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The aim of this work was to study the feasibility of using basalt fibers as the reinforcement phase in fiber-cement products which was the fiber-reinforced construction materials used for roof, wall, ceiling, and floor applications. The feasibility study included (1) the alkaline resistant test of the basalt fibers by soaking the basalt fibers in 1 N Ca(OH)2 up to 28 days, and (2) the mechanical test based on ASTM C1185 standard on the fiber-cement board that used basalt fibers as a reinforcement phase. Scanning electron microscope (SEM) and x-ray diffractometer (XRD) were used to characterize the basalt fibers after alkaline resistant test. The basalt-fiber reinforced cement board was produced on the industrial level by using Hatschek process.From the alkaline resistant test, basalt fibers had well alkaline resistant. From the mechanical test, the modulus of rupture (MOR) of basalt-fiber reinforced cement boards passed the requirement of TIS 1427-2540 and ASTM C1186 standard. Therefore, basalt fibers could be considered as a good candidate for using as a reinforcement phase in the fiber-cement products.

The aim of this work was to reduce the water absorption of the fiber-cement composites, which is also known as fiber-cement products, by the crystal modification of cement matrix using the additives including polyurethane-based corn starch–lithium perchlorate (LiClO4), and acrylic resin emulsion-based chitosan-silicate hybrid compound. To prepare the samples, the mixtures consisting Portland cement Type I, sand, cellulose fibers from pine trees, gypsum, and additive were mixed with water. The percentages of additive in the mixtures before mixing with water were 0.03 to 0.17 wt%. The green sheets of samples were formed by filter-pressing method, air cured for 1 day, and then autoclaved at 8 bars and 140°C for 12 h. The experimental results indicated that the water absorption of the samples was reduced when polyurethane-based corn starch–lithium perchlorate (LiClO4) was used as the additive due to the crystallization of the small crystals within cement matrix, while their mechanical properties including modulus of rupture (MOR) and modulus of elasticity (MOE) of the samples using this additive conform industrial standard.

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The purpose of this work was to study the microstructure and the mechanical properties of the fiber-reinforced cement composites that used the nucleating-agent activated coal-fired power plant bottom ash as a raw material in the mixture for producing the composites. The raw materials for producing the fiber reinforced cement composites were the ordinary Portland cement (OPC), natural gypsum, cellulose fiber, and bottom ash. The bottom ash was chemically treated by the nucleating agent, a chemical that was prepared by the precipitation process from the aqueous solutions of sodium silicate (Na2SiO3) and calcium nitrate (Ca (NO3)2). To prepare the samples, the mixture consisting of 34.75 wt% OPC, 34.75 wt% bottom ash, 25 wt% natural gypsum, and 5.5 wt% cellulose fiber was mixed with the nucleating agent at the amount of 0 to 4.5 % of OPC weight in the mixture, and water to form the slurry. Then, the samples were produced by filter pressing process and cured in the autoclave for 16 hrs at 180 °C, and 10 bars. The mechanical properties of the samples including modulus of rupture (MOR), modulus of elasticity (MOE), and toughness were characterized by the universal testing machine (UTM). The microstructures of the samples were observed by scanning electron microscope (SEM). The results showed that the utilization of nucleating agent affect the microstructure of the sample leading to the improvement in the mechanical properties of samples.