SAC和P.O改性复合胶凝材料的配比试验研究

Experiential study on the proportion of SAC and P.O modified composite cementitious materials

在富水情况下传统的普通硅酸盐水泥基注浆材料难以满足工程要求。以硫铝酸盐水泥与普通硅酸盐水泥作为复合胶凝材料,通过粘结剂(HPMC)对其改性,并以流动度、凝结时间、抗水分散性和强度等指标进行最优配比试验,结果表明:SAC和P.O改性复合胶凝材料凝结时间较短;随着HPMC掺量的增加,材料抗水分散性逐渐提高、强度逐渐下降;同时当水灰比大于0.5时,材料的抗水分散性开始降低。通过工程应用验证,该改性速凝抗水分散型注浆材料最佳配比为P.O 42.5与SAC比例6:4、水灰比0.45、HPMC掺量为胶凝材料质量的0.15%。

In the case water-rich conditions,the traditional Portland cement based grouting material is hardly meeting the engineering requirements.Sulphoaluminate cement and Portland cement are used as composite cementitious materials,modified by binder(HPMC)AND.The optimal proportion tests are carried out with indexes of fluidity,setting time,water dispersibility and strength.The results show that the setting time of SAC and P.O modified composite cementitious material is short and the water dispersibility increases;as the HPMC content increases,the strength decreases.At the same time,while the water-cement ratio is greater than 0.5,the water dispersibility of the material begins to decrease.It is verified by engineering application that the best proportion of the modified quick-setting and water-resistant dispersive grouting material is that the ratio of P.O42.5 to SAC is 6:4,the ratio of water to cement is 0.45,and the content of HPMC is 0.15%of the mass of the cementitious material.