376 603.10.2.1.2 -Equipment: The equipment to be used to inject the epoxy shall meet the recommendations of the epoxy injection material manufacturer and/or the following requirements:
1.Use equipment that has the ability to automatically proportion the material components within the mix ratio tolerances set by the epoxy materials manufacturer.
2.Use equipment that has the ability to automatically mix the epoxy component materials within the pump and injection apparatus.
603.10.2 1.3 -Crack Surface Preparation and Cleaning Requirements: After the
concrete beam has achieved 28 day shipping stren gth, clean the concrete surface along the crack of all deteriorated concrete, efflorescence and other contaminants which would be detrimental to the adhesion of the surface sealing epoxy compound. The substrate must be sound, dry on the surface, and free from oil and grease. Blow out the crack with oil free and dry compressed air.
603.10.2 1.4 -Epoxy Injection: Place the base of the injection ports directly over the
crack and bond to the substrate with an epoxy paste or the recommended product by the epoxy resin manufacturer. The injection ports should be spaced over the length of the crack at a spacing that will allow the epoxy resin to seal the entire crack traveling from one port to another. The ports spacing is dependent upon the viscosity of the resin. Use an epoxy adhesive to seal over the surface ports and exposed cracks. The entire exposed crack is to be covered with the epoxy adhesive leaving only the port holes uncovered. The cure time for the epoxy will be based upon concrete temperatu re. The temperature requirements of the concrete for the injected resin must be satisfied before the process can begin. Begin injecting at the lowest port on the beam and continue until the epoxy resin begins to “ooze” out of the port above it. The “ooz e” out of the port above it is a sign that the crack has been filled to that level. Plug the first port with a cap and move up to the next port, repeating this procedure until the entire crack has been filled with epoxy. Use slow, constant pressure to in ject the epoxy into the crack which will reduce the possibility of leaks or blow -outs and allow time for the repair material to fully penetrate the crack.
603.10.2 1.5 -Post Epoxy Injection: After a minimum of 24 hours, the injection ports
can be removed from the beam. Clean the concrete surface areas of excess epoxy injection work. Clean so as to not damage the concrete by scraping, light sand blasting, grinding, use of solvents, or any other appropriate method approved by the engineer. Clean the excess materials so that no epoxy material or injection ports extend beyond the plane surface of the concrete.
603.11 Dimensional Tolerances :
All tolerances shall be applied with respect to the theoretical positions and dimensions shown in the plans. The tolerances listed in this article represent the total allowable tolerance that will be accepted in the finished product. The limits of tolerance do not necessarily represent fully acceptable construction; they are the limits at which construction becomes unacceptable. In general, workmanship shall be at a level of quality that wil l be well within the tolerance limits. Out of tolerance dimensions shall be handled in accordance with MP 603.10.40 .
603.11.1 Prestressed Concrete I -Beams and Bulb Tee Beams:
Characteristics Value Depth (flanges) ±1/4 inch Depth (Overall) +1/2 inch, to -1/4 inch Width (flanges) +3/8, to -1/4 inch Width (Web) +3/8, to -1/4 inch Length of Beam ±1/8 inch per 10 feet, ±1 inch max. Sweep (variation from straight line parallel to centerline of member) ± 1/8 inch per 10 ft Camber variation from design camber ± 1/8 inch per 10 feet ± 1/2 inch max up to 80 feet length ± 1 inch max. over 80 length Camber variation from design camber ±3/16 inch per 12 inches ± 1 inch Position of plates ± 1 inch Position of bearing plates ± 5/8 inch Diaphragm Inserts (spacing between centers of inserts and from centers of inserts to the ends of the beams.) ± 1/2 in ch Stirrup bars ( Projection above top of beam) ± 3/4 inch Stirrup bars ( Longitudinal spacing) ± 2 inches Concrete Cover ± 1/4 in ch Position of inserts for structural connections ± 1/2 in ch Position of hold -down points for draped strands ± 5 inches Position of Inserts ± 1/2 inch Position of handling devices: Parallel to length ± 6 inches Transverse to