Flexural rigidity

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

Effects of carbon nanotube inclusion into the carbon fiber reinforced laminated composites on flexural stiffness: A numerical and theoretical study

Abstract: Because of increased usage areas, and advances in characterization of the nanostructured materials, determination of the engineering properties of composites that includes carbon nanotubes has gained importance. It is possible to designate material properties of carbon nanotube based composites theoretically and experimentally. In this study, engineering constants of carbon nanotube based unidirectional carbon fiber reinforced composite lamina determined theoretically with two different approaches. Then, a composite plate whose laminas were stacked up as a [0°/+45°/-45°/90°]s layup was built up in ANSYS, ACP Module. Finally, three point bending analyzes were performed separately under concentrated and distributed load. The results showed that there were negligible differences between the engineering constants obtained from two different theoretical approaches. Engineering constants, E1, E2, G12 and G23, increased as the added carbon nanotube fraction is increased. Besides that, flexural rigidity of composite plate also showed ever-decreasingly increase, as carbon nanotube content is increased. The results of theoretical and numerical bending analyzes exhibited a good agreement with the maximum percentage relative error of 9.1.

Tire Stress and Deformation from Composite Theory

Abstract: The pneumatic tire is treated as a laminated, anisotropic, toroidal shell of revolution possessing bending rigidity. The plies, which are constructed of elastic textile cords embedded in an elastic rubber matrix, are considered homogeneous and orthotropic on a macroscopic scale. The tire shell is considered to deform according to the classical Love hypothesis. The equilibrium, strain‐displacement, and laminate constitutive equations governing the tire shell are reduced to a system of six first order, nonlinear, ordinary differential equations with variable coefficients which are solved numerically by a multi‐segment forward integration technique. The geometrical nonlinearities due to finite displacements are accounted for by an incrementing process using transient coordinates. The theory is illustrated by a numerical calculation which shows good agreement with actual measurements.

The Relationship between Fabrics Bending Rigidity Parameters Defined by KES-F and FAST Equipment

Abstract: having comparatively high area density which varied in the range of 211 g/m 2 – 398 g/m 2 . In parallel comparative analysis of BKESF and BFAST bending rigidity parameters provided in literature references was performed. Data of 80 different fabrics was analysed. The results of the investigation present the dependencies which allow to convert BFAST bending rigidity values into BKESF values. The differences between light-weight and heavy-weight fabrics are analyzed from the standpoint of KES-F and FAST testing results.

Mechanical performance of concrete-filled square steel tube stiffened with PBL subjected to eccentric compressive loads: Experimental study and numerical simulation

Abstract: This paper describes an experimental study on the flexural and eccentric compressive behavior of concrete-filled square steel tube (CFSST) beam-columns stiffened with PBL stiffeners. Three types of CFSST beam-columns were fabricated and tested under the flexural moment and eccentric compressive load. Among the three types of columns, the two types of columns were strengthened with the PBL and steel plate stiffeners; the other type of columns was not strengthened. In addition, extensive finite element analyses (FEA) were carried out to evaluate the stress distribution. Flexural test results show that failure modes of specimens without stiffeners were different from specimens with the PBL or steel plate stiffeners. The results also demonstrate the distribution of cracks in the concrete was affected by stiffeners and the columns with the PBL stiffeners have the most uniformed crack distributions. The capacity improved by the PBL stiffeners was insignificant. However, the flexural stiffness of the specimen stiffened with the PBL stiffeners was about 20% larger than the unstiffened specimen. Eccentric compressive load test results show the capacity of specimen with the PBL stiffeners was 6.95% larger than the unstiffened specimen. The eccentric compressive capacity decreased with the increase of the eccentricity ratio or slenderness ratio. FEA results show that stiffeners can effectively improve the mechanical behavior of CFSST specimens under bending and eccentric compressive loads.