Microstructure and Strength Characteristics Analysis of Shrinkage-Compensating Shotcrete
Due to the easy cracking of shotcrete, shrinkage-compensating shotcrete is researched and its micro-structure and strength properties are analyzed. Firstly, cement slurry is made by CSA, accelerating agent and two different cements. When hydrated 3 days and 28 days , hydration products of cement slurry are analyzed by SEM and XRD in feature, crystal characteristics and mineral compositions. The compatibility of the two different cements and admixtures is studied in apparent characteristics, and the fact that Portland cement is more suitable for making shrinkage-compensating shotcrete is obtained. Then, mechanical properties of concrete which consists of Portland cement, expansive agent and steel fiber are did to analyze the influence of strength characteristics caused by mix amount of expansive agent and steel fiber. The results show that the compression strength and tensile strength of concrete improve with the increasing mix of steel fiber. Incorporation of the expansive agent is greater impact on concrete strength, when mix amount of expansive agent is 8%, strength properties are the best. When mix amount of steel fiber is 1.0% and expansive agent is 8%, the effect of cooperative enhancement is the best.
Jinglong Bu, Pengcheng Wang, Liqun Ai, Xiaoming Sang, Yungang Li
W. Huang and Q. Y. Ma, "Microstructure and Strength Characteristics Analysis of Shrinkage-Compensating Shotcrete", Advanced Materials Research, Vols. 287-290, pp. 1247-1251, 2011