The objective of this study is to promote the reduction of accidents in mining or other underground excavations, which in a greater percentage are caused by rockfall. On this occasion, an analysis of the technical and economic consequences of accidents is presented, then the factors with the highest incidence of accidents will be presented, as a result of the analysis of the information compiled from the sources. Due to the aforementioned, the primary sources have been used to collect the pertinent information on accidents that occurred in mining over more than 12 years. To meet the objectives of this publication, in addition, the existing literature has been reviewed and the costs of the accidents analyzed by Mg have been updated. Tomás Acero in 2004 and the social and business consequences. In general terms, the number of fatal accidents from 1970 to 2013 has been substantially reduce...

The cutters in general are the essential elements to crush, break and move to the rock during an excavation. In particular case of the tunnel boring machines (TBM), the disc cutters play a preponderant role since the attack to the rock takes place only by compression and rotation of the cutterhead that carries the cutters. The present research was carried out during the excavation of the Nº 4 headrace tunnel of the Yuncan hydroelectric project (Paucartambo II), located in Paucartambo district, Pasco province and department, where applied the MK 12 Atlas Copco Jarva TBM, that has 4.10 m cutterhead diameter provided with 27 disc cutters. From the pursuit of the cutters, its life in meters of excavated tunnel could be verified that, depends on its position in the mall pillow of a TBM, independent of the type of rock. It was possible to be demonstrated that the reinforcements (gauge cutters...

The tunnel boring machines (TBM) are continuous mining equipment designed for the excavation of circular tunnels until more than 15 m of diameter at the moment. The application of these machines in substitution of the conventional drilling and blasting method, is more and more frequent, including in our country, since from the first application in the Carhuaquero project (Chiclayo) at beginnings of the decade of 1980, spent almost 18 years for the following application in the Chimay project (1998-1999); soon between years 2000-2004 in hydroelectric project of Yuncan, they were applied to 2 TBM (only a year after the application in Chimay) and at the moment in the project it trasvase Elm trees, comes applying a TBM from the 2007. It demonstrates without a doubt, that the application of the TBMs is prominent in the present century. This article is based on the study made in the hydroelectr...

The present article is the result of the study of 20 mines in addition to not taken others in account in the present analysis, of which 18 are of anthracite, 1 semi bituminous and 1 of graphite; all these mines are located in the mountainous areas of the departments La Libertad, Ancash and Amazonas. The mining of the coal in the north of our country, is being handled mainly by unreliable people, being caused by the coal hoarders, without concerning the forms, methods nor conditions to them under which this substance is extracted. The ruling poverty in the carboniferous zones, has pushed the villagers to venture themselves and to risk in operating the carboniferous deposits, the majority of the cases without any technical manual nor the minimum conditions of safety. Some cases, the holders of the mining concessions, have entered agreement with the proprietary communities of superficial la...

Los cortadores en general son los elementos esenciales para triturar, fragmentar y desplazar a la roca durante una excavación. En el caso particular de las máquinas tuneleras tipo TBM, los cortadores de disco desempeñan una función preponderante dado que el ataque a la roca se produce únicamente por compresión y rotación del cabezal que porta dichos cortadores. El presente estudio se llevó a cabo durante la excavación del túnel de aducción N.º 4 del proyecto hidroeléctrico de Yuncán (Paucartambo II), ubicado en el distrito de Paucartambo, provincia y departamento de Pasco, donde se utilizó la TBM Atlas Copco Jarva MK 12 de 4,10 m de diámetro provisto con 27 cortadores de disco. A partir del seguimiento de los cortadores, se pudo verificar que su duración en metros de túnel excavado, depende de su posición en el cabezal de una TBM, independientemente del tipo de roca. S...

The tunnel boring machines (TBM) are continuous mining equipment designed for the excavation of circular tunnels until more than 15 m of diameter at the moment. The application of these machines in substitution of the conventional drilling and blasting method, is more and more frequent, including in our country, since from the first application in the Carhuaquero project (Chiclayo) at beginnings of the decade of 1980, spent almost 18 years for the following application in the Chimay project (1998-1999); soon between years 2000-2004 in hydroelectric project of Yuncan, they were applied to 2 TBM (only a year after the application in Chimay) and at the moment in the project it trasvase Elm trees, comes applying a TBM from the 2007. It demonstrates without a doubt, that the application of the TBMs is prominent in the present century. This article is based on the study made in the hydroelectr...

Este artículo es el resultado del estudio de 20 minas además de otras no tomadas en cuenta en el presente análisis, de las cuales 18 son de antracita, 1 semi bituminoso y 1 de grafito; todas estas minas están emplazadas en las serranías de los departamentos La Libertad, Ancash y amazonas. La minería del carbón en el norte de nuestro país está siendo manejada mayormente por informales, propiciada por los acopiadores de carbón, sin importarles las formas, los métodos, ni las condiciones en las que se extrae dicha sustancia. La pobreza reinante en las zonas carboníferas ha empujado a los lugareños a aventurarse y a arriesgarse en la explotación de los yacimientos carboníferos, en la mayoría de los casos sin ninguna dirección técnica ni las mínimas condiciones de seguridad. En algunos casos, los titulares de las concesiones mineras han entrado en convenio con las comunidad...

