REPUBLIC OF SERBIA

MINISTRY OF DEFENCE

www.mod.gov.rs

MINISTRY OF DEFENCE

Material Resources Sector

Defensive Technologies Department

Military Technical Institute

www.vti.mod.gov.rs

INTERLAMINAR STRESS ESTIMATION IN ISOGEOMETRIC COMPOSITE PLATES BASED ON THE HIGHER ORDER DEFORMATION THEORY

ognjen peković

Faculty of Mechanical Engineering, University of Belgrade, opekovic@mas.bg.ac.rs

SLOBODAN STUPAR

Faculty of Mechanical Engineering, University of Belgrade, sstupar@mas.bg.ac.rs

aleksandar simonoviĆ

Faculty of Mechanical Engineering, University of Belgrade, asimonovic@mas.bg.ac.rs

srđan trivković

Faculty of Mechanical Engineering, University of Belgrade, strivkovic@mas.bg.ac.rs

NIKOLA petrašinoviĆ

Faculty of mechanical engineering, University of Belgrade, npetrasinovic@mas.bg.ac.rs

Abstract: This research paper presents interlaminar stress recovery procedure for isogeometric laminated composite plate elements. The isogeometric formulation is based on NURBS (non-uniform rational B-splines) basis functions of varying degree and plate kinematics is based on third order shear deformation theory (TSDT) of Reddy. High continuity and variation diminishing property on NURBS basis make it possible for interlaminar transverse normal and shear stresses to be calculated directly from equilibrium equations. Numerical results with different element order are presented and obtained results are compared to analytical and conventional numerical results. Obtained results are in exelent agreement with 3D elasticity solution.

Keywords: Isogeometric analysis, Third order shear deformation theory, Interlaminar stress calculation.