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Impacts of Mechanical Equipment at Uenwn Eimthers Quarry <br />u i0-yr period. 'fhc resulting PPV caused by an curthyuake occurring at a typical frequency of 1 <br />tlz anJ acceleration of 0.1 Kg would he 61.52 in/s jfQ.l H x 32.2 s 12) ~ (2 x 1.14 x I )). "Ihc <br />partirlc Jisplaccnxnt (actual ground movement) wi,uld he 9.8 inches j61.52 ~ 12 x 1.14 s I )~. <br />In a study (Rcvey, 2p115) recently conJuueJ fur judge in the frmkhn ('ounty ('ircuil ('curt in <br />Frankfurt, KY'. govcmnunt funJed rcscarchcrs ti•um Nurthvvcstcrn Umvcrsrty measured dilations <br />of csisting cracks m bwlding materials cuusod by ground vihranun anJ natural changes in <br />temperature anJ hunuJtty. In this study, JirerteJ by dtc author. crock nn+vrmcntx were <br />nu,nttoreJ by instrumentation that continuously measured dilahuns caused by vibrations and <br />:Ina-acting vveathcr changes. Measurements reve:Jcd that cr.tck dilutiun> rauscJ by swelling and <br />cuntracuons u( Krick anJ concrete-block walls responding to temperature anJ humidity changes <br />were hundreds of times gre:tier than the. dilahuns caused by vibrations caused by hlasting at <br />nearhy ruck quarry. A graph showing crack dilations in a brick wall measured over a 4K-daV <br />pcnud arc shuvvn in f figure 5. Note that the thicker red parts of the plotted dilations caused by <br />vibration arc supenmposed over the much large dilaliunr caused by changing temperature and <br />humidity shown in hlue. <br />En.ror Crack <br />Figure 5: ('mck Diladun ('aused in Brick by Environmental ('hanger anJ (irounJ Vihratiun <br />In the Kentucky study, the unenvty of gntund motions wcrr as high as 0? itL s, which is tour <br />times greater than the peak motiom that woulJ occur in the sandstone blutTs adjacent to the <br />propoud Red tihale (luany. This is very• important hecausc one can clearly conclude that the <br />stress impacts of ground motions in rock surfaces will he hundreds of times Iesr than the normal <br />everyday stresses c:wuJ by normal cnvironmrntal el'licts. <br />It I ~' I' 1' r\,.~+ciatcs, Inc. I+agr. G of 7 February :I11Ri <br />