Thermal Effect on the Failure of Cement Hydration Products Under High Velocity Flow Cavitation
HE Yang1,2, QIAN Wenxun1,2, ZHANG Yanchi1,2, CAI Yuebo1,2, WANG Xin1,2
1 Nanjing Hydraulic Research Institute, Nanjing 210029; 2 Research Center on New Materials in Hydraulic Structures, Ministry of Water Resources, Nanjing 210029
Abstract: With the development of dam construction skills and further utilization of water power resources, the construction of high dams improves rapidly. It leads to a major problem of protection against the cavitation erosion caused by high velocity and large flow of flood discharge. Instead of the conventional way of mechanical analysis on cavitation, this paper was devoted to illustrate the thermal impact on the kind of erosion. Ultrasonic cavitation device was utilized for the test of various kinds of cement paste, with a combination analysis of erosion surface of hardened cement paste and micro-analysis of hydration product, the article studied the thermal effect of cavitation on the surface of hardened cement paste. The thermal effect of cavitation erosion on cement hydration products was initially discussed in this paper. Results indicated that cavitation erosion on cement paste is not only a simply mechanical failure but also conducts a thermal decomposition on hydration of cement, which could cause the partial decomposition of cement hydration products. To be specific, the mass loss of hydration gel substances is no less than 40% so as the loss of hydrated lime is more than 25% during a 6 hours ultrasonic cavitation experiment. In that way, the considerable hydration mass loss could lead to a significant impact on cement paste deterioration.
何旸, 钱文勋, 张燕迟, 蔡跃波, 王新. 高速水流下空蚀热效应对水泥水化产物的破坏[J]. 材料导报, 2018, 32(24): 4281-4285.
HE Yang, QIAN Wenxun, ZHANG Yanchi, CAI Yuebo, WANG Xin. Thermal Effect on the Failure of Cement Hydration Products Under High Velocity Flow Cavitation. Materials Reports, 2018, 32(24): 4281-4285.
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2018, Vol. 32 
