A和C_(4)A_(3)S存在竞争水化关系,C_(3)A含量会抑制C_(4)A_(3)S的水化,AFm含量增多,延缓C_(3)S的早期水化。体系水化产物AFt/C-S-H为0.15时,两者比例适中,AFt呈短粗棒状,强度高、体积稳定性好。Aiming at the problems of difficult control of setting time,uncoordinated development of strength and unstable volume in the later period when sulphoaluminate cement(CSA)and Portland cement(PC)are compounded.In order to explore the effect of aluminum phase composition in silicate on the hydration of PC-CSA composite system,the effects of C_(3)A content and sulfur-aluminum ratio on the volume stability and mechanical properties of PC-CSA composite system and its mechanism were studied by adding different proportions of C_(3)A single ore.The results show that with the increase of C_(3)A content,the setting time of PC-CSA increases,the mechanical strength decreases and the free expansion rate increases.When the content of C_(3)A increased by 8%,the initial setting time and final setting time of PC-CSA system were prolonged by 36 min and 66 min respectively,the compressive strength of 28 d decreased by 8.45 MPa,and the free expansion rate of 28 d increased by 0.17%.There is a competitive hydration relationship between C_(3)A and C_(4)A_(3)S.The content of C_(3)A will inhibit the hydration of C4A3S,increase the content of AFm,and delay the early hydration of C3S.When the hydration product AFt/C-S-H of the system is 0.15,the ratio of the two is moderate,and AFt is short and thick,with high strength and good volume stability.

关 键 词：硅酸盐-硫铝酸盐 铝酸三钙 水化 抗压强度 

分 类 号：TQ172.12[化学工程—水泥工业]