轻质相变混凝土的研发及物理力学性能实验研究.

Using silica aerogels as the matrix material and low-temperature phase change paraffin wax as the phase change material, shaped composite phase change materials were prepared. Characterization and stability tests of the shaped composite phase change materials were conducted using Fourier-transform infrared spectroscopy, differential scanning calorimetry, synchronous thermal analysis, and diffusion-permeation circle tests. The results indicate that the shaped composite phase change material prepared with a wax adsorption mass of 75% is the most stable, with the interaction between silica aerogels and paraffin wax being purely physical adsorption. The phase transition temperature of the shaped composite phase change material is 26.52 °C, and the latent heat of phase transition is 56.2 J/g» By incorporating it into EPS concrete, the cement paste flowability experiment restricts the optimum proportion of shaped composite phase change material to around 16%, yielding optimal working performance of the concrete mixture. Physical-mechanical property tests reveal that with the addition of the shaped composite phase change material, the compressive, flexural, and splitting tensile strengths of the specimens all exhibit a certain degree of improvement. Through thermal storage performance tests in a thermal chamber, specimens with added shaped composite phase change material show a decrease in the slope and peak value of the heating and cooling curves. This indicates that lightweight phase change concrete has excellent temperature control performance and can be used in energy-efficient building envelope systems. [ABSTRACT FROM AUTHOR]