This research shows the progress of geopolymer synthesis based on high calcium fly ash. In this study, the fly ash contents of 60, 65, and 70 percents by weight and sodium hydroxide solution concentrations of 8 to 12 M were used. Alkali activators for the geopolymer synthesis consisted of sodium silicate (Na2SiO3) and sodium hydroxide (NaOH) and the weight ratio of Na2SiO3 to NaOH were 0.50, 1.00, and 1.50. Drying shrinkage deformation of geopolymer paste was investigated by longitudinal measurement in a room temperature. Generally, the drying shrinkage behavior could be divided into three groups. The minimum drying shrinkage strain below 3,000 x 10-6 mm/mm was observed. The results indicated that an increase in the fly ash to alkali solution ratio and the decease of NaOH concentration significantly decreased the drying shrinkage strain. The optimum ratio of Na2SiO3 to NaOH was 1.0. The findings show that high calcium fly ash geopolymer binder could be used for alternative construction materials with low shrinkage strain.
In this work, the enhancement of thermal and sound insulation properties of cement composite roofing tile with nanocellulose coated pineapple fiber and modified waste tire rubber is studied. The composite was composed of bacterial nanocellose (BNC) coated pineapple fibers, modified rubber particles, platicizer and type I Portland cement in the weight ratio of 10:50:0.8:100 with the water to cement ratio (w/c) of 0.5. The thermal conducitity of the fiber rubber cement composite could be reduced to 0.1080 ± 0.0048 W/m.K as opposed to 0.3810 ± 0.0041 and 0.5860 ± 0.0050 W/m.K for the fiber cement and the rubber cement composites, respectively. Moreover, the noise reduction coefficient of the fiber rubber cement composite could be increased to 0.2832 as opposed to 0.2143 and 0.1899 for the fiber cement and the rubber cement composites, respectively. These results revealed that adding nanocellulose coated pineapple fiber and modified rubber particles together to the cement composite can enhance the thermal insulation and sound absorption abilities of the composite roof tile significantly better than adding each constituent separately.
The use of kaolinitic clay, which chemical compound consists of mainly silica (SiO2) and alumina (Al2O3), mixing with charred seashells, consisting of mainly calcium oxide (CaO), could be improved by polymerization process. The ratio of kaolinitic clay and charred seashells used in the study ranges from 1: 0.6 to 1: 1.6 by weight. After curing for 28 days, the improved material has the ultimate compressive strength in the range of 3.7 to 7.9 MPa. In additions, the improved material has good heat resistance property. The utilization of natural waste materials together with polymerization technique could improve the material properties to meet the demand of construction industry in the future.
This study compares the effects of rubber tire waste and rubber band waste on physical, mechanical, and thermal properties of cement composite for roofing application. The rubber particles, prepared from waste rubber tire (RT) and/or calcium carbonate filled rubber band (RB), were mixed with cement paste and tested for workability and flexural strength. It was found that RT yields higher workability than RB when mixed with the cement paste. The rubber-cement composites (CR) with the combination of RT and RB at the RT:RB volume fraction of 1.00:0.00 (CRT), 0.75:0.25 (CRT.75/B.25) and 0.50:0.50 (CRT.50/B.50) have sufficient workability and flexural strength. When mixing different rubber particles with oil palm fibers and the cement paste to obtain CFRT, CFRT.75/B.25, CFRT.50/B.50 rubber-fiber-cement composites, the composites with higher RT content have higher flexural strength, while those with higher RB content have lower thermal conductivity, implying better thermal insulation property. More importantly, all three types of rubber-fiber-cement composites yield excellent thermal insulation property, and meet the flexural strength required by the industrial standard for the fiber-cement roof tile sheets. The results suggest that the waste rubber-waste oil palm fiber-cement composites can be viable candidates for roofing application with promising potential for energy saving.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.