C55自密实微膨胀钢管混凝土制备研究  

Production Research of C55 Self-compacting Minute Expensive Concrete for Steel Tube

作　　者：李小花 Li Xiaohua(Tiezheng Test Inspection Technology Co.Ltd.,Jinan Shandong 250200,China)

机构地区：[1]铁正检测科技有限公司

出　　处：《铁道建筑技术》2019年第10期8-11,17,共5页Railway Construction Technology

基　　金：2017年山东省第二批技术创新项目(201720701018)

摘　　要：采用绝对体积法,以粗骨料体积、砂的体积分数、矿物掺合料比例为因素,利用K6(4^5)正交组合进行自密实混凝土配比计算,经试拌找到较理想的组合即粗骨料体积0.33、砂体积0.45、矿物掺合料配比30%。从提升配比强度、降低黏度,矿物掺合料影响、膨账剂对配比收缩率影响角度,对该组合进行优化。经具体试验确定粉煤灰掺量15%,取消矿粉,保持肢凝材料总量不变的情况下增加水泥掺量;掺加5%黏度改性材料调整拌合物性能;研究不同膨胀剂及掺量对混凝土强度及自收缩的影响,确定合适的膨胀剂种类及掺量。最终制备出力学及干缩性能满足规范要求的高强、高流态、微膨胀自密实混凝土。In consideration of the volume of coarse aggregate,volume fraction of sand and proportion of mineral admixtures,the proportion of self-compacting concrete was calculated by L16(4^5)orthogonal combination with the absolute volume method.After trial mixing,the ideal combination was found,namely coarse aggregate volume 0.33,sand volume 0.45,mineral admixture ratio 30%.The combination was optimized from the aspects of increasing the strength of the mix,reducing the viscosity,the influence of mineral admixtures and the effect of expansion agent on shrinkage ratio of concrete.The concrete test confirmed that the content of fly ash was 15%,the mineral powder was cancelled,the cement content was increased without changing the total amount of cementitious materials,and the viscosity of mixtures was adjusted by adding 5% viscosity modifier.The effects were studied on the strength and autogenous shrinkage of concrete with different expansive agents and their dosages,and the suitable expansive agents and their dosages were determined by the concrete test.Finally,the micro-expansion self-compacting concrete with high strength and high flow was prepared for the requirements of the relevant standard in mechanical and dryshrinkage properties.

关 键 词：自密实混凝土 绝对体积法 正交试验 降黏作用 混凝土收缩 

分 类 号：TU528[建筑科学—建筑技术科学]