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An automobile crash box is a thin walled structure made of metal or composite material which is mounted on the front region of the vehicle. Its main purpose is to absorb the energy due to collision in the event of a crash. Crash boxes made of metals like steel and aluminum are widely used whereas use of composite crash boxes is in development phase in automobile industry. In automobile industry there is always a quest to reduce the mass of the vehicle for reduction of raw material usage and also to increase fuel efficiency. Composite crash boxes provide very good weight to stiffness ratio which makes them good contenders. But the behaviour of parts made of composite material in impact or collisions has to be understood for its usage in automobile structure. Crash box plays an important role in the event of a frontal collision of the vehicle. A crash box should absorb maximum possible energy and should deform sequentially so that the deformation pattern is not random. In this paper the effect of various types of triggers is investigated for GFRP composite crash boxes. Trigger is a geometrical feature applied to the crash box with the objective of achieving the desired energy absorption, deformation pattern and peak force. A comparative study of variation of peak forces, energy absorbed, S.E.A (specific energy absorbed) was done with the variation of triggers for crash box. Force vs. displacement curves were plotted for each case providing detailed insights into the force variation during deformation. [ABSTRACT FROM AUTHOR]

The height crest profile of metal roofing sheets is the common option for Japanese factory buildings in Indonesia. The metal roofing sheets are installed on the supporting bars/ purlins with mechanical locking system without any holes. Based on this system, the paper describes how to design a similar height crest profile of roofing sheets made of a GFRP composite material that is produced in a continuous laminating machine. It was found six types of height crest profiles that are met to the profile that is installed on the purlins by mechanical locking system. The six roofing sheets structures are simulated with uniform static forces on the two local areas of valley of roofing sheets by using finite element method. Based on both stress and deflection distribution of the six finite element models of roofing sheet structure, the selected type of crest profile is the trapezoidal. The roofing sheets of GFRP material consist of three trapezoidal type crests and two valleys. It was produced in a continuous laminating machine by using seven until twenty rows of mold. A row/ set of mold consist of three parts, one bottom part and two upper parts. [ABSTRACT FROM AUTHOR]

This paper proposes a methodology that employs an experimental apparatus that reproduces, in pre-impregnated and cured out-of-autoclave Glass Fiber Reinforced Polymer (GFRP) panels, the phenomenon of slamming or impact on the bottom of a high-speed boat during planing. The pressure limits in the simulation are defined by employing a finite element model (FEM) that evaluates the forces applied by the cam that hits the panels in the apparatus via microdeformations obtained in the simulation. The methodology requires that various impact series be performed at different energies and that the evolution of the damage be followed via immersion ultrasound inspection to quantify how the material behaves, in addition to evaluating the delamination process via penetrating dyes using UV radiation. Slamming impacts were performed on the order of 10 5 , and the micromechanisms of interlaminar and intralaminar damage propagation were observed with scanning electron microscopy (SEM). The results were analyzed by correlating them with pressure, deformation, impact energy, and applied cycles, in addition to conducting compression experiments after impact to relate the material damage with the residual strength of the impacted panels. [ABSTRACT FROM AUTHOR]

Damage development due to impact needs to be understood to evaluate the consequences of impact on composite structures. This study concentrates on modelling low velocity impact and consequent compression after impact (CAI) test on thick industrial composites made from glass fiber epoxy produced by vacuum assisted resin infusion. Cross-plied laminates were tested with different impact energies and different numbers of interfaces (clustering). Results were compared to a 3D finite element analysis. Interfaces and their damage development were modelled with cohesive elements. Intraply properties were modelled by progressive failure analysis. The results show that the numerical model using only simple and independently measured material data was able to predict the impact and CAI behavior for the different energies and different stacking sequences. [ABSTRACT FROM AUTHOR]

Glass fiber composite materials in epoxy resin with different content of a nitrile rubber modified hybrid resin were manufactured by infusion with two different rubber concentrations. SX 10 epoxy resin was modified to improve the response of the laminates under impact loads. At the aim to test the improvement of the impact resistance over the conventional epoxy resin system, the rectangular specimens 100*150 mm 2 were dynamically loaded in the center by a falling weight machine, Ceast Fractovis, using a cylindrical impactor with a hemispherical nose 19,8 mm in diameter and a total mass of 3.6 kg. Impact tests were carried out at penetration to obtain the complete load-displacement curve useful to measure the penetration energy and to highlight the characteristics points for the increasing energies evaluation, 5J, 10J and 20J, to investigate the damage start and propagation. After the impact tests, the specimens were observed by visual inspection to investigate the delamination extension whereas a confocal microscope was used for the indentation measurements. The obtained results on the modified epoxy system were compared to neat GFRP laminates impact performances. No significant impact performance difference was recorded between samples with different nitrile rubber modifier content. A higher indentation was recorded on the modified samples related with a lower delamination extension. It could represent a good practical results since from a simple external damage measurement it can be possible to obtain information about a low internal delamination. [ABSTRACT FROM AUTHOR]