The objective of this study is to promote the reduction of accidents in mining or other underground excavations, which in a greater percentage are caused by rockfall. On this occasion, an analysis of the technical and economic consequences of accidents is presented, then the factors with the highest incidence of accidents will be presented, as a result of the analysis of the information compiled from the sources. Due to the aforementioned, the primary sources have been used to collect the pertinent information on accidents that occurred in mining over more than 12 years. To meet the objectives of this publication, in addition, the existing literature has been reviewed and the costs of the accidents analyzed by Mg have been updated. Tomás Acero in 2004 and the social and business consequences. In general terms, the number of fatal accidents from 1970 to 2013 has been substantially reduce...

n a previous study undertaken in march 2011 at Reliquias mine owned by Cía. Minera Castrovirreyna, it was demonstrated that hydrabolts in underground rock support, can bear greater load capacity than any of the three other rock bolts tested (Swellex, threaded rebar and split set). Thisadvantage of the hydrabolt motivated us to continue analyzing reasons for this and other variables. This study included compression tests on 18 high pressure water loaded hydrabolts, 18 water unloaded hydrabolts and one swellex. These tests were carried out at the material laboratory of the Pontificia Universidad Católica del Perú (PUCP). Maximum load on water loaded hydrabolt was 400KN, on the unloaded 50 KN and on the swellex bolts 59 KN. By analyzing the information gathered on these tests and in the previou...

To determine the mechanical and supporting properties of the plates for Hydrabolt rock bolts, compression and tensile tests have been performed. The tests were carried out in the Materials Laboratory of the Pontificia Universidad Católica del Perú (PUCP), from which it is concluded that the plates that undergo less compression deformation are the corner plates, which deform 14.01 mm for a maximum load of 41.56 KN, while the refined plates deform 25.10 mm for the maximum load of 40.56 KN. The plates that are most deformed by compression and traction are the refined plates. The corner ones are the least deformed, 28.91% to compression and 28.40% to central traction. Also, the plates that undergo greater deformation by the traction in the ears are the sharp plates. It is noteworthy that it is not convenient for the plates to be very rigid, since as the tension in the massif increases, it ...

Siendo el objetivo del presente estudio determinar la capacidad de sostenimiento de las placas para pernos de roca de mayor aplicación en el Perú, ha sido necesario realizar pruebas de compresión y tracción sobre cuatro tipos de placas: Python, Expanbol y dos tipos para los pernos Hydrabolt. Las pruebas se llevaron a cabo en el Laboratorio de Materiales de la PUCP, a partir de las cuales se concluye que las placas que sufren menor deformación global a la compresión son las Python, que se deforma 3,5 mm para una carga máxima de 109,68 KN, y las placas refiladas Hydrabolt son las que más se deforman, 25,10 mm para la carga máxima de 40,56 KN. Es de destacar que las placas Python tienen 0,7 mm mayor espesor que las Hydrabolt y son muy rígidas. Las placas que más se deforman por compresión y tracción son las Expanbol (586,44 %), seguido por las placas refiladas Hydrabolt. Las qu...

The objective of the present study is to identify factors to reduce accidents in mining or other underground excavations, caused by rockfall. To achieve this purpose, the fatal accidents that occurred from 2001 to 2011 were investigated in the prime sources, among others, MINEM, the Ministry of Labor and Employment Promotion and OSINERGMIN. From the information compiled and processed, the corresponding analysis was performed, thus identifying the following factors: a) Type of rock. 87% of fatal accidents occurred in type III and IV rocks. b) Type of support. 45.8% of fatal accidents occurred in unsupported areas and in areas sustained with wood, Split Set and Helical Bars occurred 45.85%. c) Type of work. 59% of fatal accidents occurred in hacking. d) Occupation. 53% of fatal accidents suffered drilling master and / or assistants. e) Work shift. 58% of fatal accidents occurred in day shi...

Rock mass support with rockbolts, is the greater application method in the rock excavation industry, because is necessary to carry out studies concerning this method of support. Among other things, there are parameters that directly influence on the anchor capacity of rockbolts, including incontrolable variables by man such as rock type, and variables that the man can control, like the bore hole diameter, which despite its great influence, little has been studied in this respect. The present study was conducted to determine the anchor capacity of Hydrabolt rockbolts, depending on the bond length and the bore hole diameter where they are installed. For that purpose, were conditioned to the site and the structure necessary to perform tests, simulating holes with tubes of 33, 36, 38 and 40 mm diameter making bond lengths of 1, 2, 3 and 4 foots. 64 tests were performed in San Marcos universi...

