Papers by Keyword: Glass Fiber Reinforced Polymer (GFRP)

Abstract: This study explained the potential use of glass fiber-reinforced polymer (GFRP) composite materials as an alternative lined material for irrigation channels in Indonesia. Currently, only four recommended materials are used as lining in irrigation channels in Indonesia, i.e., stone masonry, concrete, soil-cement, and ferrocement. Almost all lined material's main constituents are sourced from nature/environment. The exploitation of these mined materials will impact environmental destruction. This study focused on the manufacturing process of GFRP material, GFRP surface roughness testing, and the water flow characteristics in the hydraulic model experimental testing. The manufacturing process of GFRP material used polyester resin as the polymer matrix, E-glass type with a combination of woven roving mat covered by non-woven standard mat as the glass fiber reinforcement, and manufacturing process with a combination of hand lay-up and spray-up techniques. The GFRP material product has an average surface roughness coefficient value of R_a around 5.19 to 5.97 μm. The GFRP manufacturing has a good uniform product, as the average surface roughness coefficients of GFRP material have relatively the same values. It is shown that a factory in Indonesia has sufficient capacity to manufacture GFRP material for lining in open channels. The water flow characteristics in the flume were turbulent during testing in the hydraulic laboratory. The experimental study concluded that the GFRP composite materials could be implemented as preliminary references for alternative lined material in irrigation channels in Indonesia.

Abstract: Fiber reinforced polymeric (FRP) composite materials are currently used in numerous structural and materials related applications. But, during their in-service period these composites were exposed to different changing environmental conditions. Present investigation is planned to explore the effect of thermal shock exposure on the mechanical properties of nanoTiO₂ enhanced glass fiber reinforced polymeric (GFRP) composites. The samples were conditioned at +70°C temperature for 36 h followed by further conditioning at – 60°C temperature for the similar interval of time. In order to estimate the thermal shock influence on the mechanical properties, tensile tests of the conditioned samples were carried out at 1 mm/min loading rate. The polymer phase i.e. epoxy was modified with different nanoTiO₂ content (i.e. 0.1, 0.3 and 0.5 wt. %). The tensile strength of 0.1 wt.% nanoTiO₂ GFRP filled composites exhibited higher ultimate tensile strength (UTS) among all other composites. The possible reason may be attributed to the good dispersion of nanoparticles in polymer matrix corresponds to proper stress transfer during thermal shock conditioning. In order to access the variations in the viscoelastic behavior and glass transition temperature due to the addition of nanoTiO₂ in GFRP composite and also due to the thermal shock conditioning, dynamic mechanical thermal analysis (DMTA) measurements were carried out. Different modes of failures and strengthening morphology in the composites were analyzed under scanning electron microscope (SEM).

Abstract: In oil distribution process, especially in archipelago countries like Indonesia, jetty is anessential tool in loading and unloading oil from and to tanker. The main problem in jetty structurewith steel piling is its corrosion resistance. The deterioration of the jetty structure strength was causedby the piling depletion caused by corrosion. In this study, calculation and mechanical strength testingfor Glass Fiber Reinforced Polymer (GFRP) were conducted. The study was then applied toPertamina Tanjung Uban jetty to strengthen the piling, and increase in compression strength of up to63.38% was observed. The increase of compression strength from the application of GFRP however,doesn’t have a linear strengthening effect when applied for other applications.

Abstract: Many areas of Europe, especially Italy, Greece, Slovenia and other Balkan States, are generally associated with earthquakes. In the last two decades Fiber Reinforced Polymers (FRP) have gained an increasing interest, mostly for upgrading, retrofitting and repair of masonry and timber structures belonging to the architectural heritage. Recent researches demonstrated that masonry constructions or single structural elements are likely to be effectively repaired or enhanced in their mechanical properties using FRPs. The objective of the research presented in this paper is to study the long-term behavior of composite grids, made of E-CR glass fibers and epoxy-vinylester resin, subjected to harsh environmental factors including fatigue loading and ageing in aqueous solution. The paper presents new original test results on the relationship between the durability and the governing material properties of GFRP (Glass Fiber Reinforced Polymers) grids in terms of tensile strength and axial strains, using specimens cut off from GFRP grids before and after ageing in aqueous solution. The tensile strength of a GFRP grid was measured after conditioning in alkaline bath made by deionized water and Ca(OH)₂, 0.16% in weight, solution. The reduction in terms of tensile strength and Young’s modulus of elasticity compared to unconditioned specimens is illustrated and discussed. This degradation indicated that extended service in alkaline environment under fatigue loads may produce reductions in the GFRP mechanical properties which should be considered in design, where cyclic loads and aggressive conditions are prevented in service life.

