Results of Measuring the Thermal Concrete Properties by the Impulse Method

Abstract

The purpose of the study is to determine the thermo-physical characteristics of heavy concrete by pulse heating of different density samples by electromagnetic radiation with a flat temperature front with adjustable duration and duty cycle of the thermal pulse. It was proved, that heat conductivity and heat capacity of concrete essentially depend on humidity of concrete specimens, a distribution of components of cement stone filler, temperature and porosity of specimens. Specimens’ porosity was determined by value of maximum moisture content. It was found that all thermo physical characteristics increase nonlinearly with increasing moisture content, reaching saturation at maximum moisture content. The physical nature of the thermo physical properties is described in terms of the solid state model. An elastic porous, structure less model of concrete consisting of several phases is proposed. The authors of the work proposed a methodology for determining the thermo physical parameters of the components of heavy concrete and implemented on an experimental stand. The results of research on the test bench have shown that the values of characteristics increase nonlinearly with humidity. Authors proposed algorithm of determination of generalized thermo physical characteristics of heavy concrete taking into account its component composition.