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A challenge for environmental conservation will be the manufacturing of composite materials using by-products/waste from the agricultural sector. This study focuses on composites that were made by utilizing an epoxy resin matrix and reinforcement made from crushed sunflower seed husk (SSH). The composites are manufactured by compression moulding technique by varying the filler volume fraction from 5 to 50%. The tensile test, impact test, and hardness test of the composites are carried out based on ASTM standards. According to the findings, the SSH filler-epoxy composite exhibits better in impact test values, whereas increasing the volume percentage tends to decrease the tensile and hardness values. Furthermore, the experimental tensile strength is compared with the theoretical model. [ABSTRACT FROM AUTHOR]

A study was carried out at the Department of Vegetable Science, Horticultural College and Research Institute, Periyakulam, during 2019-20 to assess the genetic variability, heritability and genetic advance of important quantitative and qualitative traits in fifty-two perennial moringa genotypes. Analysis of variance revealed a significant differences for all traits. High genotypic and phenotypic coefficients of variation were noticed for pod yield, the number of pods per tree, total carotenoids, iron and pod weight indicating maximum variability among the different genotypes. High estimates of heritability coupled with high genetic advance obtained for all the traits except crude fibre content indicating the presence of additive gene effect which showed the effectiveness of selection for these traits. Presence of high heritability coupled with moderate genetic advance for crude fibre content revealed that the straight selection has a limited scope for further improvement of the trait. Among fifty two genotypes PKM MO-55 has the highest iron content (7.20mg/100g), number of pods/tree (306.50) and pod yield (36.47 kg/tree). [ABSTRACT FROM AUTHOR]

The article presents a study on the practical applications of geopolymers presented at the 31st International Conference on Advanced Ceramics and Composites. The study showed that geopolymers can be used for multiple applications including fire-resistant films for modular housing, hydrothermal corrosion-resistant films and high-temperature light-weight aircraft coatings. The use of geopolymerized fly ash to replace Portland cement for concrete applications is also tackled.

Geopolymer materials have been proposed for various applications due to their excellent fire resistance and low processing cost. One requirement that geopolymer composites need to meet for structural applications is graceful failure, as catastrophic failure during service can result in significant loss of life. In this paper, the properties of novel low cost composites made by infiltrating stainless steel mesh with geopolymer resin are reported. Four point flexure tests on these composites showed metal-like yielding behavior instead of catastrophic failure and the “yield strength” was significantly higher than the flexure strength of the geopolymer matrix. Exposure to high temperatures, 800 and 1,050°C, resulted in the “yield strength” decreasing to ∼59 and ∼44% level respectively compared to the strength of as-processed samples. However, the good ductility was still retained after the high temperature treatment, which makes this novel composite a strong candidate for the applications where catastrophic failure upon fire/high temperature exposure needs to be avoided. [ABSTRACT FROM AUTHOR]

The study presented in this paper deals with the fire performance of balsa sandwich panels made using inorganic Geopolymer resin and high-strength fiber facings. A thin layer of a fire-resistant paste composed of Geopolymer and hollow glass microspheres was applied to the facings to serve as a protective fire barrier and to improve the fire resistance of the sandwich panels. Using 17 sandwich panel specimens, the primary objective of this program was to establish the minimum amount of fireproofing necessary to satisfy the Federal Aviation Administration (FAA) requirements for heat and smoke release. The influence of this fireproofing insulation on the increase in mass of the panels was also evaluated. The system is simple and inexpensive to manufacture, and a 1.8-mm-thick layer of fireproofing satisfies the FAA requirements for both heat release and smoke emission. [ABSTRACT FROM AUTHOR]

The objective of this paper is to study the fatigue performance of concrete beams strengthened with carbon fiber sheets bonded by an inorganic matrix. Large size reinforced concrete (RC) beams were strengthened with three layers of carbon fiber sheets and tested under fatigue loading. The relationship between fatigue strength, crack width, and number of cycles was studied and analyzed. Results showed that both load capacity and number of cycles of the RC beams were significantly increased with carbon fiber sheets. The fatigue strength increased by as much as 55% as compared with that of the control beams. Fatigue failure of the RC beams strengthened with carbon fiber sheets bonded with an inorganic matrix started with steel rupturing followed by fiber rupture. It was observed that the fatigue cracks developed during the first few cycles. With increasing number of cycles, the crack width and crack depth increased during the first half million cycles of loading, and thereafter the crack width and depth tended to stabilize. [ABSTRACT FROM AUTHOR]

Deals with high fiber volume fraction high-performance cement composites under compressive and flexural strength. Fiber volume fraction; Modulus of rupture; Mixing and casting of specimens; Properties of mortar and concrete mixture proportions at time of placement.

Presents a study which examined the performance of inorganic and organic matrix when used to externally strengthen reinforced concrete beams with carbon fiber sheets. Properties of inorganic matrix; Overview of the experimental program; Results and discussion.

Examines the performance of concrete columns wrapped with carbon and glass fiber-reinforced polymer composite (FRPC) sheets subjected to wet-dry and freeze-thaw conditions. Details of specimen; Specimen preparation; Effect of confinement on virgin specimens; Effect of exposure; Effect of exposure on ductility.

The results of an experimental investigation on the freeze-thaw durability of fiber reinforced concrete is presented. The primary objective of the research program was to determine whether the air content is the most significant parameter for the freeze-thaw resistance of fiber reinforced concrete, as is the case with normal concrete. Accordingly, air content in the mixtures was varied from 1.2 percent to /0.8 percent. The results indicate that air content is the most significant factor. Based on the results, it is recommended that at least 8.0 percent air content should be specified for concrete structures exposed to severe freeze-thaw loading. Comparison of fiber reinforced concrete specimens with plain concrete specimens indicates that their behavior under freeze-thaw loading is essentially similar. For the same air content, freeze-thaw durability is the same for both plain and fiber reinforced concrete. An increase of cement content and a reduction of water-cement ratio improves the durability. The results also indicate that the toughness index of fiber reinforced concrete does not change appreciably with freezing and thawing, provided the mixture is designed to prevent deterioration by incorporating sufficient air. [ABSTRACT FROM AUTHOR]