Preparation and experimental study on the thermal characteristics of lightweight prefabricated nano-silica aerogel foam concrete wallboards

• Published in: Construction & building materials Vol. 272; p. 121895
• Main Authors: Liu, Peng, Gong, Yan Feng, Tian, Guo Hua, Miao, Zheng Kun
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 22.02.2021
• Subjects: Experimental study; Fabricated wallboard; Foam concrete; Nano-silica aerogel; Thermal characteristics; Nano-silica aerogel; Thermal characteristics; Foam concrete; Experimental study; Fabricated wallboard
• ISSN: 0950-0618; 1879-0526
• DOI: 10.1016/j.conbuildmat.2020.121895

•A novel type of lightweight foam concrete was prepared by adding nano-silica aerogel, fiber and ceramist.•A prefabricated foamed concrete wallboard meeting the thermal performance requirement of 65% energy saving of residential building structure in the cold region (B region) of China was developed.•The thermal characteristics of the wallboard were tested under steady-state and unsteady-state conditions. The optimal mix ratio of nano-silica aerogel foam concrete was determined through preliminary design and orthogonal experiment optimization. Based on the design of the size, reinforcement, and interface form of the prefabricated wallboard, a prefabricated foam concrete wallboard which met the requirements for use in the cold region (B region) of China was developed. The dry bulk density, thermal conductivity, compressive strength, and porosity were tested respectively. Besides, the microscopic characteristics of the foam concrete were tested through scanning electron microscopy(SEM). The thermal characteristics of the wallboard were tested under steady-state and unsteady-state conditions. The heat transfer coefficient is 0.5518 W/(m2·K) under steady-state conditions. The test results are that the temperature amplitudes of the inside and outside wall surfaces are 5.2℃ and 0.054℃ respectively, the temperature attenuation multiple and attenuation coefficient are 96.3, 0.0104, The delay time of the wall surface is up to 11.8 h, the heat storage coefficient of the surface is 2.48 W/(m2·K), thermal inertia index is 4.15, tested by using self-designed test device, and the periodic variation of sol–air temperature of Xuzhou area in summer is taken as boundary conditions. It shows that the developed wallboards have good thermal characteristics.