W.J. BERANEK and G.J. HOBBELMAN Delft University of Technology

Lattice models provide the opportunity to introduce the structure of a brittle material into its mechanical behaviour. The advantages and disadvantage!: of regular and irregular lattice models are discussed. In the paper regular lattices are applied throughout. To improve unsatisfactory behaviour in certain directions, several adjustments have been worked out regarding the failure criterion and the post peak behaviour. This has primarily been done for the ideal brittle material and adaptations are shown which are required for masonry walls.