Flexural rigidity

About: Flexural rigidity is a research topic. Over the lifetime, 3829 publications have been published within this topic receiving 56780 citations.

Characterization of Statical Properties of Rat's Whisker System

Abstract: This contribution describes mechanical properties of the whisker system of rats. The motivation for the work was to achieve a better understanding of the functionality of this remarkable sense organ by defining structure-function-correlations. Special features of the different types of whisker are interpreted in terms of their morphological background, e.g., object recognition and texture discrimination. The whiskers are found to be conical in shape. Theoretical considerations of rod types reveal certain advantages of conically shaped rods over cylindrical rods. There is a difference in deformation, with the higher values applying to conical rods. Whiskers have a very flexible tip which is sensitive to very small forces. Uniaxial bending tests using actual whiskers were performed to characterize the static parameters. From experimental data obtained, the spring constant, the Young's modulus and the flexural stiffness are calculated. Young's modulus is one standard parameter for the characterization of materials. It was found that this can be regarded as constant along the whiskers with an average value of 7.36 GPa. Flexural stiffness was found to depend on the hair diameter and decrease from base to tip. The short vibrissae exhibit the lowest flexural stiffness, which means they are sensitive to very small forces. The experimental results obtained might well be used as a basis for the optimization or the construction of bioinspired technical sensor systems.

Effect of Strain-Rate on Flexural Behavior of Composite Sandwich Panel

Abstract: In the past few decades, Composite Sandwich Panel (CSP) technology significantly influenced the design and manufacturing of high performance structures. Although using CSP increases the reliability of structure, the important concern is to understand the complex deformation and damage evolution process. This study is focused on the mechanical behaviour of CSP under flexural loading condition. A setup of three-point bending test is prepared using three support span of 40, 60 and 80 mm. The loading was controlled by three different displacement rates of 1, 10 and 100 mm per minute to examine the effects of strain-rate on bending behaviour of CSP material. The beam span significantly affects the flexural stiffness of CSP panel. The load-deflection response of the panel shows two different portions, that representing equivalent elastic and plastic regions in both the core and facesheets components of CSP. The non-combustible mineral-filled core appears to be nonlinear in the elastic region, at high loading rate. Consequently the failure occurs as the core/facesheets interface suffers debonding.

Measurements of sea-ice flexural stiffness by pressure characteristics of flexural-gravity waves

Abstract: A method to estimate the flexural stiffness and effective elastic modulus of floating ice is described and analysed. The method is based on the analysis of water pressure records at two or three locations below the bottom of floating ice when flexural-gravity waves propagate through the ice. The relative errors in the calculations of the ice flexural stiffness and the water depth are analysed. The method is tested using data from field measurements in Tempelfjorden, Svalbard, where flexural-gravity waves were excited by an icefall at the front of the outflow glacier Tunabreen in February 2011.

Finite element modelling of the flexural performance of resorbable phosphate glass fibre reinforced PLA composite bone plates.

Abstract: A finite element method is presented to predict the flexural properties of resorbable phosphate glass fibre reinforced PLA composite bone plates. A novel method for meshing discontinuous fibre architectures is presented, which removes many of the limitations imposed by conventional finite element approaches. The model is used to understand the effects of increasing the span-to-thickness ratio for different fibre architectures used for PBG/PLA composites. A span-to-thickness ratio of 16:1 is found to be appropriate for materials with randomly orientated fibres, which agrees well with the test standard. However, for highly aligned materials the model indicates that a span-to-thickness ratio of 80:1 is required, in order to minimise the effects of shear deflection. The model is validated against flexural stiffness data from the literature for a range of polymers, fibres and fibre volume fractions. Generally there is less than 10% error between the FE predictions and experimental values. The model is subsequently used to perform a parametric study to understand what material developments are required to match the properties of PGF/PLA composites to cortical bone. It is concluded that alignment of the fibre is necessary to exceed the 20 GPa target, since the current manufacturing methods limit the fibre length to ∼10 mm, which consequently restricts the flexural modulus to ∼19 GPa (at 50% volume fraction).