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Advisor(s)
Abstract(s)
Este trabalho apresenta o estudo das leis de propagação das velocidades de vibração
resultantes do uso de explosivo em diferentes maciços. Foram efectuados estudos para
três tipos de maciços diferentes, granito, quartzito e calcário. Efectuaram-se campanhas
de monitorização e registo dos dados em cada uma das situações. Caracterizando e
utilizando duas leis de propagação de velocidades no maciço, a de Johnson e Langefors,
calculou-se as suas variáveis por método estatístico de regressões lineares múltiplas. Com
a obtenção das variáveis fizeram-se estudos de previsão dos valores de vibração a obter
utilizando a carga explosiva aplicada nos desmontes. Através dos valores de vibração
obtidos em cada pega de fogo para cada tipo de maciço comparou-se quais das duas leis
apresentam o valor de velocidade de vibração menor desviado do real. Conforme ficou
verificado neste estudo, a equação de Langefors garante uma mais-valia da sua aplicação
na previsão das velocidades de vibração pois joga favoravelmente a nível da segurança
assim como apresenta um menor desvio face à equação de Johnson quando comparada
com o valor real de vibração obtido. Com isto o método de utilização de regressões
lineares múltiplas como cálculo dos efeitos vibratórios é extremamente vantajoso a nível
de prevenção de danos e cálculo de velocidades de vibração inferiores ao imposto pela
Norma.
This work presents a study of the propagation of vibration velocity resulting from the use of explosives in different rock masses. Were performed studies for three kinds of rock masses, such as granite, limestone and quartzite. There have been monitoring campaigns and data registry in each situations. Characterizing and using two different laws of propagation of vibration velocity, Johnson and Langefors, was calculated their variables by statistical method of multiple linear regression. After obtaining the variables were made studies to predict the vibration values when using the same explosive charges applied in the rounds. Through this vibration values obtained in each round for each kind of rock mass the two equations were compared with the real value and registered which one had the smaller deviation. As was verified in this study the Johnson equation appears to be better in the prediction of the vibration velocities because it had the small deviation and acts favorably at a security perspective. This method of using multiple linear regressions as calculation of the vibrations effects it’s extremely advantageous in a prevention level as well good predictor of vibration velocities smaller that the ones set in the Portuguese Standard.
This work presents a study of the propagation of vibration velocity resulting from the use of explosives in different rock masses. Were performed studies for three kinds of rock masses, such as granite, limestone and quartzite. There have been monitoring campaigns and data registry in each situations. Characterizing and using two different laws of propagation of vibration velocity, Johnson and Langefors, was calculated their variables by statistical method of multiple linear regression. After obtaining the variables were made studies to predict the vibration values when using the same explosive charges applied in the rounds. Through this vibration values obtained in each round for each kind of rock mass the two equations were compared with the real value and registered which one had the smaller deviation. As was verified in this study the Johnson equation appears to be better in the prediction of the vibration velocities because it had the small deviation and acts favorably at a security perspective. This method of using multiple linear regressions as calculation of the vibrations effects it’s extremely advantageous in a prevention level as well good predictor of vibration velocities smaller that the ones set in the Portuguese Standard.
Description
Keywords
Explosivos Vibrações Monitorização Prevenção NP 2074 Explosives Vibrations Monitoring Prevention
Citation
Publisher
Instituto Politécnico do Porto. Instituto Superior de Engenharia do Porto