搜索
山东科技大学学士学位论文附录1附录外文翻译APPLICATIONOFBLASTINGINDRIVINGTUNNEL1FRAGMENTATIONFragmentationisthebreakingofcoal,ore,orrockbyblastingsothatthebulkofthematerialissmallenoughtoload,handleandtransport.Fragmentationwouldbeatitsbestwhenthedebrisisnotsmallerthannecessaryforhandlingandnotsolargeastorequirehandbreakingorsecondaryblasting.Energymustbesuppliedtorockbydirectorindirectmeanstofragmentthatrockandthetypeofloadingsystem.Fragmentationenergyisconsumedbythemainmechanisms:(1)creationofnewsurfacearea(fractureenergy),(2)friction(plasticity)and(3)elasticwaveenegydispersion.Theloadingmethoddeterminestherelativeproportionsandtheamountofenergyconsumedinfragmentingagivenrocktype.Unonfinedtensilefailureconsumestheleastenergywithanincreasinga,mountofenergyrequiredastherockismorehighlyconfinedwithinacompressivestressfieldduringfragmentationThewayenergyisappliedbytoolstocauserockormineralfragmentationisimportantindeterminingfragmentationefficiency.Tobestdesignfragmentationtoolsandoptimizefragmentationsystemsitwouldbedesirabletoknowhowrockpropertiesinfluencebreakage.Thestrengthofrockisinfluencedbytheenvironmentalconditionsimposedontherock.Thoseofmostimportanceinrockare(1)confiningpressure,(2)porefluidpressure,(3)temperatureand(4)rateofloadapplication.Increaseinconfiningpressure,aswithincreasingdepthbeneaththearth'ssurfaceorundertheactionofafragmentationtool,causesanincreaseinrockstrength.Apparent山东科技大学学士学位论文附录2rockstrengthdecreasesasporcfluidpressureincreases,sinceitdecreasestheeffectofconfiningpressure.Althoughchemicaleffectsofporefluidsinfluencerockstrength,theygenerallyaresmallcomparedtotheconfiningpressureeffect,exceptforasmallminorityofrocktypes.Increaseinrocktemperaturecausesadecreaseinrockstrength.Thiseffectisverysmallbecauseofthesmallambienttemperaturechangesfoundduringmining.Anincreaseinrateofloadapplicationcausesanapparentincreaseinrockstrength.Rockexhibitsdirectionalpropertiesthatinfluencethewayitbreaks.Theseareembodiedintheconceptofrockfabric,whichconnotesthestructureorconfigurationoftheaggregatecomponentsaswellasthephysicalormechanicalpropertymanifestations.Rockfabricontonlyrelatestothepreferredorientationofmineralconstituentsandtheirplanesofweakness,butalsototheconfigurationofdiscontinuities,microcracksandpores.Jointsandbeddingplaneshavegreatinfluenceonfragmentationatfieldscale.Physicalpropertiesofrock(density,indentation,hardness,abrasivehardnessandporosity,)arefrequentlyusedinconjunctionwithmechanicalpropertiestodevelopbetterempiricalestimationsofrockfragmentation.2BLASTHOLECHARGINGMETHODSDrillholechargingcanbecarriedoutindifferentwaysdependingonwhethertheexplosiveusedisincartridgesorintheformofloosematerial.Theoldestchargingmethodimpliestheuseofatampingrodandthissystemisstillusedtoaverygreatextent.Duringthelast20years,compressedairchargershavebeenusedandthesemachinesprovidebothgoodcapacityandalsoanimprovedlevelofchargeconcentrationsothatthedrillholesareutilizedtoa山东科技大学学士学位论文附录3higherdegree.Duringthelastfewyearssemi-automaticchargershavebeentakenintouse,primarilyinundergroundwork.Compressedairchargersforblastingpowderintheformofloosematerialhavealsocomeintouseonalargescale.Asfarasslurryblastingisconcerned,specialpumpingmethodshavebeendevelopedthroughwhichchargingcapacityinthecaseoflargediameterdrillholesispracticallygood.Atampingrodmustbemadeofwoodorplastic.Itmustnotbetoothickinrelationtothedrillholediametersincethiscancrushanddamagefuseorelectricdetonatorcablesduringchargingwork.Ifagooddegreeofpackingistobeobtainedduringchargingwithatampingrodthenonlyonecartridgeatatimeshouldbechargedandtamped.Thedetonatormustbecorrectlyfedintothedrillholeduringchargingwork.CompressedairchargershavebeeninuseisSwedenforabout20years.Thefirsttypeconsistedofaluminumpipesconnectedtogetherandthecartridgeswereblownintotheholewithanairpressureof42poundspersquareinch.sincethattimethechargingtubehasbeenreplacedbyanti-statictreatedplastichoseofaspecialdesign.Achargerincludesafoot-operatedvalve,reductionvavlewithairhose,breech,connectingtubeandcharginghose.Thesemi-automaticchargerpermitsthecontinuousinsertionofexplosivecartridgeatthesamerateastheyarechargedintheholebythehose.Insteadofavalvebeingused,thecartridgespassthroughanairlockbetweentwoflaps.Theairpressureinthecharginghoseisretainedwhilecartridgesarepressureinthecharginghoseisretainedwhilecartridgesarebeinsinserted.Thesemi-automaticchargerpermitsconsiderablyhigherchargingcapacitythanthe山东科技大学学士学位论文附录4normaltypeofcharger.Explosivesintheformoftheformofloosematerial,usuallyammoniumnitrateexplosives(ANFO),requirespecialchargers.Twotypescanbedifferentiated:pressrurevesselmachinesandejectorunits.PressurevesselmachinesareparticularlysuitableforcrystallineAnexplosiveswithgoodchargingcapacity.Ejectorunitsareoperatebyanejectorsuckingupexplosivefromacontainerthroughacharginghose.Theexplosiveisthenblownthroughthecharginghoseintothedrillhole.Thereare,alsocombinedpressureejectormachines.ThecharginghoseusedforANFOchargingoperationsmustconductelectricityandhavearesistanceofatleast1KΏ/mandmax.30KΏ/M.Ni