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In this study, the investigating of sawability and abrasivity of Khalkhal and Azarshahr travertine were carried out in order to the planning of a new plant. To achieve the goal, rock samples were collected from the mines and some mineralogical, physical and mechanical properties of rocks were determined in the laboratory. The sawability was determined by using some empirical methods based on Schmidt hammer value, Tensile Strength, Uniaxial Compressive Strength and P-wave velocity and abrasivity of rocks were inves...

The First step in analysis of slope stability in open pit mines is punctual definition of rock mass characteristics. Several rock mass classification systems have been presented so far in the area of geomechanics. One of the most widely used rock mass classification systems are the geomechanics classification (RMR) by Bieniawiski. The RMR classification is based on the definition of classic membership functions. So characterization of rock masses and determination of their strength may involve some uncertainties d...

Characterization of rock masses is one of the fundamental aspects of rock engineering. Particularly, as a rock mass characteristic, determination of the strength of jointed rock masses is difficult since the size of representative specimens including discontinuities is too large for laboratory testing. This problem can be overcome by using the Hoek– Brown empirical failure criterion in conjunction with the Geological Strength Index (GSI) classification system. However, characterization of rock masses and determi...

In this paper, the relationship between p-wave velocity and the most important strength properties of rock material has been studied. During this research eight various types of rocks from north-west of Iran have been tested view pointed of uniaxial compression strength (UCS), tensile strength (Brazilian test) and elastic modulus. Regression analyses between above parameters and p-wave velocity reveals that there is a mathematical relationship with exponential equation (R2= 0.8597) between p-wave velocity and unia...

Roof falls continue to be one of the greatest hazards faced by underground coal miners. For preventing unpredictable hazards and losses due to roof falls, assessment of roof rock behaviour in coal mines plays an assential role in ground control issue. However, based on the intensive reserches in this area, various parameters influence the roof rock behaviour of the stratified rock mass. One of them, which is extremely important to coal mine ground control, is moisture sensitivity. Many coal seams have immediate ro...

Blast pattern design has direct influence on the time consumption and construction cost of drilling and blasting of tunnels. Tunnel blasting is more complicated operation than open pit blasting because the only free surface that initial breakage can take place toward is the tunnel face. The most important operation in the tunnel blasting procedure is to create an opening in the face with the intention of develop another free surface in the rock. This is the function of the cut holes. The cuts can be classified in ...

Most of water resources in Iran are flowing in the west, south-west, north districts of country and, on the other hand, providing of water the central districts of Iran, for a long term, had been a critical problem to Iran water industry since long ago. Accordingly, many water transferring projects have been proposed between different zones to remove this problem. Transferring water from of Dez river to central districts of Iran is one of these projects that water transfer tunnel from Anvaj river to Qomrud is its ...

Coal is an important energy resource in world. Coal mine exploitation with nonmechanized methods, need expert labors and with out them, mining process will be deranged so the labors and their safety is really important. In many industrial countries the accidents are the most important cause of person’s death. According to I.L.O (International Labor Organization) reports 120,000,000 accidents occur per year and 210,000 people die in these accidents. It means more than 500 people per day. In order to decreasing th...

Since long term production scheduling deals with movement of ore and waste during the life of a mine, it has a significant effect on the cash flow of a mining operation. Therefore, mine planners often seek to optimize the production schedule with respect to a given criterion. The most commonly used criterion in long term scheduling optimization is to maximize net present value (NPV). The process involves sequencing of ore blocks or parcels to be mined in each period over the life of the mine subject to precedence ...

For opening of blocks No. 7 \& 8 of Golbini mine in Bauxite Jajarm region (Northern- Khorasan province, Iran) a tunnel is excavated with horse shoes shape with 800 m length. In this paper firstly, the tunnel section was modeled by FLAC2D software and secondly the stability analysis were studied. Then a composition of shotcrete and steel frame was offered. To reach an appropriate safety factor the shotcrete with 20 cm thickness which utilized with steel bars IPE-140, IPE-160 and IPE-180 established and amounts of s...

The optimum pit limit design can be defined as determining the ultimate or final mining limits of ore deposit with maximum value or profit which is obtained from its extraction. Heuristic optimization techniques have been one set of the most widely used methods for ultimate pit limit analysis because of their rapid execution speed and easy conceptualization. This paper considers a heuristic technique, known as 3D moving cone to find the optimum pit limit of Sangan iron ore deposit in Iran. To evaluate the results ...