Random Lattice Modeling of Fiber Reinforced Polymers


GFRP profiles have seen a growing interest among the scientific community as well as engineering practice over the last years. Their remarkable resistance/weight ratio is a desirable property in various applications, together with the extremely low thermal conductivity and their electromagnetic transparency. These profiles are produced by means of pultrusion: an automated, continuous manufacturing process which realizes constant section profiles, constituted of unidirectional fibers embedded in a polymeric matrix. The fibers provide the principal stiffness and strength characteristics, while the matrix transfers the forces while providing resistance to external agents.

In our research, we developed a Random Lattice Modeling approach for the simulation of fracture propagation in GFRP members under complex three-dimensional stress states. The stiffness and strength of each individual lattice element is calculated by means of the Tsai-Hill criterion, based on the angle the element forms with the direction of the fibers. The random arrangement of the nodal sites constituting the model guarantees a formal independence of the evaluated response on the mesh. 

Fracture propagation in a GFRP beam undergoing web-flange delamination


Comparison between numerical and experimental force-displacement curves