3.1 Pit Wall Stability A safe and stable wall(pit) is of importance and vital to all aspects of mining operations especially blasting. Ensuring a stable pit wall requires a fair knowledge of geology, ground water conditions, slope and blast design. The strength of the rock mass under tensile, shear and compressional loading will determine the overall stability of a pit wall. A pit whose wall’s stability is not given utmost priority experiences backbreak or overbreak and hence has a high chance of failure. Such pit becomes unsafe, not easily accessible, increases loading costs due to production of oversize, longer cycle times among others (Oageng, Joseph and Munyandzwe, 2008). A change in the overall pit slope has a great consequence on the …show more content…
Bore hole inclinometers; and 5. Extensometers anchored within the rock mass. It is recommended that these equipment be installed with warning devices attached to them such as a horn or a flashing light. Monitoring helps to identify the source of error and provide more information on the mode of failure from which the best course of remedial action can be established (Anon, 1999). Wall control blasting techniques also help remedy pit wall failures and are mostly used to keep the final pit wall stable. A number of techniques exist and new ones keep emerging considering how dynamic the mining industry is. All these are done to keep a stable pit wall as well as ensure a safe environment for all. 3.2 Controlled Blasting In open pit mines, high steep slopes are normally required to prevent wall failures, costly scaling and to also reduce the cost of excavating waste rock. Controlled blasting methods are used to minimise or regulate blast induced effects such as; overbreak, fractures in remaining walls, and ground vibrations (Sharma, 2000). Advantages of Controlled Blasting 1. Reduce damage on the rock. 2. Improve the competence of the rock. 3. Control overbreak and backbreak. 4. Evenly distribute the energy delivered by the explosive in the rock
This rock type could prove dangerous, being soft and with little solidness in its structure. Therefore placing the protection over the rock cliffs was a very well thought and planned engineering
This act dramatically changed the safety in mines
Often, the effects of Mountain top Removal are disastrous, the wildlife habitat is damaged and vegetation loss usually leads to numerous floods and landslides. When explosives are used, fly rock, ...
The subsoil is likewise a source of riches. An example of this is the world’s largest open cast coalmine, located on the peninsula of La Guajira, which pro...
This is related to the blending of the fluids and rocks of the reservoir. Skeletal properties of interest to reservoir engineers include porosity, pore size distribution, compressibility, and absolute permeability of the rod. Interaction or dynamic properties of reservoir rocks are affected by the nature and by its interaction with present fluids, as...
Natural stone arches are geological formations that occur when rock is exposed to substantial amounts of erosion , which over time forces the rock into the shape of an arch. Stone arches are among the most diverse of rock formations, not only because of the large area where they are known to be found, but also their complex ways of forming. Although many factors contribute to making natural stone arches so enthralling, one key role keeps and hones our constant attention: each and every stone arch every formed will fall. Despite the things we do know about stone arches, they are continuously changing and teaching us new things about them as well as the world around us.
Open pit mining. It is also known as strip mining. It begins with the removal of soils on the surface and inefficient rock to get at the ore below. This is only possible in some cases, generally when the ore is less than 120 metres below the surface.
These technologies are found in nearly every aspect of mineral development activity - from exploration methods, through production, mineral processing and even marketing. Computers and related equipment now have a lot of different applications in geophysical logging, geochemistry, geological mapping and surface contouring5. At the mine planning stage, the job of designing a mine is now greatly simplified by automation. Through the use of advanced software, geological models can be produced from drill hole data. Computers are also being used to develop plans for mine expansion, develop mining schedules for yearly, quarterly and in some cases, weekly operations. At the operating stage, this new technology is everywhere6.
Nowadays, it will not be inept to inform that the universe is going over a construction boom. In truth, in the past few decades an entire affair of construction has altered dramatically like all other aspects of life. Currently, construction is no more just about keeping one brick above the other, but a diverse more than that. With the present scenario, the construction work encompasses all the aspects of construction like, performance, optimization, developing and designing. As an outcome, construction chemicals have become an essential part of the world construction industry. These chemicals are typically utilized to impart different properties into the layout.
The accidents involving machinery kill and/or hurt more coal miners in a year than any other mining accident. The machinery in mines are located in cramped spaces with little light, causing miners to have two times the chance of accidents. The accidents involving roof and rib failures can usually be averted if a mining company has a roof support plan. For a roof support plan to be made, information like entry widths, mine geometry, the number of pillars that must be left up right, and the number of bolts that must be used are needed (Cobb 3 of 5) Accumulations of gases in underground coal mines is another very serious hazard. If certain gases like methane and carbon monoxide are at or above 5% in the air they can cause violent explosions. Blasting in coal mines are the main cause for such dangerous levels of carbon monoxide.
Acid mine drainage refers to water (leachate, drainage or seepage) that has come into contact with oxidised rocks or overburden that contains sulphide material (coal, zinc, copper, lead). Keller, 2000; U.S.G.S. ; U.S.E.P.A., 2002). A common sulphide is pyrite, or iron disulfide (FeS2). Throughout this essay, it will be pyrite that will be the primary sulphide considered. Acid mine drainage is not a new phenomenon, early mining techniques utilized gravity to avoid water pooling, resulting in the water becoming polluted by acid, iron, sulphur and aluminium (U.S.E.P.A., 2002).
Yet the general application of the wall has been used primarily to either wall something out, or to keep something walled in. The earliest walls were made with a human skill called stone masonry which is the skilled stacking of stones to form a cohesive structure. Walls as just a singular structure and not to be considered as part of an enclosed building with a roof, is a general subject that changes details from area to area. Walls the keep things in have generally been used as a way to border up local activities within a certain amount of space. Some more obvious examples of walls as barriers to keep things within the walls include; prisons, walled-in private communities, farm fences, and other examples where people want to maintain their own private space. Walls that can do the exact opposite of keeping substance inside are meant to be obstructions that keep other things outside from a space. National and private borders are an example of walling out unwanted factors. Security fences, walls as defensive locations, and walls simply placed for the sole purpose of obstruction are effective obstacles that humans have been building for centuries.
... although we may never be able to understand exactly what soil failures can occur when a natural disasters take place, as time goes on and testing instruments and materials advance we will hopefully have a better understanding of what we can do to avoid soil failures and come up with a better and more sufficient method of improving the soils structure and strength permanently. While researching the information for this report I feel I have a much better understanding for construction geo-technics and foundations especially regarding the deformation, liquefaction and pile information related to this specific event. I hope to carry the information I have learned from this event into the construction field and apply them towards an authentic project that’s taking place and know that the information, regarding soils, I have given input on will be precise and accurate.
Johns Hopkins University. (2009, March). In disaster-prone areas, construction needs a new approach. Retrieved from http://phys.org/news157051992.html
As a result of this process, the mine sites "do not develop normal soil structure or support the establishment of a plant cover". Many mine sites have...