The solution of non-linear problems in mechanics is usually a complex task.
It requires much more e¤orts in analytical and numerical part of the solution
(pure analytical solution for most problems is not possible at all). This work
comprises solutions of several non-linear problems involving cracks growth and
In the rst part of the work experimental procedure was elaborated in order
to nd delamination properties of the unidirectional and translaminar-reinforced
composites. Bridging law, which can be calculated from experimental data, is
found to be important material property. Simple numerical procedure, which
uses previously found bridging law, is proposed in order to simulate crack growth
in composite laminates.
In second part the three-dimensional mathematical model for analysis of
Hot Dry Rock geothermal reservoirs is presented. By utilizing Laplace integral
transform and Green s function the solution is reduced to integral equation
over the surface of the fracture, which eliminates the need for discretizing the
unbounded 3D reservoir. Using presented model temperature and thermally
induced stresses can be found anywhere in the reservoir at any time, which
makes this model quite e¢ cient in geothermal reservoirs analysis.