Flexural rigidity

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

Relation between Drape Coefficients and Mechanical Properties of Fabrics

Abstract: In this paper, drape coefficients and mechanical properties of 138 samples of woven fabrics are measured, and the relation between them is analyzed by means of residual-regression method. A linear equation by which the drape coefficient can be calculated from the mechanical properties is presented.As a result, it is shown that the value given by 3√ is most related with the drape coefficient, where B is bending rigidity (g•cm2/cm), W weight per unit area of fabric (mg/cm2).Next, the anisotropy in the bending property of fabric is examined, and we get an equation for the drape coefficient, by means of multiple regression method; Dn; =5.1+115.03√ +131.13√ +1.23√ where B90; is bending rigidity (g•cm2/cm) along warps, B0; along wefts, and B45; in bias directions.Finally, the stability of the drape shape is examined. It is found that as the hysteresis in fabric shearing and bending is large, the instability in the drape coefficient increases. From this fact, the experimental technique of drape testing is also discussed.

Seismic behavior and modeling of steel reinforced concrete (SRC) walls

Abstract: Summary The steel reinforced concrete (SRC) wall consists of structural steel embedded at the boundary elements of a reinforced concrete (RC) wall. The use of SRC walls has gained popularity in the construction of high-rise buildings because of their superior performance over conventional RC walls. This paper presents a series of quasi-static tests used to examine the behavior of SRC walls subjected to high axial force and lateral cyclic loading. The SRC wall specimens showed increased flexural strength and deformation capacity relative to their RC wall counterpart. The flexural strength of SRC walls was found to increase with increasing area ratio of embedded structural steel, while the section type of embedded steel did not affect the wall's strength. The SRC walls under high axial force ratio had an ultimate lateral drift ratio of approximately 1.4%. In addition, a multi-layer shell element model was developed for the SRC walls and was implemented in the OpenSees program. The numerical model was validated through comparison with the test data. The model was able to predict the lateral stiffness, strength and deformation capacities of SRC walls with a reasonable level of accuracy. Finally, a number of issues for the design of SRC walls are discussed, along with a collection and analysis of the test data, including (1) evaluation of flexural strength, (2) calculation of effective flexural stiffness, and (3) inelastic deformation capacity of SRC walls. Copyright © 2014 John Wiley & Sons, Ltd.

An experimental study on mechanical properties of GFRP braid-pultruded composite rods

Abstract: In this work, a conventional textile braiding machine was modified and added to a pultrusion line in order to pro- duce glass fiber reinforced composite rods by braiding-pultrusion technique. Braid-pultruded (BP) rods were produced with three braid roving linear densities and also with three different braid angles. To study the influence of overbraiding on mechanical properties of pultruded rods, unidirectional (UD) rods, without braided fabric, were produced, as well. All rod types were subjected to tensile, bending and torsion tests. The experimental results showed that BP rods have considerably higher shear modulus, but lower tensile modulus and flexural rigidity than those of UD pultruded rods, when fiber volume fraction is kept constant. Moreover, rods produced with higher braid roving linear densities had better torsional, but lower tensile and flexural properties. The highest shear modulus was observed in BP rods with braid angle of 45°.

Stability Functions for Three‐Dimensional Beam‐Columns

Abstract: Members carrying both axial force and bending moment are subjected to an interaction between these effects. The analysis of a beam-column using stability functions as an alternative to the stress stiffness matrix is discussed. Explicit expressions for stability functions for three-dimensional beam-columns, in terms of member length, cross-sectional properties, axial force, and the end moments, are derived. The effect of flexure on axial stiffness and the effect of axial force on flexural stiffness and stiffness against translation are considered in the derivation of stability functions. The effect of axial force on torsional stiffness and the effect of torsional moment on axial stiffness are neglected. The nonlinear stiffness matrix of a three-dimensional beam-column using the stability functions is presented by modifying the linear elastic stiffness matrix for a beam-column (which includes the effect of shear deformations) available in the literature. A numerical example showing the calculation of stability functions for a given beam-column is also presented.