Tunnels have recently become a very interesting case of study when special conditions like fire or blasting are taken into account. An accurate treatment of these special conditions is not usually familiar to many structural designers and this work tries to provide a useful tool for the assessment of structural elements under blasting phenomena (or general vibrations). This book focuses on the analysis of circular plates made in traditional reinforced concrete and fibre-reinforced concrete. These materials are commonly used in the design of tunnels and many other structures on which this work can be applied. Two cases of interest are thoroughly discussed and solved: a simply supported plate and a plate resting on a Winkler-type soil. The aim of these analyses is the development of pressure-impulse diagrams for several pulse shapes. Pressure-impulse diagrams represent a very useful graphical method for the preliminary assessment of structural components subjected to blast loadings. In fact, according to the conditions of a plate sample, it is possible to know immediately if the structure will be damaged, just placing a point in the pressure-impulse diagram.