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• <br /> nyrni L..!.. .J <br /> N <br /> ,.. <br /> +362.30 E C 10,e.ti 445.000 e <br /> \/,,, {562.600 N . <br /> ~' -- <br /> 0 MX <br /> 4 <br /> Scato.ft tali <br /> 0 100 200 I 20 17— <br /> �2 <br /> IScala.m 261, <br /> KEY 1 J <br /> • Meng beet°!°for•et sl01 <br /> -- fence mound Oman*fiord <br /> 11 hetrynlenl acted <br /> 0 Outline of dvmpurden pleat e <br /> {D alai.of Darling mast <br /> Figure 1. Minnehaha mine pipeline test area and production blasts monitored <br /> Strains <br /> Figures 6 through 10 show a variety of compar- 1,- 0 e.' 0' ' <br /> isons of measured strains and surface ground vibra- • I- ° 2"c" - <br /> dons. These are obviously not the only correlations i 1- 0 . <br /> possible out of 34 total independent channels and, In - - <br /> 0 <br /> some opinions, not the best choices. The SwRI - <br /> authors calculated stresses from blasting parameters 1 ,. 0 a <br /> • <br /> (explosive type, amount, distances, etc)and believe 2- <br /> that particle.velocities will not consistently be relat- ,- i - <br /> ed to strains (ind stresse$. The Fig. 6-10 plots sug- °==--� <br /> e 2 4 I e 10 17 14 to II to <br /> gests that rough correlations with velocities or at <br /> ar:m,.o H012xn0n,KAOK.4n. <br /> Figure 5. Ground and pipeline vibrations <br /> GROUND VIBRATION DATA,41PLITUDE 2.0 Ws:1 <br /> r v i 4 <br /> \- ---- lest maximum envelopes covering all the highest <br /> Surface.! measurements are possible. Alternatives could be <br /> • direct pipeline vibration response, conversions of <br /> Surface,motet velocities to displacements, computations of stress <br /> and strain propagation equations, etc. The authors <br /> anticipate future examinations of alternatives, <br /> PIP`ELINE STRAIN DATA,AMPLITUDE 50µe:I Strains are relatively high for the PVC pipeline by <br /> +- i contrast with the steel, consistent with its lower <br /> V 1� a Mal PVC,Top w,wrndw,r stiffness. If the pipelines were all fully coupled and <br /> V <br /> t moving with the ground, this difference should not <br /> 8-Inch,Front lontitodlnal exist. This problem will be examined in more detail <br /> in the follow-up comprehensive report. Generally, <br /> a•Mdt,Top dreumferentW similar measurements on the steel pipelines gave <br /> aLldt Top fe/gtegtnel similar amplitudes (e.g, front longitudinal measure- <br /> ments. Circumferential strains were often, although <br /> le-Ndt Top longitudinal not always, the highest, particularly when measured <br /> 20rld,.Tepwarpl.mntI.f on top compared to on the side. <br /> Compared to previous studies, strains were vela- <br /> :Otnd,Topb�plNdkW tively low for given particle velocities. The large <br /> blasts involved in this study; produced high particle <br /> r velocities at relatively large distance. Hence, the <br /> 0.0 °.s to 2.0 pipelines experienced high vibration amplitudes at <br /> TIME,Sec <br /> Figure 4. Vibrations and strain time histories distances beyond the inelastic zone. In addition, <br /> for blast No. 25 charges are in blastholes,__being vertic:o! columns <br /> -. t which are long compared to the closest blast to <br /> 35 <br />