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...

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 anchor bolt or tendon is an effective, simple and quick installation and lower cost support device than any of the known support methods. There is a wide variety of bolts and tendons to fix the rock, ranging from wooden bolts to iron pipe bolts and smooth and corrugated steel rods with anchors that are generally of two kinds: point and longitudinal. The most widespread at present is the longitudinal anchor, of which the cement grout anchor is used more for its ease of application and low cost. The cement grout, however, has deficiencies for its application in anchorage due to its low resistance to tension and shear, volumetric contraction when setting, low adherence capacity, long setting period, low resistance to corrosion, humidity , to weathering and vibrations. The alternative is resin, but its high cost has practically eliminated its use as an anchor for bolts and tendons, espec...

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...

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 anchor bolt or tendon is an effective, simple and quick installation and lower cost support device than any of the known support methods. There is a wide variety of bolts and tendons to fix the rock, ranging from wooden bolts to iron pipe bolts and smooth and corrugated steel rods with anchors that are generally of two kinds: point and longitudinal. The most widespread at present is the longitudinal anchor, of which the cement grout anchor is used more for its ease of application and low cost. The cement grout, however, has deficiencies for its application in anchorage due to its low resistance to tension and shear, volumetric contraction when setting, low adherence capacity, long setting period, low resistance to corrosion, humidity , to weathering and vibrations. The alternative is resin, but its high cost has practically eliminated its use as an anchor for bolts and tendons, espec...