This paper discusses the effect of misalignments in ply orientation, uniform variations in ply thickness, and through-thickness thermal gradients on the post-cure shape errors for symmetric cross-ply laminates constructed from ultra-thin composite materials. Photogrammetry-based surface measurements are performed for laminates cured at elevated temperatures. Significant out-of-plane shape error...

Many opportunities are becoming available for using composite materials to strengthen/upgrade existing reinforced concrete (RC) structures. This paper focuses on a new technique for the seismic upgrade of RC beam-column connections in gravity load-designed (GLD) frames by the application (combined or not) of FRP rods and laminates. The FRP rods provide flexural strengthening, whereas the lay-up...

On the basis of the theory of three-dimensional elasticity, this paper presents a state space finite element solution for the stresses in cross-ply laminates subjected to combined transverse and in-plane loads. The state space formulation is introduced to solve for through-thickness stress distributions, while the traditional finite elements are used to approximate in-plane variations of the st...

Abstract. Generally one encounters a substantial variation in the mechanical properties of composite laminates. This is due to the fact that a large number of parameters have to be controlled during the manufacturing process. The dispersion in the material properties can best be accounted for by modelling these as random. In this paper, FEM in conjunction with Monte Carlo Simulation is employed...

Delaminations in composite laminates resulting from impact events may be accompanied by minimal indication of damage at the surface. As such, inspection techniques are required to ensure defects are within allowable limits. Conventional ultrasonic scanning techniques have been shown to effectively characterize the size and depth of delaminations but require physical contact with the structure. ...

The incorporation of a model protein, bovine serum albumin (BSA), into poly(vinyl alcohol) (PVA) hydrogel films during the freezing and thawing process and its subsequent release behavior were investigated. The effect of the number of freezing and thawing cycles as well as the stability of BSA were examined. BSA release profiles were not significantly different from gels prepared after 3 or 5 c...

Flexible barrier films preventing permeation of gases and moistures are important for many industries ranging from food to medical and from chemical to electronic. From this perspective, graphene has recently attracted particular interest because its defect-free monolayers are impermeable to all atoms and molecules. However, it has been proved to be challenging to develop large-area defectless ...

Problem statement: This study showed the results of an experimental investigation on the strengthening of corrosion damaged reinforced concrete beams with unidirectional cloth glass fiber reinforced polymer (UDCGFRP) laminates. Approach: All the beam specimens 150×250×3000 mm were cast and tested for the present investigation. One beam specimen was neither corroded nor strengthened to serve as ...

T he use of fiber reinforced polymers (FRP) for reinforcement of aging and deteriorating concrete members has emerged as a viable and costeffective alternative to traditional repair and strengthening techniques. Their use enables upgrading of deficient structures to meet today’s design standards (Crasto et al., 1996; Myers et al., 2000). The loadcarrying ability of structures such as beams and ...

Considerable efforts have been made in recent years to develop quantitative nondestructive evaluation (NDE) techniques for composite materials, which are being used increasingly in primary structures. The leaky Lamb wave phenomenon has shown considerable potential as an NDE method [1]. Most results reported in this area to date have been concerned with unidirectional laminates [2-4]. This is at...