Abstract: External bonded reinforcements (EBR), made by fibrous meshes embedded in a cementitious/hydraulic lime mortar, are getting a great deal of attention, mostly for strengthening, retrofitting and repair existing structures. In this context, the interest versus the FRCM (Fiber Reinforced Cementitious Matrix) is growing. The mechanical performance of these mortar-based reinforcements is not well known at the date and it needs to be investigated in terms of bond and tensile strength, strain and stiffness, in relation to the type of both substrate and fibers. The present work reports the results of an experimental study, still in progress, on different pre-cured GFRP grids embedded in inorganic matrices and applied on clay brick masonry. First, the mechanical properties of both pre-cured GFRP grid and GFRCM reinforcements were obtained through tensile tests. Then, the experimental investigation on bond behavior was carried out by direct shear bond test. The test results were collected and processed to evaluate bond strength, failure mode, load-slip relationship.

Abstract: This paper presents the results of an experimental campaign aimed to evaluate the performance of timber beams strengthened in bending using GFRP (Glass Fiber Reinforced Polymer) plates mechanically attached with high-strength metal screws. Modest ratios of GFRP composite reinforcement can increase beam load-carrying capacity and manipulate failure mode from the brittle tensile in the unreinforced beams to a more extensible failure in the strengthened timber beams. Application of mechanical reinforcement presents a solution of reversibility, compatibility and durability for reinforced timber. The experimental campaign focused on load-deflection relationship and failure modes in order to increase the bending capacity and stiffness of the timber beam. Oak beams with dimensions 145 x 145 x 2450 mm were reinforced with un-bonded pultruded GFRP plates. Hexagon head coach screws 16 mm diameter, 130 mm length, grade 8.8, were used to mechanically attach the reinforcement along with 34 mm outer diameter fender washers, distributing the fastening load away from the screw’s position. All beams were tested until failure under the four-point bending configuration. Experimental results demonstrate the effectiveness of the reinforcement method and ability to reversibly repair the timber, representing a capability to be utilised in the new constructions or restoration of timber structures.

Abstract: The application of structural insulated panels (SIP) was mainly limited to wall panels in the past. In order to evaluate the flexural performance of SIP two-way slabs, an experimental research on the flexural behavior of four full-size two-way slabs, made of SIP panels or fiber reinforced structural insulated panels, was presented in this paper. The bending capacities and the strains in the face layers were studied and compared with those of ordinary reinforced concrete two-way slabs. Testing results verified that, strengthening of glass fiber reinforced polymer sheets could obviously improve the flexural capacity of SIP slab. Fiber reinforced structural insulated panels could substitute ordinary reinforced concrete slabs in residential or light commercial buildings.

Abstract: This research determined the seismic behavior of historic masonry walls retrofitted by Glass Fiber Reinforced Polymer (GFRP) sheets through laboratory testing. Brick and mortar were special prepared to get the same properties as that of historic walls. Five full scale wall specimens were constructed according to the dimension of historic walls in Thailand and tested to failure under horizontal cyclic loading. One wall served as reference specimen without retrofitting. Three walls were retrofitted with GFRP in different patterns before subjected to lateral loading. One wall was repaired after predefined shear damage and retrofitted with GFRP before taken the new loading test. Failure mechanism, shear strength, ductility and energy dissipation of walls were studied in detail. The results showed that the walls retrofitted with GFRP sheets in the same strengthening ratio on one side or two sides exhibited the similar improvement on deformation and shear capacity. The wall retrofitted with diagonal GFRP strips behaved the better energy dissipation capacity and more dense and adequate cracking development.

Abstract: In this study, the impact responses for GFRP type C-600 and GFRP type E-800 have been investigated. Impact tests were performed using a drop weight tester, IMATEK IM10T with eight different levels of energy ranging from 6 J to 48 J. The variation of impact characteristics such as peak displacement, peak force and energy absorbed versus impact energy and damaged area were investigated. From the experimental studies, it can be concluded that for each type of GFRP, the impact energy showed excellent correlation with the impact characterization and the damaged area. The difference in the thickness and mechanical properties for both types of GFRP do affect the impact characterization and the damaged area of the specimens tested. It can be concluded that GFRP type E-800 is higher in strength compared to GFRP type C-600.

Abstract: The experimental studies of flat and relief glass-plastic reinforcement bond with concrete were conducted. The comparative analysis of obtained experimental data with results of other researchers in field of reinforcement and concrete bond was made. It was identified that composite reinforcement with flat winding has better bond characteristics in comparison with steel reinforcement and other winding types composite reinforcement. The analytical dependencies, allowing to simulate the process of fiber-plastic reinforcement bond with concrete, were obtained. The finite element modeling of deformation process of concrete foundation of transport constructions with fiber-plastic reinforcement were made.