During granular carbon-carbon composites manufacturing, the binder (a pitch) is carbonized while surrounded by solid filler particles. This geometrical limitation imposed on the carbonization medium results in constraints responsible for textural modifications of the pitch-based coke. We studied the consequences of geometrical limitation on pitch carbonization, and also the influence of the as-formed composites multiscale organization on their mechanical properties and carboxyreactivity behavior. The micrometer scale is relevant to understand composite reactivity while the submillimeter scale enables a better comprehension of the mechanical properties. (C) 2002 Elsevier Science B.V. All rights reserved.