Title: Nonlinear Angle-ply Model for Stay in Place Tubes by Inverse Mechanics Approach

Author(s): Hayder A. Rasheed

Publication: Symposium Paper

Volume: 327

Issue:

Appears on pages(s): 11.1-11.16

Keywords: Nonlinear Angle-Ply Model, Stay in Place Form Tubes, Constitutive Behavior, Inverse Problem, Symmetric Laminates

DOI: 10.14359/51713331

Date: 11/1/2018

Abstract:
Standard constitutive modeling of fiber-reinforced polymer composite laminates is typically based on uniaxial properties. The nonlinear in-plane shear behavior, of angle-ply laminates, is recognized long ago. This paper presents a model using test data generated from (±55o)ns symmetric angle-ply coupons to determine material response using an inverse mechanics approach. Nonlinear classical lamination theory is used to assemble the ply constitutive properties for global axial tensile response in terms of the secant shear modulus G12s values. The main objective of this study is to obtain the nonlinear in-plane shear stress-strain curves along the principal fiber-matrix direction. The resulting full-range material model is used to predict the response of (±55o)4s angle-ply FRP tubes used for stay in place form members manufactured by the filament winding process. The resulting analysis procedure accurately predicts the ultimate moment of the concrete filled tube and traces the deformation response reasonably well. In addition, the load-deflection analysis of the entire tube is performed and found to match well the experimental curve up to the limits of nonlinear material analysis when the large deformation of the tube is ignored.