length ± 1 inch Prestressing strand position (vertical or horizontal). ± 1/4 inch 378 603.11.2 Precast/Prestressed Concrete Box Beams and Plank Beams: Characteristics Value Depth (Overall) 1/4 inch Depth (top flange) +1/2 inch Depth (bottom flange) +1/2 inch to -1/8 inch Width (Overall) ±1/4 inch Width (Web) ±3/8 inch Length 3/4 inch Sweep (variation from straight line parallel to centerline of member) Up to 40 feet length member 1/4 inch 40 to 60 feet length member ±3/8 inch Greater than 60 feet length member 1/2 in Camber variation from design camber ±1/8 inch per 10 feet, ±1/2 inch Max. Variation from specified end Squareness of skew: Horizontal 5/8 inch Vertical ±1/8 inch per 12 inches ± 1/2 inch Max. Position of tendons Individual 1/4 in ch Position of Inserts for structural connections 1/2 in ch Position of handling devices: Parallel to length 6 inches Transverse to length 1 inch Position of stirrups: Longitudinal spacing 1 inch Projection above top + 1/4 inch, - 3/4 inch Position of dowels tubes 5/8 inch Position of hold -down points for draped strands 5 inch Position of tie rods tubes: Parallel to length 1/2 inch Vertical ±3/8 inch Position of slab void: End of void to center of tie hole 1/2 inch Adjacent to end block 1 inch Concrete Cover 1/4 inch per 10 feet long. Bars 379 603.11.3 -Prestressed Concrete Deck Panels: Characteristics Value Length 1/2 in ch Width 1/2 in ch Nominal Depth + 1/4 inch - 1/8 in ch Horizontal Alignment – Deviation from straightness of matting edge of panels 1/8 in ch Deviation of ends from plan dimension Horizontal Alignment 1/2 in ch Position of strands : Vertical ±1/8 inch Horizontal 1/2 in ch Concrete Cover 1/4 inch per 10 feet long . Bars
603.12 Handling, Storing, Transporting, and Erection :
The Contractor shall be responsible for proper handling, lifting, storing, hauling, and erection of all members so that they are placed in the structure without damage. Prestressed members shall be maintained in an upright position at all times and shall be handled and supported in a manner which prevents torsion. No member shall be moved from the casting yard until the member has been accepted. Storing of members shall be done with adequate blocking so that warpage or cracking will not occur. Blocking will be such that at least six (6) inches clearance is maintained above the surface on which the blocking is placed. Placement of the blocking from beam en ds shall be at locations not greater than three percent (3%) of the beam length. Concrete box beams shall be supported by the solid end block area during handling, storage, hauling, and erection. Members which are improperly stored and which become cracked , warped, or otherwise damaged in storage will be subject to rejection. Members when stacked, shall be separated by blocking capable of supporting the members. The blocking shall be arranged in vertical planes. Stacking of members shall be arranged such t hat lifting devices will be accessible and undamaged. Stacking shall not exceed two members high. All concrete beams or girders when erected, shall be securely tied and/or braced unless otherwise shown on the plans. When railroad or roadway traffic must b e maintained beneath girders or beams already placed, traffic shall be protected against falling objects during the erection of diaphragms and other structural members, during the placing of cast -in-place concrete, and during the erection and dismantling o f forms. Protection shall consist of nets or flooring with openings not larger than one ( 1) inch. When precast / prestressed concrete adjacent box beams are erected, the fit of mating surfaces will be such that excessive grout leakage will not occur. If s uch fit is not provided the joint shall be filled with grout or sealed with an acceptable caulking suitable to the Engineer.
603.13 Construction of Deck :
The variation in heights between beams shall not be more than ½ inch between adjacent box beams where there is no wearing surface. For adjacent box beam bridges with wearing surfaces, the differential shall not exceed ¾ inches. Dowel bar and lifting bolt holes shall be filled with non -shrink grout. Adjacent box beam units shall be transverse post tensioned by the use of high strength threaded bars, or by other methods as shown on the Plans.
Source: West Virginia Standard Specifications for Road and Bridge Construction, 2023 Edition. Pages 396–399 of 1,006.