Heating Rate Effect on Gas Permeability and Pore Structure of Mortar under High Temperature
Wei Chen,
Yuehan Liu,
Mingquan Sheng,
Hejun Zhang,
Yue Liang,
Frederic Skoczylas
Affiliations
Wei Chen
School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan 430068, China
Yuehan Liu
School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan 430068, China
Mingquan Sheng
School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan 430068, China
Hejun Zhang
School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan 430068, China
Yue Liang
School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan 430068, China
Frederic Skoczylas
CNRS (Centre National de la Recherche Scientifique), Centrale Lille, UMR9013—LaMcube—Laboratoire de Mécanique Multiphysique et Multiéchelle, Université de Lille, F-59000 Lille, France
This experimental study investigated the effect of heating rate on mortar gas permeability and microstructure. The mortar was heated to three target temperatures (400 °C, 500 °C, and 600 °C) at three heating rates (5 °C/min,10 °C/min, and 15 °C/min). The variations of gas permeability and porosity were measured simultaneously at different confining pressures, and the changes in mortar microstructure were analyzed by NMR and SEM techniques. The results show that the porosity and gas permeability increase with an increase in temperature and heating rate. The gas permeability and porosity continue to decrease as confinement is increased due to a reduction in the pore volume. The microstructure observed by SEM indicates that the high heating rate induces some microcracks at 500 °C and 600 °C. The fractal dimension based on NMR can quantitatively characterize the complexity of the mortar pore structure and shows a quadratic decreasing relationship with gas permeability and porosity.
