| 摘要 |
FIELD: physics. ^ SUBSTANCE: heat current is applied onto the surface of a test specimen and temperature drop is measured on the surface of the test specimen. For each test specimen, percentage content of main chemical elements of Portland cement SiO2, AI2O3, Fe2O3, CaO, is determined, and the pore volume VB is determined for foamed concrete. The coefficient of effective thermal conductivity of the foamed concrete is then calculated using the formula: ef=((4.2SiO2-15.45Al2O3-7.95Fe2O3+1.06CaO)/100)(1-VB)+(0.024+5.25d)VB, where ef is the coefficient of effective thermal conductivity of foamed concrete, W/(mK); SiO2 is the percentage content of silicon dioxide, %; Al2O3 is the percentage content of aluminium oxide, %; Fe2O3 is the percentage content of iron oxide, %; CaO is the percentage content of calcium oxide, %; VB is the volume pores in the foamed concrete, conducting the heat current; d is the average diametre of pores in the structure of the foamed concrete. ^ EFFECT: simpler method of determining the coefficient of effective thermal conductivity of foamed concrete. ^ 2 tbl |