Structures built in the marine environment need to be carefully designed, due to the possibility of chloride ion penetration into the concrete. Among these attempts, FRP was evaluated as one of the best methods to deal with the problem because FRP does not corrode even in marine environment. This study presents the results of the application of GFRP sheet for strengthening of the concrete beams. A series of specimen of reinforced concrete beams with dimension 15×20×330 cm were cast. The samples were tested under different duration of the immersion of sea water. Beams were immersed in sea water for 1 month (BF 1 ), 3 months (BF 3 ) and 6 months (BF 6 ). Three specimens were prepared control beam without immersion to sea water (BF 0 ). The results indicated that the flexural capacity of BF 1 , BF 3 , and BF 6 when compared to that of BF 0 decreased by 2.65%, 2.73% and 3.78% respectively. The decreasing was caused by the weakening of the bonding capacity GFRP due to the influence of sea water immersion. [ABSTRACT FROM AUTHOR]

Abstract: The paper deals with realized push test of composite element (RC flanges with GFRP panel web). Connection between RC flanges and GFRP web is fixed by concrete dowels and sand-blast of GFRP surface. The results obtained from push test are compared with numerical analysis (ATENA-3D) and theoretical models which was published in technical literature. [Copyright &y& Elsevier]

Abstract: The paper informs about experimental and numerical analysis, which was aimed at monitoring the shear tension τx(i) along the anchorage zone of CFRP sheets and lamella by double tensile test and monitoring the mechanism of damage (delamination or breaking). The achieved results from the experiment are compared to numerical simulations in the FEM program (2D and 3D FEM models). The results from numerical analysis have showed the same shape of the shear tension τx(i) along the bonded effective length (Le) of CFRP sheet and shift of the peak of shear tension τmax (at higher levels of load) to reduced effective bonded length Le in comparison with the experiment. [Copyright &y& Elsevier]

Abstract: The present work is focused on the influence of cutting speed, feed rate and depth of cut on the delamination damage and surf ace roughness on Glass Fiber Reinforced Polymeric composite material (GFRP) during end milling. Taguchi design method is employed to investigate the machining characteristics of GFRP. From the results of ANOVA, it is concluded that cutting speed and depth of cut are the most significant factors affecting the responses, their contribution in an order of 26.84% and 40.44% respectively. Confirmatory experiments show that 5.052μm for surface roughness and 1.682 delamination damage to validate the used approach after conducting with optimal setting of process parameters. Finally, artificial neural network has been applied to compare the predicted values with the experimental values, the deviations are found in the range of 3.7%, it shows good agreement between the predictive model results and the experimental measurements. [Copyright &y& Elsevier]

Abstract: Shape memory alloy and piezoelectric based composites are presented for investigating the vibration characteristics. In former case, GFRP beam modeled in cantilevered configuration with externally attached SMAs. In later case, GFRP beam with surface bonded PZT patches are analysed for its vibration characteristics. The experimental work is carried out for both cases in order to evaluate the vibration control of flexible beam for first mode, also to find the effectiveness of the proposed actuators and verified numerically. As a result the vibration characteristic of GFRP beam is more effective when SMA is used as an actuator. [Copyright &y& Elsevier]

Abstract: The paper outlines results for an investigation of CO2 laser trimming of fibre reinforced plastic (FRP) composites. Process variables include cutting speed, laser beam power, gas pressure and workpiece material. These have been evaluated against key response measures involving material removal rate (MRR), surface roughness and kerf width. Higher MRRs have been obtained when trimming GFRP. Maximum MRR of 8 cm3/min was acquired when trimming GFRP at 1750mm/min, 5bar and 2500 watt respectively. Scanning electron microscope (SEM) analysis revealed that matrix constituent in both composites incurred to elevated cutting temperature which most likely resulted in a charring/melting and adhered to the cut surface which adversely affected its quality (Ra of up to ∼ 6μm). Maximum entry kerf width of 0.5mm and 0.28mm was measured for GFRP and CFRP samples respectively. [Copyright &y& Elsevier]

Abstract: Glass Fiber-Reinforced Polymer (GFRP) composites are more and more used in the building trade for the set up of reinforcing and strengthening applications devices. As known, GFRP composites offer higher strength and Young modulus than traditional steel devices. The majority of these buildings were built before any provisions for earthquake loadings were established. The failures and damages reported in recent earthquakes attest to the need for efficient strengthening procedures. The effectiveness of increasing the shear strength of brick masonry coating with epoxy-bonding by Glass Fiber-Reinforced Polymer (GFRP) overlays to the exterior surfaces was evaluated. Out-of-plane failures are common in unreinforced masonry wall (UMW) constructed in seismic regions. This paper deals with the experimental characterization of the mechanical tensile and shear bond behavior of Glass Fiber-Reinforced Polymer (GFRP) sheets externally glued on masonry wall, in terms of load capacity and stress distribution along the bonded length. A combined experimental program was conducted to study the out-of-plane shear behavior of (i) Burned Clay Brick Masonry Walls and (ii) Strengthened with Glass Fiber Reinforced Polymer (GFRP) over the Burned Clay Brick Masonry Walls surface. [Copyright &y& Elsevier]

