Monitoração experimental e modelagem numérica sobre a resposta estrutural dinâmica de passarelas de pedestres.

• Autor(a) principal: Debona, Gilvan Lunz
• Data de Publicação: 2016
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UERJ
• Texto Completo: http://www.bdtd.uerj.br/handle/1/11473
• topic: Pedestrian footbridge; Dynamic analysis; Pedestrian-footbridge interaction; Human comfort; Excessive vibration; Engenharia civil; Passarelas para pedestre; Análise dinâmica; Interação pedestre-passarela; Conforto humano; Vibrações; CNPQ::ENGENHARIAS::ENGENHARIA CIVIL

The study of the dynamic behavior of pedestrian footbridges on the part of civil engineers is not considered like a regular procedure in structural design offices, especially with regard to attend the serviceability limit states (human comfort). However, these structural models need to present an appropriate dynamic behavior, free of the risks inherent to the presence of excessive vibration or human discomfort. Thus, aiming to contribute to the study of this research topic, the main objective of this work concerns to the experimental monitoring and numerical modelling of the structural dynamic response of pedestrian footbridges, based on the consideration of the pedestrian-structure dynamic interaction. This way, the investigated structural model is associated with a reinforced concrete pedestrian footbridge located in the Faculty of Engineering (FEN) on the campus of the State University of Rio de Janeiro (UERJ). The structural system is simply supported with a 24.4 m span, currently used for pedestrian crossing. Initially, the modal analysis of the footbridge was conducted based on the dynamic experimental monitoring through the use of accelerometers on the structure and pedestrians, considering a device used for data acquisition via laser vibrometry (PDV-100: Portable Digital Vibrometer) and also considering another system for the measurement of vibrations (Shaker). With respect to the free vibration tests two techniques were applied: SIMO (Single Input Multiple Output) and SISO (Single Input Single Output). Regarding the SIMO technique, an excitation force is applied on the structure (input) and the structural dynamic response (output) is obtained simultaneously in several points of the model. With regard to the SISO technique, the force is applied on the structure and the dynamic response is obtained individually at each point of the system, considering the variation in the position of the excitation force (input) and the sensor measurement (output). With reference to the forced vibration tests the dynamic loads coming from the pedestrians were used, considering two types of excitations: the first is intended to excite the footbridge based on the control of the pedestrian step and the human body movement, using a metronome and accelerometers installed on the structural model and pedestrians; the second is related to the random walk of the people on the structural system, such as commonly occurs during the service life of the structure. Finally, a finite element model was developed, incorporating the effect of the pedestrian-structure dynamic interaction, based on the use of biodynamic models representative of the pedestrians. This numerical model was used for the calibration of the results obtained based on the footbridge experimental monitoring. Then, the structural dynamic response of the structural model was evaluated and human comfort levels were compared to several criteria established in the standards and design recommendations.