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Hybridized sheet molding compound (hybrid SMC) with pre-impregnated glass fiber fabric (F-SMC) was identified as a promising solution for applying on the subcomponents of the battery casing based on numerical structural analysis. A lower part weight and cost with fewer assembly processes than the state-of-the-art technology made of aluminum were shown. To further evaluate the manufacturing feasibility of co-molding F-SMC with basic SMC and the resulting hybridization effect on the mechanical properties, the study below has been conducted. The manufacturing feasibility was investigated at an 1800-ton hydraulic press at AZL. Two different F-SMCs with varied weft and warp ratios and different laminate architectures (sandwich structure and one-sided) were considered on a 3D tray-based part, similar to a battery tray. For the variant, F-SMC on one side, it is easy to be over-molded by the basic SMC using the standard compression process parameters. For the sandwich structure, the cavity between the F-SMCs can also be filled. Both layouts present an excellent interface without any significant air voids investigated by optical microscopy. In addition, the mechanical properties were studied under the uniaxial transverse loading on one homemade test cell. Compared with the F-SMC on one side under compression stress, the sandwich structures provide a much more significant reinforcing effect with an average increase in the flexural modulus, flexural strength, and absorbed energy at target deformation by 61.3 %, 78.2 %, and 88.4 %, respectively. The failure modes were microscopically investigated and determined. After the lifetime, the components can be easily recycled with the hybrid SMC's consistent resin and fiber type. [ABSTRACT FROM AUTHOR]

A fatigue mechanism that develops over time frequently results in an in-situ fracture of the denture base. Fracture occurs as a result of the microscopic cracks that develop over time. For appreciate the effect of two various surface treatments, Ethyl acetate and Methylene chloride and repaired acrylic resin reinforced with varying amounts of aluminum oxide (Al2O3) on the flexural strength of repaired denture base. For flexural strength, (90) samples of heat-polymerized resin were sized in accordance with the American Dental Association specification no. 12 (65 mm 10 mm 2.5 mm) length, width, and thickness. (10) control group without any addition, 80 specimens were distributed into two main groups according to repair surface treatment: with methylene chloride and with ethyl acetate, these two groups are sub divided in to four sub groups according to the percentages of Al2O3 nanoparticles addition that is, (0.25%,0.5%,0.75%, 1%). were fund to auto polymerizing polymer resin which was used as repaired material. Flexural strength of the repair acrylic was dramatically increased (P< 0.05) by the addition of nano-Al2O3. The pre-surface ethyl acetate treatment and reinforcement with 0.25% nano-Al2O3 had the highest value (71.22±7.17), whereas the lowest value was found in the pre surface treatment with methylene chloride reinforced with 1% nano-Al2O3 (52.85±3.25). The flexural strength of restored denture bases was increased by adding nano-Al2O3 to the pre-surface treatment repair resin, however it was diminished by high concentrations. [ABSTRACT FROM AUTHOR]

Flexural strength evaluation of betel leaf fiber and cassia filler reinforced epoxy composites and comparison with betel leaf fiber reinforced epoxy composites. As a test group, betel leaf fibers and novel Cassia fillers were formed with 10% to 20% by volume epoxy composites (N=40). The betel leaf fiber epoxy resin composite without filler was used as the control group (N=20). The composite samples were prepared by hand lay-up method. Flexural tests were performed on epoxy composites containing the novel Cassia filler and unfilled at 10% and 20% by volume. The maximum flexural strength of the sheet-like fiber-reinforced areca nut-epoxy composite was 33.15 MPa, with statistically significant values of 33.11 MPa and 33.41 MPa for the 10% and 20% filler-reinforced composites, respectively (p=0.000; p<0.05) observed. Within the limits of this study, the bending of the betel leaf fibers of Cassia cassia foliage with a volume fraction of 20% compared slightly improved strength. [ABSTRACT FROM AUTHOR]

This research presents a practical study on the use of steel plates to increase efficiency based on gluing these with epoxy to the tensile face of an inverted T-beam flange in order to increase the strength of reinforced concrete (RC) beam specimens. Examining the design and construction stages, as well as behaviours under earthquake and increasing load conditions showed a decrease in the flexural strength of standard beams that must be avoided by strengthening with steel plates. The practical experimental investigation thus included six simply supported RC inverted T beams. One beam acted as a control beam specimen, without any strengthening, while the other beam specimens were strengthened with steel plates of various lengths and widths to obtain data on the flexural strength of the inverted T beam at the lowest possible cost to gain the best results in terms of efficiency, performance and strength of specimens. Applying the load during the test of these specimens was on all specimens until failure. The failure of strengthened RC beam specimens was assessed by means of ductile behavior, and the test results showed that the steel plate strengthened beams offered significant improvement in terms of increased ultimate load capacity as compared with the control beam specimen, as well as offering higher first cracking load and deflection values. [ABSTRACT FROM AUTHOR]

