Hardening matrix defined

The experimental curves stress-draw ratio (o - A) for SBR and nanocomposite SBR-2 are presented in Fig. A. 1 [ 11]. As one can see, the curves a - A for these materials differ significantly even by exterior appearance one can visually affirmed, that nanocomposite has higher Young s modulus E and much more strong strain hardening (i.e., modulus at large strains) than matrix rubber SBR. For these curves theoretical description the authors of Ref [10] used two approaches classical [3] and fractal [7] ones. The first fi om them supposes the relation between a and A, defined by the equation [3] ... 

Bone tissue can be defined as a composite material. Collagen, one of the most common proteins of the body, represents almost 90% of the bone organic component and endows elasticity and impact resistance to the tissue. The second component, the inorganic one, stiffens and hardens the organic matrix and is formd in form of crystals from the hydroxyapatite mineral family [1-4]. 

Mechanical assumptions. Aggregates are assumed to be purely elastic whereas the bulk matrix of mortar and the transition zone follow the Lubliner s damaged plasticity law. CEB-FIP model is used to define ID tensile and compressive behaviors [3]. This model depends mainly on a single input the compressive strength of the material. In this study, an ordinary concrete with a water-to-cement ratio of 0.4 is considered. After [2], the capillary porosity of the corresponding hardened cement paste with a degree of hydration of 0.83 is 0.176. However the introduction of a granular skeleton modifies the bulk matrix and decreases its porosity. To take into account this phenomenon, [4] proposed to link the porosity of the various zones of the matrix by Eq.l. 

We focus on mineral foams defined as porous stracture obtained with a mineral matrix, starting from slurry or paste. Cellular concrete [1] is an example with quite good compromises. Its stracture presents cells size ranging from 0.2 to 2 mm with a wall thickness around 0.1 mm. Foam is obtained at fresh state, before the thermally activated hardening of the mineral binder. 

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