MUS-93-12.84Applied Mine Grouting Technologies P. Paul Painter, PGKirk BeachOhio DOTMUS-93-12.84: Mine Grouting The Ohio Department of Transportation (ODOT) inspects nearly 12,000 structures annually During the inspection of MUS-93-12.84 Bridge in 2007, a large subsidence feature was noted under the right rear abutment Bridge carries traffic over Interstate Route 70 in Muskingum County Determined that corrective actions were necessary to protect the structure and roadwayMUS-93-12.84: Mine GroutingProject Location: Pleasant Grove, OhioSITEZanesville East QuadMUS-93-12.84: Mine GroutingProject Aerial LocationRear AbutmentForward AbutmentI-70 Mainline229322MUS-93-12.84: Mine GroutingSubsidence Feature Noted During Bridge Inspection at Rear AbutmentMUS-93-12.84: Mine Grouting No historical mine maps were available for the workings Historical archives, construction diaries, indicated that Interstate 70 was over-excavated through the mine interval, including the bridge piers, but the north and south bridge abutments and approach roadway and ramps could be underlain by mine voids Original construction plans indicated an abandoned mine entrance within project Underground utility vault, east side of rear abutment, encountered a void uuring installation.MUS-93-12.84: Mine GroutingMUS-40-12.86 Soil Profile - 1962MUS-93-12.84: Mine Grouting Area has been noted for active subsidence:1962: two subsidence features noted on original soil profile notes;2000: large subsidence(s) investigated in northwest quadrant infield; 2007: Subsidence feature under rear abutment.MUS-93-12.84: Mine GroutingREGIONAL GEOLOGY & MINING Area located in the non-glaciated Marietta-Pittsburgh Plateau which is characterized by its moderately high to high relief Pennsylvanian aged bedrock rock consists of siltstone, shale, sandstone, coal, and claystone Locally: No. 7 coal typically mined through drift entries Drift entries advanced into the coal seam from the head of tributary valleys Shallow soil cover typically ranging form 5 to 20 feet No Site Specific Mine Map for the projectMUS-93-12.84: Mine GroutingSiteODNR Map BG-1MUS-93-12.84: Mine GroutingREGIONAL GEOLOGY & MINING Typically: All of the local mines were abandoned prior to mechanization, circa 1930s. Most exhibit pre-mechanization mining features, i.e., Long, Narrow Rooms & Pillars (5-6 foot widths), 50% Extraction, Rooms Driven on the Face Cleat, No retreat or second mining.MUS-93-12.84: Mine GroutingProject LocationLocal AML GIS Coverage ODNR Web SiteKnown Mapped WorkingsMUS-93-12.84: Mine GroutingTypical Mine Map From Area(Local 1 mi. east of project) Rooms driven on Face Cleat; N6W Long, Narrow Pillars No Secondary (retreat) mining Coal Elev. 858.0; 30 ft. below MUS-93 site (El. 890.0) Drift entry from valley outcropMUS-93-12.84: Mine GroutingRemediation Selection Monitoring of the structure and roadway:High traffic resulted in in unacceptable risk due to potential catostraphic failure Excavation and replacement:High costs and long closure timeImpractical at the abutments Drill and grout options:Expensive and small risk for subsidenceDrill and Grout Selected due to time constraints!MUS-93-12.84: Mine GroutingProject Concerns1) Limiting Road Closure Due To Heavy Truck Volumes From Industrial Park2) Limiting Access To Emergency Vehicles3) Settlement of Structure During Grouting4) Blowout of the Cut Slope Above IR 70 MUS-93-12.84: Mine Grouting1) Limiting Road Closure Due To Heavy Truck Volumes From Industrial Park: Selection Of Drill and Grout To Limit The Time Required For The Road Closure Do Not Implement Road Closure Until Drilling Of The Roadway Production HolesMUS-93-12.84: Mine Grouting2) Limiting Access To Emergency Vehicles: Only Work In One Traffic Lane At A Time, Even During Closure Period, To Allow Access To Emergency Vehicles MUS-93-12.84: Mine Grouting3) Settlement of Structure During Grouting: Required Structure Monitoring 24/7 For The Duration Of The Construction.MUS-93-12.84: Mine Grouting4) Blowout of the Cut Slope Above IR 70: Contractor Must Have Contingency For Immediate Interstate Closure If Blow Out Occurs With Cleanup Plan; Monitoring Of The Slope Required During Grouting Operations.MUS-93-12.84: Mine GroutingSTRUCTURE MONITORING Leica RCRP 1200+ robotic system was manned 24 hours a day, 7 days a week during the project Reflective glass targets were mounted on each concrete abutment and concrete pier. Vertical Surface Monitoring Points were surveyed once daily during the project. MUS-93-12.84: Mine GroutingLeica RCRP 1200+Reflective glass targets(Photos Courtesy Gannet Flemming, Inc.)MUS-93-12.84: Mine GroutingMonitoring Results of TargetsMUS-93-12.84: Mine GroutingUNDERGROUND MAPPINGDue To Lack Of Mine Map, In-situ Underground Mapping Was Completed to Determine Working Layout and ConditionWorkhorse Technologies, Pittsburgh PA, Were Retained To Perform Mapping Using Sonar “Wet Ferret” and/or LiDAR “Dry Ferret”MUS-93-12.84: Mine Grouting South and North Side “Dry” a