Using recycled aggregate (RA) instead of natural aggregate (NA) is one of the most sustainable choices in concrete construction in terms of decreasing the consumption of natural aggregates, reducing the landfill area, and improving the environment. However, being possesses relatively more defects compared to natural aggregates (NA), RA concrete is found to be generally associated with poor performance in terms of its mechanical performance as well as cracking behaviour. Accordingly, it is essential to implement strategies that can enhance the RA performance. For this to be tackled, a number of strategies and procedures have been proposed in numerous research works. In this regard, steel fibers, up to a certain limit, have been found to have a positive impact on RA-based concrete. The aim of the present paper is to conduct a critical review regarding the fresh and hardened properties of fiber reinforced RA-based concrete (SFRAC). The study has shown a light on the microstructure of RA and material characteristics of SFRAC. It also emphasizes the influences of steel fibers on the fresh properties, compressive strength, splitting tensile strength, and flexural strength of RA concrete mixes. The investigated properties will be discussed in terms of maximum replacement ratio, SF type and aspect ratio, and SF volume fractions (Vf). [ABSTRACT FROM AUTHOR]

Patch repair is a method that may be applied to recover damaged concrete. Mortar can be selected as the patching material. However, certain admixtures can be added to modify this material to increase its bond strength, tensile strength, and ductility. The addition of synthetic microfibres is expected to improve the repair material's tensile performance, including its resistance to crack formation, ductility, flexural strength, and tensile strength. This research determined a direct tensile strength of repair mortars on specimens with dimensions of 10x10x25 cm with triangular cobs in the middle of the specimens. The results show that adding synthetic microfiber can increase the value of tensile strength, toughness modulus, and linear elastic energy fracture in the repair mortars. It is also found that the synthetic microfiber with a content of 0.06% gives the maximum tensile performance. [ABSTRACT FROM AUTHOR]

This study aims to determine the characteristics of the flexural strength of concrete due to the addition of Flekson additives. The approach taken is to make an experimental design with the addition of the additive Flekson. The treatment was given in the form of adding 0 %, 0.5 %, 1.0 %, and 1.5 % and age of concrete tests 1, 3, and 7 days. Flekson levels with three repetitions of each experiment. The analytical method uses a completely randomized experimental design with anova. Then proceed with regression analysis to determine the effect of the strength of the relationship between the addition of Flekson additives on the flexural strength. The results showed that the addition of Flekson additives was able to have a very significant effect on changes in the flexural strength. While the results of linear regression modeling for 7 days were obtained the power equation exponential value is 0.498 and the coefficient is 39.726 with the test results R square is 0.9669. The existence of a negative regression coefficient indicates that the addition causes a decrease in the flexural strength of concrete. However, this decrease indicates that the addition of additives provides a more flexible material condition. [ABSTRACT FROM AUTHOR]

On-site construction is being reduced these days to accomplish quick and time-saving building. In this, composite material is crucial. Performance-wise, cement-based composites outperform traditional RCC and PCC. A composite material using mortar and wire mesh for construction is Ferro cement. In this research ferrocement plates built up with Five types of meshes. The main aim of research was to inspect the effect of distinctive types of mesh as reinforcement in mortar specimen subjected to bending and select best one for future work. There are two factors of square welded mesh I.e., Diameterof wire mesh and opening of wire mesh respectively. Hence research go in two directions. In 1st case kept thickness of wire mesh constant and vary c/c opening. For this wire meshof specification 1.6mm diameter and (15 x 15) mm, (20 x 20) mm,(25x25) mm c/c opening were used respectively. In 2nd case kept opening constant and vary diameter of wire mesh. For this wire mesh of specification 15mm x 15mm opening and 1.2mm, 1.4mm,1.6mm diameter were used respectively. Total 15 numbers of specimen, 3 of each five types of size (200 x 400 x 18) mm were casted with 1:3 mix proportion mortar and 0.45 w/c ratio and tested under two-point loading systems on UTM after curing period of 28 days. The results were measured using TML strain gauge having 120-ohm resistance and 60mm gauge length. Findings demonstrate that specimens reinforced with 1.6 mm diameter and (20 x 20) mm c/c opening mesh have stronger flexural strength than the other four types of meshes. [ABSTRACT FROM AUTHOR]

This study aimed to determine the deformation pattern of compressed wood cell walls and the effect of loading directions on modulus of rupture (MOR) values of radially compressed wood in drying set condition. Hinoki (Chamaecyparis obtusa End1.) wood with a specific gravity of0.44 was used to determine the deformation pattern because it has a clear boundary between early and latewood. The deformation levels were observed at strain levels of 0.1, 0.2, and 0.3. Microscopic observations of wood cell walls were carried out using a Laser Scanning Microscope (LSM) at a scale of 200 µm. The wood samples used for bending tests were Agathis (Agathis sp.) and Rubber wood (Hevea brasiliensis) with specific gravity of 0.45 and 0.70, respectively. The wood samples were compressed in the radial direction at 0.35 strain level or 35%, after softening by using a hot press at 100°C for 4 hours until it reached drying set condition without being damaged. The results showed that the deformation of wood cell walls at a strain level of 0.1 started from the surface and the earlywood, which has thin cell walls. At strain levels of 0.2 and 0.3, the number of deformed cell walls at the surface and below the latewood increased, and only the latewood cell walls remained unchanged. MOR values of uncompressed wood in radial loading direction were almost the same as that in tangential loading direction. However, the MOR values of radially compressed wood in the tangential loading directions were higher than those in the radial loading directions. Compression in the radial direction collapsed the wood cell walls from their initial shapes to almost flats and arranged the structure tangentially. Therefore, the MOR values of radially compressed wood increased when it was loaded parallel to its tangential direction. [ABSTRACT FROM AUTHOR]

