OVERLAY AND WIDENING WITH HOT MIX ASPHALT CONCRETE

THE USE OF FULL DEPTH ASPHALT CONCRETE FOR WIDENING, AS USED BY MISSISSIPPI AND LOUISIANA, IS REVIEWED. A MAJOR PROBLEM IN THE DESIGN AND CONSTRUCTION OF AN OVERLAY AND WIDENING PROJECT IS THE PREPARATION OF THE OLD PAVEMENT FOR APPLICATION OF THE NEW SURFACE. A SUCCESSFUL METHOD OF PORTLAND CEMENT CONCRETE PREPARATION USED BY IOWA, FLORIDA AND LOUISIANA IS THE BREAKING OF THE MOVING SLABS BY A DROP HAMMER AND SEEDING THE BROKEN SLABS BY ROLLING WITH A 50-TON PNEUMATIC TIRE ROLLER. THIS IS USED EXCEPT FOR PORTLAND CEMENT WHICH IS WIRE MESHED REINFORCED. TO REDUCE THE EFFECT OF THE WIRE MESH, THE MESH WAS CUT WHERE THE SLAB WAS SCORED. FIFTY PERCENT OF THE SLABS WERE SEEDED SUCESSFULLY AND FIFTY PERCENT WERE REMOVED AND REPLACED WITH FULL DEPTH ASPHALT CONCRETE. FOR THE WIDENING OF AN EXISTING NARROW PAVEMENT LOUISIANA AND MISSISSIPPI SELECTED FULL DEPTH ASPHALT CONCRETE. THE WIDENING THICKNESS FOR AN EXISTING PAVEMENT OF PORTLAND CEMENT CONCRETE IS GENERALLY A COMPACTED THICKNESS EQUAL TO THE SLAB THICKNESS PLUS ONE-HALF INCH. WHERE THE EXISTING PAVEMENT IS ASPHALT, THE THICKNESS OF WIDENING IS FOUR INCHES. WHERE IT MAY BE FOUND NECESSARY TO PLACE THE WIDENING ON ONLY ONE SIDE OF THE PAVEMENT THE WIDTH IS USUALLY 6 TO 10 FEET. FOR SAFETY AND CONVENIENCE, THESE STATES REQUIRE THAT THE ENTIRE LENGTH OF EXCAVATED TRENCH MUST BE COMPLETED WITH COMPACTED ASPHALT CONCRETE AND OPEN TO TRAFFIC BY THE END OF THE WORK DAY. ONE CONTRACTOR WITH AN EFFICIENT OPERATION PLACED AN AVERAGE OF 2600 TONS OF FULL DEPTH WIDENING PER DAY.

• Supplemental Notes:
  • Bull No 35, PP 29-32
• Authors:
  • McKeogh, C A
• Conference:
  • Tennessee Highway Conference Proc
• Publication Date: 1969-1-1

Subject/Index Terms

• TRT Terms: Asphalt concrete; Bituminous overlays; Cutting; Fracture mechanics; Hot mix asphalt; Material reinforcement; Pavement maintenance; Pavement widening; Pile hammers; Pneumatic equipment; Portland cement concrete; Rollers; Slabs; Thickness; Wire mesh
• Old TRIS Terms: Pneumatic rollers
• Subject Areas: Highways; Maintenance and Preservation;

Filing Info

• Accession Number: 00218663
• Record Type: Publication
• Files: TRIS
• Created Date: Oct 13 1970 12:00AM