The support in underground excavations is essential to preserve the life and health of the workers, damage to the equipment and to have proper progress of the excavation. The most common Rock support sets are the rock bolts, temporary or definitive. Among temporary rock bolts, there are the Split sets, widespread around the world due to their ease of installation and cheaper. Split Sets, have the appearance of a tube with a 15 mm slot in its entire length, manufacturers and suppliers recommended 38 mm diameter of drill holes and depths according to their length. In this research, the ground and holes were simulated with a special table and steel tubes. Split Sets, were conditioned to make anchors of 1, 2, 3, and 4 feet of bond length. Prepared the simulator tubes and Split Sets were installed, after which, were performed the pull test of the 3 samples for each bond length to determine th...

Drilling and blasting in a mining operation is essential, since the efficiency of subsequent operations depends on it. However, blasting also has negative effects, which can be minimized by selecting explosives according to the rock type. The most commonly used explosive is the ANFO, whose power can be regulated, adding aluminum in different percentages depending on the rock type (according to Bieniawski or Barton classification). To carry out this study, blasting tests were carried out in the Condestable Mine, with ANFO aluminized up to 6% of powdered aluminum, carrying out the loading of drills with compressed air at 80 PSI of pressure and priming with cartridge emulsion, under these conditions, linear charge concentrations and total charge per hole were determined. From the analysis of 20 parameters, it is concluded that the optimal formulation of aluminized ANFO for primary blasting ...

The Drilling and Blasting (D & B) in tunneling, has been replaced by a variety of types and sizes of tunneling machines (TBMs) for technological progress, productivity demands and environmental control. This study is intended as a framework for selecting the most suitable system of excavation under a minimum length to justify its application. Both the TBM MK 12 and the D & B were studied in the headrace tunnel No. 4 Hydroelectric Project Yuncan. We show that for digging long tunnels, TBM have greater advantages than the D & B, plus the minimum disturbance to the remaining rock, speed of excavation, increased safety for personnel and equipment, lack of gas blasting, minor excavation area, among others.

In this article, we carry out an analysis of the energy reserve from coal, taking as a base the mines studied and the work carried out by the Geological Institute of Mining and Metalworking-INGEMMET, as an alternative to solve the energy crisis that Peru is already experiencing. The investigation began as a result of an article published in issue vol. 10 N ° 20 of the magazine of the FIGMMG Research Institute, on coal mining in northern Peru and the result of the study of more than 20 mines according to their classification, location, geology, mining and the prevailing social problem. According to the World Bank and other organizations, our country will continue to grow, therefore there will be greater energy demand, demand that cannot be covered with the scarce existing reserve; to which is added the gradual reduction of the flow of the rivers that operate the hydroelectric plants, due...

This research is focused on establishing the load capacity of the rockbolts commonly used in Peru based on their length. Initially, we aimed to perform the pull tests on granite blocks at San Marcos University Campus, they were carried out under real operating mining conditions, at Reliquias, Castrovirreyna Mining Company (Huancavelica) during March of the current year. The rockbolts tested were: Split Set, Threaded Rebars, Hydrabolt and Swellex, which were suitably conditioned to have an effective anchorage of 1 to 4 feet. The Split Set and Threaded Rebars were cut and delivered as per our request by PRODAC and Aceros Arequipa, respectively. Both, Hydrabolt and Swellex rockbolts, supplied by New Concept Mining and Atlas Copco, were piped around to allow the anchorage of the established lengths only. Fifty one tests were carried (11 Split Set, 17 Threaded Rebars, 12 Hydrabolts and 11 Swe...

La Perforación y Voladura (P y V) en túneles, ha sido reemplazada por una variedad de tipos y tamaños de máquinas de túneles (TBM) para el progreso tecnológico, las demandas de productividad y el control ambiental. Este estudio pretende ser un marco para seleccionar el sistema de excavación más adecuado con una longitud mínima para justificar su aplicación. Tanto el TBM MK 12 como el P y V fueron estudiados en el túnel de la carrera de cabezas No. 4 Proyecto Hidroeléctrico Yuncan. Demostramos que para excavar túneles largos, los TBM tienen mayores ventajas que los P y V, además de la mínima perturbación de la roca restante, la velocidad de excavación, una mayor seguridad para el personal y el equipo, la falta de voladuras de gas, área de excavación menor, entre otros.

En este articulo realizamos un análisis de la reserva energética a partir del carbón, tomando como base las minas estudiadas y los trabajos realizados por el Instituto Geologico Minero Metalùrgico-INGEMMET, como una alternativa para resolver la crisis energética que ya vive el Perú. La investigación se inició a raiz de un articulo publicado en la edición vol. 10 N° 20 de la revista del Instituto de Investigaciòn de la FIGMMG, sobre la minería del carbón en el norte del Perú y el resultado del estudio de más de 20 minas según su clasificación, ubicación, geología, minería y el problema social reinante. Según el Banco Mundial y otros organismos, nuestro país seguirá creciendo, por ende habrá mayor demanda energética, demanda que no podrá ser cubierta con la escasa reserva existente; al cual se suma la reducción paulatina del caudal de los ríos que accionan las h...