Abstract: In recent years, the use of externally bonded fiber-reinforced polymers (FRP) has become increasingly popular for civil infrastructure applications. The Glass fiber reinforced polymer has significantly enhanced the strength and ductility of concrete by forming perfect adhesive bond between concrete and the wrapping material. Present experimental investigation mainly emphasises on effectiveness of external GFRP strengthening for RC Columns of circular, square and rectangular shapes having same cross sectional area. Total 15 RC columns of 1 meter in height were cast. 9 columns were control and the rest 6 columns were strengthened with one layer of GFRP wrap having 20mm of corner radius. Columns were designed using IS: 456:2000 provisions. Design of GFRP wrapping was done using ACI 440.2R.08 provisions. All the test specimens were loaded to fail in axial compression and strain of the columns in the axial direction was investigated. The test results clearly demonstrated that the axial load carrying capacity increases from rectangular to square to circular shape of confined RC columns. No major impact on axial compressive strength is observed due to variation in shape for control columns, on the other hand, quite opposite behaviour was observed in case of RC columns confined by GFRP. GFRP wrapped circular column undergone more axial deformation as compared to that of square and rectangular columns. Stress-strain behaviour revealed that the strength gained from FRP confinement was prominent for circular columns. Square and rectangular-section columns are found to experience lesser increment in strength as compared to that of circular columns. This behaviour may be attributed to variation in lateral confining pressure distribution for rectangular columns from a maximum at the corners to a minimum in between, which is in contrast to even confining pressure observed for circular columns in order to achieve the full confinement effect. [Copyright &y& Elsevier]

Abstract: Existing reinforced concrete (RC) columns may be structurally deficient due to variety of reasons such as improper transverse reinforcement, flaws in structural design, insufficient load carrying capacity, etc. Carbon/Glass fibre reinforced polymer (FRP) confinement can be effectively used for strengthening the deficient RC columns. The effectiveness of FRP wrapping for RC columns mainly depend upon corner radius of the specimens as well as number of FRP layers used for the confinement. An attempt has been made hereby to investigate the experimental behaviour of GFRP wrapped small scale square RC columns with varying corner radii. Experimentally evaluated behaviour of GFRP wrapped RC columns is compared with the performance observed for non-wrapped RC columns. 15 RC columns having cross-sectional dimensions 125mm × 125mm and length of 1200mm have been tested under axial compression. Three columns are unwrapped and have been designated as control specimens. Three columns each with corner radius equivalent to cover of 25mm are wrapped with one and two layers of GFRP, respectively. To avoid a premature rupture of the GFRP composite, remaining six columns with corner radius of 5mm have been wrapped with one and two layers of GFRP, respectively. GFRP wrapped columns go under higher axial displacement in order to gain higher compressive strength over the control column. The results showed that smoothening of the edges of square cross-section of RC columns play a significant role in delaying the rupture of the FRP composite at the edges. Corner radius equal to concrete cover gives better results in terms of ultimate load carrying capacity than the corner radius less than cover for confined RC columns. [Copyright &y& Elsevier]

Abstract: The aim of the research is design and analysis of new bridge deck panel made of glass fiber reinforced polymer (GFRP). Use of GFRP in construction is rapidly growing in last few years. The reason for use GFRP is its low self weight in compare of strength and high resistance against weather influenced degradation resulting in long life. Using GFRP for the construction of the bridge deck leads to lightweight construction that can pass the required wheel load. Lightweight design is appreciated for temporary bridge which is expected to be transported and assembled often on places of current need. Long durability and resistance against weather degradation also reduces maintenance costs of bridge deck. Design of deck panel will be done on the base of loading experiments and FEM analysis. The main use of GFRP bridge deck panel is for temporary bridge but it is possible to extend its use on permanent or movable bridges. [Copyright &y& Elsevier]

Abstract: Analyses of cutting tools (solid carbide end mill) behavior on advanced materials like Glass Fiber Reinforced Plastic (GFRP) are very important in manufacturing industries. In this paper Grey Relational Analysis (GRA) approach was used for study and optimization of the machining parameters(Tool condition (TC), number of flutes (z), cutting speed (V) and feed rate (f)) on milling of GFRP in order to minimize surface delamination, machining forces, cutting torque and surface roughness. For this study; GFRP was fabricated by hand layup with 33% fiber and 66% general purpose resin. Experiments were designed & carried out as per orthogonal array and parameters were optimized using Grey Relational Grade (GRG). [Copyright &y& Elsevier]

Abstract: In order to replace a conventional steel bogie to a composite one, in this study, a GFRP composite bogie frame has been designed and manufactured to be applied to the bogie of urban subway trains. To evaluate the structural behavior, the compositebogie frame was manufactured using the autoclave curing method and tested under the critical load conditions; vertical loads andtwisting load. Through the test, the stresses at the connection region between a cross beam and a side beam and deflection weremeasured and used to assess the structural safety. Moreover, the stress and strain distribution for the whole bogie frame was evaluated through finite element analysis and compared with the experimental results. [Copyright &y& Elsevier]