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. ~ .~ ..~-ril,~... <br />MINE OPERATIONS S61 <br />Table 6. Types of Damage Rsletad to tln Peak Putlele Veledty in the <br />Ground Wares from Bhate <br />Peak PsNW Vdotiry <br />Thrashoa a wwat <br />Oamap Sorb ' <br />Type of StrucNn Typa of Dsmaga mm s la par sae <br />Rigidly Mounted Trlp Out 1225 0.5 <br />Mercury Swiunat <br />Houses Pbsbr Cn[eking 50 2 <br /> Sat Inltlsl LImN <br /> o} 125 mm/s <br /> (5 In. par sect Msslmum <br /> at fM Crwher <br />Concrete 81ock Cracks N Blocks 200 8 <br />u In a Haw House <br />Cased Drill Nobs <br />Rabining Walla, Fbrirontal Oflsat 375 18 <br />Lowe Greund . <br />Machanlnl <br />Equlpnrora <br />Pumps <br />Compressors SMns Mlullgnad 1000 a0 <br /> Beyond 250 mm/s <br /> (10 In. par see) hblor <br /> Damap Sorb. Such <br /> u Petsibb CncklnB. <br /> of Genera[ Block <br />PrslebAntad MMeI <br />Bullding on <br />Concrete Peda Cracaed Pads <br /> Building Twbted and <br /> Distorted 1500 60 <br />Table 6 pmrnts the type ddamage that can bs eapeeted <br />in rcladon to the threshold values d peak particle veladey <br />taperitmtxd to the grotutd waver from blatn Act ran be tam. <br />the onset of yusta waeldng is Louses ocean at ^ •a~*cra <br />peak particle velac7ty value d 70 arm/s (2 ter./sea} Thu <br />is an aht[ost vaivasally atxep[ed damage ootttrol airctia is <br />North America. In Fg. 40, the pale pardde veladry damage <br />tlueshdd wltta hove bees supetimptued on the oppar Wait <br />Wes. Ice atldidoa vtbratioa uveu !br tiur3u sad bush and <br />damage to wars well are shown. Thi; thta, assn a uaeAtl <br />guide with regard [o safe sealed diatant:u flat rosy >» em- <br />ployed. <br />Human Raeponsa to Bloat Ydtntlon <br />Fg. 41 shows the resahs d [he etperimettbl work d <br />Ooldmaa (1948) 1a whlah tan were madtrcted using sia- <br />usoidal meehaninl nbtatlow d diSataot tnqumdn sad <br />particle velocity on h»maa test sttbjeets. Sims sTb fialoeaey <br />of pit busts am oSea is the ranged ]0 t0 30 cycles pa <br />+eeoad, thm [Lis data un be used m detesteins the rmge <br />of soled distance from the ph blase peak particle veladty <br />apps ]Imitations ere whloh cabin htemaa tsstetiws rake <br />Puce Thu has ben does W flg. 42 from wbirh h tan be <br />scan the[ blast vibraatioo e8eeb became httole:able to homuu <br />at ]eveu appreciably lows than Ieveu ere which stsuctunl <br />damage takes place. The molt is shat oflea eemplainb can <br />be received due to human ttsponsa and as due so a situation <br />Prodoring damage and is these instances a raductlon W the <br />peak pardele vekxity limit m takc era d this dmatioa b a <br />toad philosophy, PattleuLrly fT tttch a change tlaea rat pea <br />duce opetationd diSealties. I.lo[ib rued is the US d peep <br />particle vebdty d 133 mm/a (0.S in. per s«) redun the <br />ttt®ba of tnmpLmb by a factor d three wmpared to 10 <br />t®!s (2 ice. per sae). It hn ben noted by the USBM that <br />the petoentage d pwpk oomplaftting shoot blast vibration <br />m one cawtrucdoa site was as hlgL as 309b et 30 tram/s <br />(2 ice. pa sec), 1096 et 125 tom/a (0.3 ice. pa see), sad <br />196 at 2 torah (O.Og W. per sea). which is just in the <br />pccepdble tangs to soma uatances, therdom, the hvmm <br />response bemmes the moor eLmen[ u the bun desigtt. <br />The tmseae busting code for Oaarla Ganda falls for <br />a ma>imum peak Astride velodsy d 10 stun/s (0.4 ice. pa <br />see). <br />Moue sad Alr Bleat <br />VVklmeaer a prefsum wave taveLt through the air Sestet <br />rhea a sound wave, it psodttm a sbttek wave The airborne <br />pamure wave emanated from en eiplasieo, called air bun, <br />it a shale trove. wt 11th ie traveU d sapenastie speed. hot, <br />depmding as the tnagait[tde d the energy tr]nsed by the <br />nploeior4 !t will decay is time to as ordinary soaad wave <br />Noise aft sand is • presause wave tnrelutB thtottth air <br />at appsasimately 333 m/s (1100 fps} A sand wave ~""""' <br />d a aaia d di6h pemsnre regions following one another is <br />rapid suomdon with the fregamtiy of the sound and sep• <br />anted by regions dlowa paasme. The.feegnatey daaatd <br />varies Son approatmately 20 to 20,000 1fa. which u the <br />cage that too normally ba detected by the human ens. <br />Air butt sera to a sitaBtr mamas to raise or sound as <br />it is also a ptetsutrtype wave, FIowava, it has s grout <br />spaced than that d sottad sad in fttagoeacy V ]ass than 20 <br />lie, so eansegtuntly it caoaot bs heard. Iu eS«t, though, <br />