Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-07-20T13:16:55Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) dissertação final - andrevhity - cd - bdtd.pdf: 7048267 bytes, checksum: 0a2bd5941283791f51f6e1671f68b201 (MD5) / Made available in DSpace on 2016-07-20T13:16:55Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) dissertação final - andrevhity - cd - bdtd.pdf: 7048267 bytes, checksum: 0a2bd5941283791f51f6e1671f68b201 (MD5) Previous issue date: 2015-12-09 / CAPEs / As operações unitárias em pedreiras tais como: desmonte, perfuração e britagem são imprescindíveis, e são etapas que exige controle na produção e que demandam quantidade razoável de elementos essenciais para a produção e que desgastam rapidamente, por essa razão estes procedimentos necessitam de análise e acompanhamento contínuo. Uma maneira de otimizar a produção em pedreiras e garantir com isso melhor controle na produção é realizando uma análise estrutural mais detalhada do maciço rochoso e determinando previamente as suas descontinuidades, seu estágio de deformação e o seu comportamento mediante a aplicação de explosivos. Um modelo matemático pode ser aplicado para simular a fragmentação do desmonte de rochas e posteriormente adequar a granulometria proveniente da mina (ROM – Run of Mine) obtendo uma melhoria no desempenho do desmonte e otimizando a britagem com o aumento da eficiência/produtividade. O modelo consiste nas equações propostas de Kuznetsov (1973), Cunningham (1983), Lilly (1986) e Tidman e Rosin-Rammler (1933), e são utilizadas para maior interação entre explosivo e rocha. / The unit operations in quarries such as blasting, drilling and crushing are essential, and are steps that require control in production and demand reasonable amount of essential elements for the production and wear out quickly, therefore these procedures require analysis and monitoring continuous. One way to optimize the production in quarries and thereby ensure better control of production, making it a more detailed structural analysis of the rock mass and previously determining the discontinuities, its deformation stage and its behavior upon the application of explosives. A mathematical model can be applied to simulate the rock blasting fragmentation and then tailor the grain size from the mine (ROM - Run of Mine) obtaining an improvement in the performance of dismantling and optimizing crushing with increasing efficiency and productivity. The model consists of the equations proposed Kuznetsov (1973), Cunningham (1983), Lilly (1986) and Rosin - Rammler and Tidman (1933), and are used for higher interaction between explosive and rock.

This thesis has been conducted for the Luleå University of Technology (LTU), Sweden as part of an inter-university collaboration between LTU and the Montanuniversität Leoben (MUL), Austria.   The project has included three master thesis works, all investigating some aspects of the effects of jointing on fragmentation through small scale tests.   The topic of this thesis has been to develop a method for representing/introducing artificial joint planes into concrete blocks and subsequently manufacture a number of specimens with different joint sets for testing, using block dimensions previously used at MUL. The method for manufacturing the jointed test specimens, developed by the author at LTU, has been evaluated through blasting and fragmentation analysis. Comparison of the different produced joint sets has been done to assess the influence of jointing on fragmentation.   A total of 10 magnetic concrete blocks were produced and evaluated. The 10 blocks had an average density of 2485 ± 41 kg/m3 (mean ± standard deviation). Eight of the 10 blocks contained joint sets (JS) with different characteristics, while two blocks were un-jointed reference blocks. A total of four different joint sets were developed.   The four joint sets had the following properties; JS1: joint spacing 95 mm, strike/dip equal to 0/90°, JS2: joint spacing 47.5 mm, strike/dip equal to 0/90°, JS3: joint spacing 47.5 mm, strike/dip equal to 60°/90° and JS4: joint spacing 89 mm, strike/dip equal to 0/70°.   The produced joints have proven to behave as desired, i.e. being able to reflect incident waves and to stop some incident cracks.   It has been found that there is a strong indication of jointed blocks producing a finer median fragmentation size (x50) than that of the reference blocks. This means that by introducing joint sets into the test specimens the degree of fragmentation by blasting has been increased. This was predicted by the Kuz-Ram model.   Each of the 28 blasted rows has been sieved and analysed. All the data has been fitted to the three parameter Swebrec function, producing an average coefficient of determination (an R-square value) of 0.9946 ± 0.0064.

Este trabajo de investigación busca mejorar la estimación de la fragmentación de roca volada en minería a cielo abierto, específicamente en la empresa Minera Aruntani S.A.C. Unidad Arasi. La investigación se lleva a cabo mediante una reestructuración a la ecuación de predicción del tamaño de rocas, Kuz-Ram, modelo tradicional, cambiando el coeficiente de tierra, permitiendo disminuir los márgenes de error tomando en consideración aspectos relevantes del diseño como los parámetros geológicos, así como parámetros de perforación y voladura. Para efectuar dicho logro, se planteó una función objetivo y su posterior solución mediante el método iterativo de Newton-Raphson desarrollado en un entorno del software Matlab. El pertinente planteamiento y desarrollo permitió obtener un nuevo valor para el coeficiente de tierra con el cual se logra disminuir los porcentajes de error en la estimación de fragmentación de 40%, con el método tradicional, a un 8% en promedio logrando así una mejora considerable. / This research work seeks to improve the prediction of the fragmentation of blasted rock in open pit mining, specifically in the company Minera Aruntani S.A.C. Arasi unit. The research is carried out through a modification to the Kuz-Ram fragmentation estimation model, a traditional model, changing the land coefficient, allowing to reduce the margins of error taking into consideration relevant aspects of the design such as geological parameters, as well as parameters of drilling and blasting. To carry out this achievement, an objective function was proposed and its subsequent solution by means of the iterative Newton-Raphson method developed in a Matlab software environment. The pertinent approach and development allowed obtaining a new value for the land coefficient with which it is possible to reduce the error percentages in the fragmentation estimation from 40%, with the traditional method, to 8% on average, achieving a considerable improvement. / Tesis