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38 D T Ind. data 22(2), 2019 ANALYSIS AND ASSESSMENT OF CONVENTION AL AND PL ATFORM-BASED MINING METHODS ADOPTED AT THE UNACEM S. A. A. COMP ANY LIMESTONE Q UARRY do de plataformas secuenciales en el PIT II can-tera negro africano proyecto de rocas y minerales industriales (R. M. I.)-Calquipa S. A. C., states …
The evolution characteristics of rock fracturing in presplit blasts are generally affected by in situ stress resulting from tectonic forces in the Earth's crust and from gravity. In this study, rock fracturing under coupled static stress and presplit blasting conditions is comprehensively investigated by combining experimental, theoretical and …
Limestone is a fundamental raw material in various industrial sectors. It is formed due to biochemical precipitation of calcium carbonate, and further compaction over long periods of time.
For example, a highly jointed limestone quarry with 35-ft. benches needs to be presplit to provide a smooth final wall near a structure such as a crusher. The drill rig is capable of drilling a 3-in. hole. The question then becomes, what blasthole spacing should be used and what would be the powder load? ... Using this method, even weak ...
The most widely adopted method of limestone mining is through opencast pits with bench formation. ... It was found that water samples analysed from the vicinity of limestone quarry and cement ...
Presplit blasting involves drilling a single row of holes along the back of the final excavation zone [3]. Unlike smooth wall blasting, the presplit holes are fired on the first delay of the production blast. The presplit technique is the most commonly used controlled blasting technique for surface operations. 3. Methods3.1. Line drilling
Presplit blasting is a useful method for many impacts in the drilling and blasting spaces. With this method, a curtain of fracture is created by firing the lightly charged holes before …
Part 1 of Pit & Quarry's four-part "Overcoming Oversize" series focuses on the location and treatment of oversize in the stemming zone. ... Stab holes can be a great tool in some situations – if, for example, we have a presplit drilled on an angle and we have a large amount of rock between the crest of the presplit and the buffer holes ...
Field description of the study area. The National Cement Factory in Ethiopia, a major cement producer, operates a limestone quarry using open-pit mining with a multi-bench system.
Improving Drilling and Blasting Programms at Al Jazi Limestone Quarry. ... Figure 12 shows an example of a cut slope that used presplit basting methods which left visible half casts in the slope face. Presplit blasting requires relatively small drill holes, between 5 to 10 cm (2 to 4 in) in diameter because its goal is to create discrete ...
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Face mapping and Point Load Test (PLT) were used to characterize the rock at the RP3 Lafarge Limestone Quarry. The explosives parameters and blast design used in this study are the …
In order to explore differences of presplit and smooth blasting, the comparisons of the two control techniques have been conducted by some scholars from several perspectives. Lu et al. compared the difference of presplit and smooth blasting from the difficulty of crack forming during the excavation of underground tunnel. The results indicated ...
For example, Kesinal et al. discussed the influence of blast-induced acceleration on slope stability at a limestone quarry by field monitoring and theoretical analysis (Kesimal et al., 2008); Thote and Venkat experimentally investigated the slope damages due to blast loadings of different frequencies and vibration velocities (Thote …
Blasting is a vital operation in industries such as mining, construction, and quarrying. It involves the use of chemical explosives to break down rocks and other hard materials for various purposes, including the extraction of minerals and the construction of infrastructure [1,2,3,4,5].However, conventional blasting practices have significant …
This study focuses on analyzing the stability of existing quarry cut slopes, estimating their final depth, and conducting a parametric study of geometric profiles …
Using the presplit method, clean vertical walls up to 70 ft in height were obtained in moderately dipping, though complexly sheared and jointed argillaceous limestone. As the work pro gressed, the presplit program was modified to meet the varying geologic conditions and job requirements. This work was done on a production basis.
Presplit blasting involves drilling a single row of holes along the back of the final excavation zone [3]. Unlike smooth wall blasting, the presplit holes are fired on the …
1. Introduction. Mining provides important raw materials for national economic development and the progress of human civilization and is a mainstay industry of many countries and regions [].Moreover, open-pit mining is generally preferred in mining operations due to its applicability in all operable areas of exposed rock, minimum …
Dewatering may be difficult or ineffective, so in cases where the ground remains saturated, please discuss the impact of high hydraulic pressures from the production blasting and what can be done to assure that those pressures do not pre-dilate the final wall when trim blasting or dilate the final wall past the presplit when presplit …
Combining the characteristics of this quarry with a summary of previous studies on environmental restoration work, this paper proposes a novel and systematic method that was comprehensively ...
Presplit blasting is a useful method for many impacts in the drilling and blasting spaces. With this method, a curtain of fracture is created by firing the lightly charged holes before the main or primary production blast holes. Along the perimeter of the last excavation, holes are drilled consecutively [7]. ...
Environmental Impact Assessment (EIA) is a prominent technology to assess the environmental changes in the open cast Limestone mining region. However, traditional EIA methods and Limestone deposit identification involves time consuming, cost effective and manpower requirements. We cope-up these problem and incorporated with different …
The first study that was completed was calculating the explosive load for precision presplitting based on the rocks compressive strength (Konya & Konya, Precision Presplit Design, 2015). The compressive strength of the rock is the ability of the rock to withstand compression. The way a precision presplit functions is: 1.
Pre-splitting can be defined as 'a technique using lightly charged, closely spaced holes to induce a fracture plane along a required design profile, which isolates …
To understand differences of smooth and presplit blasting for the excavation of rock wells, two field experiments using these two techniques are implemented at the same test site, respectively.
Presplit drilling and blasting are frequent excavation methods used in the mining and construction industries, but they can be challenging to implement which can also lead to inconsistent results.
The Cuckoo Search (CS) is a very fast and efficient global optimization method to locating the slip surface which carried out by iteration. However, the Grid Search (conventional method) method in ...
The relocated quarry will be capable of providing security of supply for about 40 years and will need to deliver around two million tons of limestone to Ulco each year. According to Gavin Venter, manager Saldanha and Strategic Projects at AfriSam, the enabling infrastructure for this quarry has been significant.