Expired glue is one of the wastes generated from the adhesive and wood processing industries. Non-optimal management of expired glue can cause financial loss and environmental danger. This research tries to utilize the expired urea-formaldehyde (UF) glue with the addition of wood vinegar for producing composite products, i.e., for plywood and recycled particleboard. The materials used in this research were urea-formaldehyde glue past ±6 months from its shelf life/expiration date, wood vinegar from mixed wood, mangium wood veneer, and rubberwood particleboard waste. The manufacture of plywood was done using a glue spread of 170 g/cm², a cold press for 10 min followed by a hot press for 3 min with specific pressure of 12 kg/cm². The particleboard was fabricated using the following conditions: 10 wt% adhesive content, press temperature of 120°C for 10 min, and specific pressure of 25 kg/cm². The addition of wood vinegar decreases solid content and adhesive acidity. Meanwhile, adding wood vinegar tends to increase both composite products' properties. The best properties of plywood and particleboard are obtained at 30% wood vinegar composition. Acacia plywood bonded with expired UF-30% wood vinegar has a dry shear strength of 16.48 kg/cm², wet shear strength of 14.89 kg/cm², and formaldehyde emission of 0.49 mg/L. Recycled rubberwood particleboard bonded with expired UF-30% wood vinegar has an internal bond strength of 3.65 kg/cm², modulus of rupture of 187.28 kg/cm², modulus of elasticity of 25149.2 kg/cm², screw-holding strength of 61.60 kg, and formaldehyde emission of 3.12 mg/L. The expired UF that has not fully hardened yet was still able to produce composite products with adequate quality, as shown by all properties of plywood and particleboard produced in this research can meet the SNI requirements. [ABSTRACT FROM AUTHOR]

Wood is the raw material that is most frequently utilized in pulp industry in Indonesia. Hardboard from the wood fiber is currently faced with limited raw materials and the issue of deforestation. The utilization of nonwood fiber materials can be used as an alternative. Several substitute nonwood fiber sources, for instance, sisal, gelagah grass, and empty palm oil fruit bunches (EPOFB), can be utilized as the primary component of hardboard. The pulping method was a semi-chemical open hot soda process using NaOH concentrations of 9.0% and 10.5%. Gelagah grass pulp, EPOFB and sisal were mixed with four composition variations and then formed into hardboard with a target density of 1.00 gram/cm3. In each formula (except for control), tannin-resorcinol-formaldehyde (TRF) was applied for adhesive (4%), wax emulsion (5%) and alum (3%) was added as an additive. The hardboard was then tested for physical and strength (mechanical) properties, including density, flexural strength (MOE), fracture modulus (MOR), moisture content, water absorption, thickness expansion, internal bond strength (IB), thermal conductivity, heat resistance as well as XRD analysis. Based on the results study, the best fiber for Hardboard was EPOFB, followed by gelagah grass and sisal. Meanwhile, in the form of mixed fiber for hardboard, the order of the most prospective proportions was EPOFB (50%) + sisal (50%), gelagah grass (50%) + sisal (50%); sisal (100%); and finally gelagah grass (33.33%) + EPOFB (33.33%) + sisal (33.33%). [ABSTRACT FROM AUTHOR]

Teak wood has always been in demand because it is famous as strong and durable timber. One of the efforts to increase the quality of the teak wood is girdling the trees before harvesting. The girdling is carried out in a circle up to the cambium part to stop the growth because new cells are not formed. This study aimed to examine the teak wood properties with different treatments before logging (ungirdled and girdled for one year). Three trees each were cut and collected at the breast-height for girdled and ungirdled treatment. The physical and mechanical properties of 80-year-old teak wood girdled for one year were identified to determine the wood characteristics using British Standards 373:1957. The results showed that the physical and mechanical properties between girdled and ungirdled treatments had no significant difference, except the green moisture content with p-values less than 0.05. In addition, the green moisture content of one-year-girdled teak wood decreased by 55% and had slightly higher physical properties (1.3%) in air-dry moisture content compared to ungirdled treatment. The mechanical properties were also slightly higher 0.2% and 2.0% at hardness and compressive strength, respectively, and modulus of rupture was higher by 5.0%. Both girdled and ungirdled teak wood are classified as strength class II. [ABSTRACT FROM AUTHOR]