Chaotic behaviour of seismic mechanisms: observation and models

• Author(s): Albino, A. ; Silva, Hugo Gonçalves ; Bezzeghoud, Mourad ; Caldeira, B. ; Borges, J.F. ; Tlemçani, M.
• Date: 2011
• Persistent ID: http://hdl.handle.net/10174/4381
• Origin: Repositório Científico da Universidade de Évora
• Subject(s): Seismic mechanisms; Chaos theory
• Document Type: Lecture
• Language: Portuguese

Description

Today, it is impractical work modelling the dynamics of failure, given the high complexity of the systems involved. As soon, it is important to identify models, as simples as possible, with qualitatively similar to the failures. The first model introducing is it the mechanical block-spring model, given by Burrigde-Knopoff [1]. In this work the subject was treated by experimental means. For that purpose it was developed and designed a mechanical system similar it that used in the numerical modulations, the so called earthquake machine (shown in Figure 1). We have equipped the springs of the machine with a set of force sensors connected to a data acquisition system (DAQ), linked in turn to a computer. The data recorded in the mechanical prototype consists of temporal series of tensions measured by the sensors that correspond to the sequence of tension accumulation and drop taking place in the springs. Data processing followed two distinct methodologies. The first treated the data according to the techniques used in seismology with field measurements. In the second methodology, we tried to use the series recorded in the context of chaos theories to investigate the behaviour of prototype.