Where blasting results in the formation of large boulders that are too big for the loading equipment to handle, secondary breaking will be needed, either by drilling and blasting individual boulders or by using excavator-mounted hydraulic hammers to break them. This allows them to move from area to area within the quarry, as needed. Loading is usually done with wheel loaders or excavators, which combine adequate loading capacity with maneuverability. With few exceptions, modern quarries rely on drilling and blasting to fragment the rock, which is then loaded onto offhighway trucks or belt conveyors for transport to a processing plant of some sort. The quarry becomes deeper with each subsequent bench, with stepped benches reaching up to the original surface. This is then worked in a 'bench' system, removing the rock in layers that can be returned to year after year as the quarry is developed.
Producing the stone needed for the construction of Great Zimbabwe, for example, is believed to have relied on firesetting to split building blocks from natural granite outcrops, making use of the observation that the local rock weathers naturally along planes of weakness that could be exploited in this way.ĭevelopment of most modern rock quarries involves stripping the overlying soil and weathered rock to get to the hard rock underneath. The use of wetted wooden wedges inserted in natural cracks or in shallow holes, with the swelling of the wood causing the rock to split, dates back to ancient times, as does fire-setting. In the absence of modern technology such as drills and explosives, rock-splitting required the use of other approaches, such as wedging or fire setting.
#Quarry shooting blocks out technic free
The Romans used quarry hammers to isolate the blocks they wanted, then used metal wedges to pry them free from the bedrock. A wider range of rock types was produced, including fine marble, which was used for artwork such as sculptures and in public architecture. The Romans also quarried rock on a vast scale for their construction projects, both for buildings and monuments. Ancient Egyptian stoneworkers cut trenches all the way around the blocks of granite that they wished to extract, isolating them from the bedrock, with the rock then being broken free using massive wooden levers. Granite was also a major building material, especially for detail work, and was quarried directly from the bedrock at locations close to some of the country's largest monuments. In the Egyptian dynastic period, for instance, construction of the earlier pyramids depended mainly on limestone that was quarried using copper hand tools, while later pyramids, although built mainly of mud brick, still used quarried stone for facing.
Within recorded history, we have a better understanding of some of the techniques used in quarry operations. There is certainly evidence for stone production in ancient times from numerous sites around the world, although it is unclear at which stage formal quarries began to emerge, rather than people just making use of naturally occurring boulders. Rock has been quarried for the construction of buildings and monuments since before recorded history. Overhaul program for excavator attachmentsĮlectronic Air Regulation Control System (EARS) Refurbishment program for hydraulic breakers
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