Laserfiche WebLink
TABLE S-1 (Concluded) <br />Assumptions and terminology used: <br />• pv <br />ph <br />Y <br />pl <br />D <br />4 <br />tan g <br />00 <br />w <br />Y <br />L <br />pillar Width (ft) <br />pillar height (f t) <br />density (lb/cu ft) <br />pillar length (ft) <br />depth of overburden (ft) <br />angle of internal friction (°) <br />1 + sinC= passive pressure coefficient <br />1 - sin4 <br />compressive strength (PSI) at pillar ribside <br />mzximum stable vertical pillar stress (PSI) <br />distance into pillar at location of maximum stability (ft) <br />load carrying capacity of pillar in tons <br />Calculations: <br />. tang = 1 + sin ~ <br />1-sino <br />w = [ (.00694) ~ (Y) (D) (:az6) ] + ao <br />Y = ph [1n w ) <br />• tan6 (tan6 - 1) ~ ao + `, ~n6 <br />L = (0.072) (w) [ (p•+' nl) - (~•,' 1') - (P= - Y) + (1.33 Y2) ] <br />Load = pv ph 158.4 d <br />2000 <br /> <br />S-9 <br />