Strength and Microstructure of Mortar Containing Glass Powder and/or Glass Aggregate

The compressive strength of mortar containing glass powder（GP） and/or glass aggregate（GA） was tested, and its microstructure was also studied by thermogravimetric and differential thermal analysis（TG-DTA）, scanning electron microscopy（SEM）, energy dispersive spectroscopic analysis（EDX）, and X-ray diffraction（XRD） techniques. The incorporation of GA would decrease the compressive strength of the mortar in the absence of GP. Incorporating both GA and GP could change the hydration environment, promote pozzolanic reaction of GP and improve the compressive strength. GP does not lead to but can effectively control ASR（Alkali Silica Reaction）. GP and GA do not transform the type of hydrates, but have a great influence on the amounts of hydration products, and generate more calcium silicate hydrate（C-S-H gel） with lower Ca/Si ratio. GP and GA with good gradation will make the microstructure denser.

Experimental study and assessment of thermal energy storage mortar with paraffin/recycled brick powder composite phase change materials

Thermal energy storage recycled powder mortar(TESRM)was developed in this study by incorporating paraffin/recycled brick powder(paraffin/BP)composite phase change materials(PCM).Fourier transform infrared and thermogravimetric analysis results showed that paraffin/BP composite PCM had good chemical and thermal stability.The onset melting temperature and latent heat of the composite PCM were 46.49°C and 30.1 J·g−1.The fresh mortar properties and hardened properties were also investigated in this study.Paraffin/BP composite PCM with replacement ratio of 0%,10%,20%,and 30%by weight of cement were studied.The results showed that the static and dynamic yield stresses of TESRM were 699.4%and 172.9%higher than those of normal mortar,respectively.The addition of paraffin/BP composite PCM had a positive impact on the mechanical properties of mortar at later ages,and could also reduce the dry shrinkage of mortar.The dry shrinkage of TESRM had a maximum reduction about 26.15%at 120 d.The thermal properties of TESRM were better than those of normal mortar.The thermal conductivity of TESRM was 36.3%less than that of normal mortar and the heating test results showed that TESRM had good thermal energy storage performance.