A 2D p-version LSFEF for laminated composites incorporating laminate physics

Conference · Thu Dec 31 04:00:00 EST 1998

OSTI ID:357772

Nayak, H V; Surana, K S ^[1]

---

1. Univ. of Kansas, Lawrence, KS (United States). Dept. of Mechanical Engineering

This paper presents a 2D p-version least squares finite element formulation for laminated composites incorporating the physics of laminated behavior. At the interface between two laminas of dissimilar materials the authors have continuity of displacements u, v, stresses {sigma}{sub yy}, {tau}{sub xy}, and strain {var_epsilon}{sub xx}, while the stress {sigma}{sub xx} and the strains {var_epsilon}{sub yy} and {gamma}{sub xy} are discontinuous. Thus, a finite element formulation, incorporating the physics of laminate behavior, would require interpolation of u, v, {var_epsilon}{sub xx}, {sigma}{sub yy}, {tau}{sub xy} instead of u, v {sigma}{sub xx}, {sigma}{sub yy} and {tau}{sub xy} which is generally the case in most LSFE formulations. In the p-version LSFEF presented here, the authors interpolate u, v (primary variables) and {var_epsilon}{sub xx}, {sigma}{sub yy}, {tau}{sub xy} (auxiliary variables) using equal order p-version C{sup 0} interpolations which would ensure interlamina continuity of these components. When the mating lamina properties are different, interlamina discontinuity of {sigma}{sub xx}, {var_epsilon}{sub yy} and {gamma}{sub xy} is automatically generated due to dissimilar material properties of the laminas. In this formulation interlamina jumps in {sigma}{sub xx}, {var_epsilon}{sub yy} and {gamma}{sub xy} do not constitute singularities, hence mesh refinements and higher p-levels are not needed in the vicinity of inter-lamina boundaries.

• OSTI ID: 357772
• Report Number(s): CONF-980213--
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COMPOSITE MATERIALS
FINITE ELEMENT METHOD
INTERFACES
LAYERS
STRAINS
STRESS ANALYSIS
STRESSES
TWO-DIMENSIONAL CALCULATIONS