Case Studies in Construction Materials (Dec 2024)

New insight on the thermal impact on cementitious materials due to high-temperature with water supply: Continuous expansive spalling in water

  • Taito Miura,
  • Shintaro Miyamoto,
  • Ippei Maruyama,
  • Abudushalamu Aili,
  • Takumi Sato,
  • Yuji Nagae,
  • Go Igarashi

Journal volume & issue
Vol. 21
p. e03571

Abstract

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In this study, the expansion behavior of cement materials after high-temperature heating and water immersion was observed experimentally. Two experiments were conducted using mortar specimens with different sand-to-cement ratios subjected to different high-temperature histories up to 1000 °C. In Case 1, the specimens were immersed in water after high-temperature heating and then cooled naturally; in Case 2, the specimens were immersed in water at high temperatures without the cooling process. Based on the results, it was confirmed that lime expansion due to the rehydration of CaO by heating occurred in Case 1. In contrast, dynamic continuous explosive spalling occurred in Case 2 because of water penetration into the specimen at a high temperature. The explosive spalling in water observed in Case 2 is a phenomenon that has not been reported to date. Possible failure mechanisms for lime expansion and continuous expansive spalling in water are suggested.

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