Applications for porous fibrous materials range from electrochemical substrates to web reinforcement in polymeric composite materials. The details of local load transfer are studied in a class of cost-effective, stochastic fibrous networks used in battery applications. The connectivity of these materials is quantitatively related to modulus and strength, and detailed results of different simulations approaches in approximating material construction are discussed. In Part II, we focus on the consequences of various microscale assumptions concerning bonding, beam type, failure mode and simulation scale on effective moduli and peak loads. We show that the effects of scale are important even in a tight range of window sizes (one-tenth to ten times the staple length), especially as compared to the relative insensitivity of conductivity to scale, when only bulk conduction is considered. We also discuss issues of connectivity at the scale of the porous material rather than element-by-element. This work points toward use of simple constructions to model complex behavior, and may ultimately provide insight into modeling of a large class of porous materials. [S0094-4289(00)01604-2]

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