ABSTRACT
Gothic construction was based on pre-scientific criteria about masonry, based on the professional praxis of the master builders. Master builders of the middle age assign a concept to each kind of masonry depending to the material and shape of the stone. The use of non-invasive techniques enables to obtain data from built elements without altering them. The technique of Ground Penetrating Radar (GPR), has been usually applied for the characterization of the subsoil, but nowadays is also a great tool for surveying the inner composition of masonry structures. Initial studies were based on historical documentation and the stereotomy of the masonry, and determined that the pillars were solid and without infill. GPR data are of bipolar character, GPR data are the reflexions of the energy that is moving between two ways of propagation. The representation of this data reflects different ways of expressing the same information.
