LAUSR

Due to urbanization, construction of civil structures and infrastructure within complex rocks such as conglomerate and mélange is inevitable. Such rocks normally represent very heterogeneous structures. Obtaining representative undisturbed sample of these rocks is cumbersome and the estimation of their geological and geomechanical parameters is, therefore, very challenging. In the literature, such heterogeneous rocks, which are an assortment of rock blocks surrounded by a weaker fine matrix, are called block in matrix rocks (bimrocks). In the present study, the function of fractal dimension, volumetric block proportion (VBP), and largest block size in the bimrock’s deformation modulus are investigated through fabricating large-scale physical specimens and performing laboratory tests. Outcomes of the study revealed that the deformation modulus of physical samples increases with the increase of VBP and the reduction of the fractal dimension. The deformation modulus of physical specimens including coarse aggregate is also more than that of fine aggregates and the difference between them is enhanced with the reduction of the fractal dimension. A new factor called block contact coefficient is introduced to explain the variations in the deformation modulus. Results of the analysis also show that the strength reduction rate in the post-peak region increases with enhancing VBP, and it is less affected by fractal dimension and the largest block size.