a new model is proposed for two-dimensional simulation of the concrete fracture in compression. the model generated by using the voronoi diagram method and with considering random shape and distribution of full graded aggregates at the mesoscopic level. the aggregates modeled by combining irregular polygons, which then is placed into the concrete with no intersection between them. by this new m...

We study the geometrical characteristic of quasistatic fractures in brittle media, using iterated conformal maps to determine the evolution of the fracture pattern. This method allows an efficient and accurate solution of the Lamé equations without resorting to lattice models. Typical fracture patterns exhibit increased ramification due to the increase of the stress at the tips. We find the rou...

Parallel programs mainly diier from sequential ones in that they include geometrical aspects involved by the hardware architecture. We present in this paper the Pei formalism, which enables to take into account both the geometrical and functional aspects of programs. It provides a reenement calculus mainly used to transform the geometrical characteristics of parallel programs, and we show how i...