9301267, PI-Einstein: The objectives of this research are to investigate experimentally and theoretically the coalescence between non overlapping pre existing discontinuities. Theoretical work will involve both a quasi continuum as well as a discrete fracture propagation model. The experimental and theoretical research are closely interrelated by using the experimentally validated analytical and numerical models in parametric studies to extend the experimental investigations. It is intended to gain a basic understanding od coalescence fracturing and to develop predictive procedures by considering the effect of a variety of material properties, of the geometry of the pre existing discontinuities and of the stress field.
