**Journal of Theoretical**

and Applied Mechanics

and Applied Mechanics

**57**, 1, pp. 27-35, Warsaw 2019

DOI: 10.15632/jtam-pl.57.1.27

### A stereological ubiquitiformal softening model for concrete

crete under quasi-static uniaxial tensile loadings is presented in this paper. In the model,

both the damage evaluation process of fracture cross-sections and their distribution along

the specimens axis are taken into account. The numerical results of a certain kind of full

grade concrete made of crushed coarse aggregate are found to be in good agreement with

the experimental data. Moreover, an experiental relation between the lower bound to the

scale invariance of concrete and its tensile strength is also obtained by data fitting of the

experimental data, which provides an effective approach to determine the lower bound to

scale invariance of concrete.

*Keywords*: ubiquitiform, fractal, concrete, softening curve

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