【摘要】 将硼酸、葡萄糖酸钠和聚羧酸盐减水剂按一定比例复合,研制出一种用于硫铝酸盐水泥的新型缓凝减水剂M,实验表明,该外加剂对硫铝酸盐水泥具有较强的缓凝及减水作用。采用该外加剂和42.5级快硬硫铝酸盐水泥,配制出具有良好工作性的C50早强微膨胀钢管混凝土:初始坍落度为24 cm,3 h后仍达18 cm以上,不离析、不泌水,满足泵送施工要求;其3 d抗压强度达50 MPa以上6、0 d自由膨胀率3.41×10-4,能有效解决钢管混凝土中普遍存在的脱粘问题。更多还原

【Abstract】 A new type of high-effective retainers and water-reducer M for sulphoaluminate cement,of which main ingredients were borax,sodium gluconate and polycarboxylate water-reducer,was developed in this paper.By using M and the rapid-hardening sulphoaluminate cement（R.SAC）,pumped C50 steel tube-confined concrete was prepared.The workability and mechanical properties of this kind of steel tube-confined concrete were researched.Experimental results showed that the fresh C50 sulphoaluminate cement concrete had a perfect workability such as its slump was 23 cm and its flow was higher than 60 cm,which met the requirements of concrete pumping technique.The compressive strength for 3 d was above 50 MPa and the 28 d strength was 61.1 MPa,while the modulus for 28 d was 42.1 GPa.Furthermore,the free-expansion ratio for 60 d age was(3.41×10^-4),which could effectively decreased the problem of separation of the concrete and steel tube generally existed in steel tube-confined concrete.更多还原