A NURBS-based isogeometric finite element formulation is developed and adopted to the free vibration analysis of finite square and skew laminated plates. Variable stiffness plies are assumed due to implementation of curvilinear fiberreinforcements. It is assumed due to employment of tow placement technology, in each ply of variable stiffness composite laminated plate the fiber reinforceme...

Fiber Bragg grating(FBG) sensors, one of the fiber optic sensors(FOS), based on the wavelength division multiplexing(WDM) technology are ideally suitable for structural health monitoring of composite materials and structures. Proper monitoring of measurands in FBG sensor systems requires accurate measurement of the Bragg center wavelength, and the ability to track rapid shifts of the wavelength...

This paper presents a Bayesian approach for optimizing the position of sensors aimed at impact identification in composite structures under operational conditions. The uncertainty in the sensor data has been represented by statistical distributions of the recorded signals. An optimisation strategy based on the genetic algorithm is proposed to find the best sensor combination aimed at locating i...

One method of constructing lightweight concrete floors in residential dwellings is to use a trapezoidal profile steel pan as a permanent form for a relatively thin pour of concrete. The resulting structure has enhanced stiffness to weight ratio due to the composite action between the steel and concrete, and the inherent improved stiffness of the profiled cross section. However the floor is stro...

the impact resistance of new lightweight panel is studied. this panel consists of two thin metal layers bonded together by intermediate fiber/epoxy layers (mcm-sheets). to simulate a behavior of this kind of impact problem, explicit and implicit finite element software abaqus is used. in order to validate the finite element modeling, these results have been compared with experimental test resul...

The cohesive element approach is proposed as a tool for simulating delamination propagation between a facesheet and a core in a honeycomb core composite panel. To determine the critical energy release rate (Gc) of the cohesive model, Double Cantilever Beam (DCB) fracture tests were performed. The peak strength (σc) of the cohesive model was determined from Flatwise Tension (FWT) tests. The DCB ...

This study presents results from an effort to fabricate a shape memory alloy hybrid composite (SMAHC) panel specimen and test the structure for dynamic response and noise transmission characteristics under the action of thermal and random acoustic loads. A method for fabricating a SMAHC laminate with bi-directional SMA reinforcement is described. Glass-epoxy unidirectional prepreg tape and Niti...

In this paper an experimental-numerical approach is presented to tackle the vibro-acoustic characterization of composite sandwich structures. A novel experimental setup allows for fast and comprehensive understanding of the NVH behaviour of composite sandwich panels. This information can then be further exploited in numerical model updating and design tools for optimized solutions. Experimental...

The effects of adding an extra layer within a sandwich panel and two different core types in top and bottom cores on low velocity impact loadings are studied experimentally in this paper. The panel includes polymer composite laminated sheets for faces and the internal laminated sheet called extra layer sheet, and two types of crushable foams are selected as the core material. Low velocity impac...