Dynamic actions introduced by the vibrations of the bells on the belfry (Spanish text)

This thesis studies the influence of the dynamic actions induced when the bells swinging on the structure of the belfry. In the first chapter a historical journey is made with the purpose of outlining when it begin to be used the bells, when these it begins to turn and when big models they are built; It contains a brief study about the history of the belltowers. In the second chapter it studies about the different forms of swinging bell existent in the different countries relating the studies and conclusions at this time about the different types of swinging bell and their influence on their structure. In the third chapter the state of the art is presented, the different studies published until the present time about the dynamic effect introduced by bells. All the technical studies here picked up they make reference to the Central European and English systems. In the fourth chapter the methods and results are exposed to develop and to determine centres of gravity, weight and inertia of bells. The study concludes with results of more than fifty bells of our environment. The fifth chapter presents the study of the differential equation of the movement of a bell, studying the horizontal and vertical forces of inertia introduced on its supports by the bells when turning. Results of usual speeds of turn are presented. It presents the vertical and horizontal forces introduced by bells of our environment on their supports. In this chapter they are distinguished the frequencies of turn of bells with engine of impulses, manual systems and engine of “continuous swinging”. The sixth chapter develops the interaction of swinging of bells on its structure amble. It presents the necessity to rehearse the buildings that sustain them dynamically. The methodology is presented to carry out to evaluate this influence. In this chapter it is studied the real case of the tower of San Pedro's Apostle Parochial Church attentively in Cinctorres (Castellón). In the seventh chapter it proceeds to the study of three real cases: The belfry of the Church of Nuestra Sra. del Carmen in Valencia, the bell tower of the Parochial Church of Bonrepós i Mirambell (Valencia) and the bell tower of San Pedro's Apostle Parochial Church in Agost (Alicante). In the three they have thought about processes to rehearse the structures dynamically, numeric models of finite elements have been carried out and these have been adjusted through the rehearsals carried out on the structures. The conclusions are presented and obtained for each one of these towers on the influence of swinging of their respective bells; it has been necessary, therefore, to determine the mechanical characteristics of the bells in each bell tower. In the last chapter the obtained conclusions of this study and the future investigation lines are presented for this field.