Investigation on failure modes for pin joints made from unidirectional glass–epoxy nanoclay laminates

Abstract

A B S T R A C T In the present work the effect of the nanoclay on the bearing strength and failure mode of the pin joints was investigated both experimentally and numerically. Geometric parameters, i.e. the distance from the free edge of specimen to the diameter of the first hole (E/D) ratio and width of the specimen to the diameter of the holes (W/D) ratio were investigated. The E/D and W/D ratios were varied from 1 to 5. Tsai-Wu failure criterion with characteristic curve method and progressive damage analysis was used for the prediction of failure modes. Results showed that bearing strength and failure mode were considerable affected by the wt% of nanoclay and the geometric parameters. A good agreement was obtained between experimental and numerical predictions.Keywords characteristic curve; failure analysis; glass reinforced; nanoclay; pin joint; progressive damage failure. N O M E N C L A T U R Es = shear failure strength t = thickness of the specimen B = bearing failure mode D = diameter of the hole E = distance from the free edge of specimen E F = flexural modulus E 1 = longitudinal tensile modulus E 2 = transverse tensile modulus G 12 = shear modulus N = net-tension failure mode R c , R ot , R oc = characteristic curve parameters S = shearing failure mode v 12 = Poisson ratio W = width of the specimen X c = longitudinal compressive strength X t = longitudinal tensile strength Y c = transverse compressive strength Y t = transverse tensile strength ε F = strain to failure θ = failure angle σ b = bearing stress σ F = flexural strength I N T R O D U C T I O NIn the last decade, composite materials are being commonly used in structures that demand a high level of mechanical performance. Their high strength to weight and stiffness to weight ratios has facilitated the development of lighter structures, which often replace conventional metal structures. Fibre-reinforced composites offer the most reliable engineering materials in automotive, marine and aircraft industrial engineering applications because of their outstanding mechanical properties like impact resistance, high durability, low coefficient of friction and thermal expansion, ability to provide higher

To study the contribution of different geometric parameters on the failure load for multi holes pin joints prepared from glass/epoxy nanoclay laminates

“…Multiple pins are important to increase the loading capacity of the joints. The authors are extending their previous work 11,15,24 for multi-pin joints. The present work studies the contribution of each geometric parameter on the strength of the three and four holes pin joints.…”

“…The above procedure was also discussed by Singh et al. 11,15,24 for the preparation of the laminates. It was investigated by Singh et al.…”

“…Tsai–Wu failure theory 30 was used to predict the value of FI on the characteristic curve as was discussed by Singh et al. 11,15,24 FI is a dimensional-less numerical constant whose value is calculated using equation (3). All the relevant equations are also discussed in the author’s previous work.…”

“…Singh et al. 15 investigated the failure modes of pin joint prepared from unidirectional nanoclay glass-epoxy laminates. Single-hole pin-loaded specimens were tested for their tensile strength and failure modes both experimentally and numerically.…”

The effect of radiation curing on mechanical joints prepared from carbon nanotubes added carbon/epoxy laminates

“…Bearing strength enhanced with increased filler content in the composite pin joint. Singh et al [ 22 ] incorporated nanoclay into the glass/epoxy composites to study the load‐bearing capacity and failure loads and modes of pin joints. For prediction of failure modes, Tsai‐Wu failure criteria along with progressive damage analysis (PDA) and characteristic curve method was used.…”