老矿区边坡治理(英文).ppt

Click to edit Master title style,*,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,The Monongahela South No.1 Dangerous Highwall Reclamation Project,City of Monongahela,Pennsylvania,Typical Pennsylvania DangerousHighwall Reclamation Project,The Monongahela South No1 Dangerous Highwall Reclamation Project was very unique project and,everything but a,Typical Reclamation Project,Site of the Whiskey Rebellion,Project Location,Pittsburgh,Monongahela South No.1 Project Site,Background,The site is located 15 miles south of Pittsburgh,The site was surface mined from 1945 to 1947,A 1,000 ft.long highwall(averaging 40 ft.high)and bench were left,The Diocese of Pittsburgh acquired the property in 1950,Construction of St.Anthonys Church was completed on the bench at the site in 1952,The parochial school adjacent to the church was completed in 1954,Site Conditions,St.Anthonys Church,St.Anthonys Parochial School,St.Anthonys Parish House,The Problem,Sign at End of Church Street above Highwall,Highwall West End of Site,Highwall Middle of Site,Highwall East End of Site,High Potential for Continued Rock Falls School Closed,Design Summary,Design completed by GAI Consultants,Inc.of Pittsburgh,PA,Awarded a two-phase design contract in June 2002,Phase 1 Alternatives analysis,Completed in October 2002,Cost:$24,860,Phase 2 Final design of preferred alternative,Completed in March 2003,Cost:$68,423,Selected Alternative,Excavation of the unstable highwall to reduce the slope of the eastern end of site,Construction of a soldier pile and lagging retaining wall to stabilize the western end of the highwall,Due to the proximity of homes and Church Street above the highwall and the school and Parish house below,cutting the highwall back in this area was not feasible,Design Challenges,Safety(for both the contractors employees and the general public),Long-term stability of the reclaimed site,Construction and maintenance costs,Accommodating the long-range plans of the Parish,Maintaining normal operation of the church during construction,Design Challenges,Disposal of excess fill material,Incidental coal extraction,Sealing abandoned mine openings located at the base of the highwall,Management of both storm runoff and mine drainage,Consideration of potential mine subsidence issues/problems,Design Challenges,Constructability of the recommended reclamation methodWorking in an urban environment,Impacts on nearby residential properties,Permitting and other required approvals,Contracting Summary,Advertised for bids in April 2003,Original bid opening in May 2003,All bids rejected,Consultant Engineers Estimate:$923,000,Low bid:$1,450,000,Project re-bid July 2003,Low bid accepted,Alex E.Paris Contracting,Atlasburg,PA,Bid price:$1,249,826,Project Construction,Site Access,Access from State Route 481 Park Avenue,Access Between Highwall and Buildings,12 feet,Staging Area/Parking Lot,Erosion and Sedimentation Controls,Slope Reduction Eastern End of Project SiteInitiation of Excavation for Highwall Slope Reduction East End of Project Site,Bench on Cut Slope,Excess Spoil Disposal,City of Monongahela Disposal Site,Incidental Coal Extraction,Pittsburgh Coal Seam,(Avg.Seam Thickness 6-8 feet),Coal Seam Covering,Wire Mesh Reinforcement,Fiber-Reinforced Grout Application,Finished Coal Seam Covering Looking West,AMD/Stormwater Collection System,Upgrade of,Storm Sewer,System along,Park Avenue,SR481,New Storm,Sewer System,for St.Anthonys,Parking Area,and Church,Street Runoff,Conveyance Channel on Cut Slope Bench,Installation of Mine Drainage Conveyance Pipeline,Installation of Mine Drainage Conveyance Pipeline,Sealing of Mine Entries,Mine Opening at Base of Finished Cut Slope,Mine Entries Cleaned Out,Perforated Mine Drain Pipe Installed in Each Entry,Mine Entry Back Stowed with Stone,Block Wall Seal Construction,Finished Mine Seal Construction,Mine Grouting for Subsidence Control,Grout Injection Boreholes,Grout Injection Borehole,Rock Face Support System,Drilling Anchor Holes,Materials,Bolt Plates,All Thread Rods,Center Stabilizers,Rock Netting Bolts,Materials,Epoxy Resin,Resin Cartridges,Rock Netting and Steel Cable,Cable Eye Bolts,Installing Rock Netting Bolts,Finished Rock Netting Covering Looking East,Soldier Pile and Lagging Retaining Wall,Clearing of Slope Above Highwall,Removal of Abandoned Utility Lines,Drill Rig,for Drilling,of Soldier,and Anchor,Pile Holes,Temporary Borehole Casing,Anchor Pile Beams,Anchor Pile Rebar,Concrete poured around Anchor Pile,Installation,of Soldier,Pile Beams,Concrete Pour around Soldier Piles,Wing Wall at West End of Retaining Wall,Waler Support Brackets,Installation of Waler Supports,Concrete Lagging Panels,Installation of Concrete Lagging Panels,Unloading of Walers,Waler Installation,Walers Installed,Wall Tieback Anchor Rods,Torque Wrench for Installion of Tie Back Rods,Torque Gauge,Installed Tie Back Anchor Rods,Stacker for Placement of Wall Backfill,Completed Stone Backfill Behind Wall,Slope Failure and Collapse of Mine Opening,Construction Problems:,Soil Slip Above Retaining Wall,Soil Slip Above Retaining Wall,Damage to Cut Slope Bench as a,Result of Mine Opening Collapse,Micropile Installation,Removal of Slide Material,Drilling for Micropile Installation,Grout Mixing Kettles,Grouting of Micropiles(Soil Nails),Grouting Operation Completed,Soil Amendments Applied to Re-graded SlopeMulch Blanket Installed to Slope,Rock Netting Anchored to Micropiles,Completed Slope Stabilization Work,Completed Slope Stabilization Work,Stabilization of Fractured Highwall,Placement of R-8 Rip-Rap to,Stabilize Collapsed Mine Opening,Grouted R-8 Rip-Rap Repair Area,Grouted R-8 Rip-Rap Repair AreaRestoration of Cut Slope Bench,Drop Zone and Jersey Barriers,Finished Drop Zone Barrier,Finished Drop Zone Barrier,Security Fencing,Security Fencing East End of Site,Security Fencing Top of Finished Cut Slope,Security Fencing and Barrier,at End of Church Street,Post Construction,Finished Cut Slope and Bench East End of Project Site,Finished Cut Slope and Rock Face,Support System-West End of Project Site,Finished Cut Slope,Rock Face Support System,Coal Seam Covering and Retaining Wall,View of Finished Project from above the Retaining Wall,Finished Project Site Looking East from West End,Project Summary,Project construction began December 5,2003,A final inspection for the project was completed July 14,2005,Final project Cost:$1,474,083.70,Contractor:Alex E.Paris Contracting of Atlasburg,PA,Eliminated 1,000 linear feet of dangerous highwall,Project Summary,27,699 cubic yards of excavation,1,957 tons of incidental coal extraction,792 square yards of rock face support,102 feet long by 28 feet high(max)soldier pile and lagging retaining wall constructed,1,140 linear feet of AMD/storm drain pipe installed,Permanently sealed 4 mine openings,Finished Project Site,(Looking West from East End),After,Before,Before,After,Any Questions?,