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1.0 Ground Nail Wall and Spiling Materials <br />1.1 Ground Nails - Grade 75 thread bar or equivalent in accordance with ASTM A6t5 or Williams 32x mm injection bar <br />fy= 75,000 psi <br />1.2 Spiling - Williams 51mm injection bor. <br />1.3 Grout - Grout may be neat- cement or with sand, with Type II cement in accordance with ASTM C150. Water - <br />cement ratio should be between 0.4 and 0.6. <br />f'c =1,500 psi minimum 3 day <br />f c =3,00 psi minimum 28 day <br />1.4 End hardware - Nuts and washers shall be in accordance with ground nail manufacturers recommendations. Bearing <br />plate shall be in accordance with ASTM A36, Grade 36. <br />1.5 Shotcrete - Shotcrete mix shall consist of Type II cement in accordance with ASTM C150, potable water and normal <br />weight aggregate in accordance with ASTM C33. Admixtures, if used, should be noncorrosive to steel. <br />f'c =4,000 psi (28 -day strength). <br />1.6 Welded wire mesh shall be in accordance with ASTM A185. <br />1.7 Walers and vertical bearing bars shall be in accordance with ASTM A615. <br />fy= 60,000 psi <br />1.8 Strip drains consist of 12" wide dimpled cores wrapped in geotex tile. The compressive strength of the core should be <br />at least 20 psi when tested in accordance with ASTM 01621 and its in -plane flow capacity should be at least 10 gpm /ft <br />when tested in accordance with ASTM D47I6. <br />1.9 Centralizers should be plastic that will provide tree passage of grout and attached to the nails in accordance with <br />t he manufacturer rec C entralizers not required for in jection bars <br />2.0 Ground Nail Wall Sequence <br />2.1 Excavate one lift to a maximum depth of five feet. <br />2.2 Install ground nails at the locations and to the lengths shown on the plans. Ground nail location may very by <br />up to 6 ". Tremie the grout from the bottom of the hole up. <br />2.3 Install strip drains welded wire mesh, walers and bearing bars as shown on the drawings. Use chairs to hold <br />the welded wire mesh away from the sail as necessary. <br />2.4 Install shotcrete to the minimum thickness shown an the drawings and to attain the minimum coverage's specified <br />herein. Give special attention to filling the void in the bore hole above the grout line. Cold weather protection <br />measures may be necessary. <br />2.5 Install the ground nail end hardware of ter the minimum inside coverage specified herein has been attained. While <br />the shotcrete is still wet, embed the plate into the shotcrete surface until there is no void behind the plate. <br />Hand tighten the nut. <br />2.6 Once the grout and shotcrete have attained 80% of their specific strengths, repeat 2.1 -2.5 to the bottom of the <br />wall. <br />2.7 At the bottom lift, complete strip drains to daylight os shown on the drawings. <br />3.0 Ground Nail Wall Design Parameters <br />3.1 The ground nail wall has been designed in general accordance with procedures contained in the FWHA "Manual for <br />Design and Construction Monitoring of Soil Nail Walls ", Report No. FHW A- SA- 96 -069R. <br />3.2 The following strength parameters walls were assumed: <br />f c g Sub <br />(deg) (psf) (pcf) (psi) <br />Existing Subsoils 30 100 125 20 <br />An experienced geotechnical engineer should verify the above design parameters during construction. <br />3.3 Groundwater level was ossumed below the base of the wall. <br />3.4 Factors of safety <br />Global - FS > 1.35 <br />Nail Tension Strength Factor - ON = 0.55 <br />Nail Pullout Resistance Factor - 00 = 0.50 <br />Nail Head Strength Factor - OF - 0.67 <br />3.5 Surcharge loading <br />No surcharge loading was assumed for design. <br />3.6 Corrosivity is assumed to be low. <br />3.7 The maximum design life of the soil nail shoring is 10 years. <br />3.8 The spiling is considered a temporary support feature to facilite <br />steel arch placement. <br />)A <br />Yeh and Associates, Inc NaR <br />Consulting Engineers & Scientists <br />4.0 Special Notes <br />v <br />4.1 Wall geometry used in design was basetlrop surveyafrom <br />4.2 This design is valid only for B &JDri{G p hg at the subject site. <br />\�� -d /��l <br />4.3 Yeh and Associates is not responsi ble for.�m� ointaining sbpe /Statiflity above <br />construction. <br />4.4 The contractors are responsible for field=- eating�llo utilities. Conflicting utilities may require ground nail wall <br />redesign at Yeh and Associates' discretion. \ <\� <br />4.5 Yeh and Associates is not fo /quaity control, quality assurance, changed conditions or problems resulting <br />n - <br />from improper constructiotechniques,. and' construction site safety. <br />4.6 Yeh and Associates is not pon ib ttfo or layout. <br />4.7 IT IS ASSUMED THEq.sPILING SOPPOR TEMPORARY TO FACILITE CONSTRUCTION OF THE PERMANENT <br />PORTAL /ADIT /ARCHSSET. IS uIS/ALSO ASSUMED NO MORE THAN 6 FEET OF THE SPILING SHALL BE <br />UNSUPPORTEDv,DURING CONSTRUCTION OF THE STEEL ARCH SET AT ANY ONE TIME. <br />�� <br />4.8 YEH ANDll ASSOCIATESANC RESERVES THE RIGHT TO MODIFY OR CHANGE THE DESIGN BASED ON THE <br />GROUNDD DURING CONSTRUCTION <br />DRAWN BY: WAY <br />CHECKED BY: SPA <br />DESIGNED G01, RIO GRANDE SILVER <br />PROJECT NUMBER'211 -190 <br />SCALE <br />VERT: <br />Russell Surveyors plans dated 10.6.2011. <br />DATE: 10 -11-11 PROJECT: <br />DATE: IO.,a.11 <br />and below the ground nail wall during <br />BULLDOG MINE <br />GENERAL NOTES <br />SHEET <br />2 <br />Of <br />9 <br />