PERFORMANCE OF COMPOSITE LIGHTWEIGHT CONCRETE DECKS ON STEEL STRINGERS

RESULTS ARE PRESENTED OF A FIELD AND ANALYTICAL STUDY INTO THE CAUSES OF CRACKING OF LIGHTWEIGHT CONCRETE BRIDGE SLABS IN LOUISIANA. THE FIELD STUDY INVOLVED THE DETERMINATION OF THE PRESENT CONDITION OF 389 SIMPLY SUPPORTED LIGHTWEIGHT CONCRETE BRIDGE SLABS BUILT COMPOSITELY WITH STEEL STRINGERS. THIS INCLUDED A CRACK SIZE AND DISTRIBUTION STUDY AND A DETERMINATION OF REINFORCEMENT EMBEDMENT DEPTH. AVAILABLE CONSTRUCTION RECORDS WERE REVIEWED, CLIMATIC CONDITIONS TO WHICH THE STRUCTURES HAD BEEN SUBJECTED WERE STUDIES ALONG WITH THE TRAFFIC HISTORY OF EACH BRIDGE. THE ANALYTICAL STUDIES ATTEMPTED TO RELATE DESIGN CRITERIA, DYNAMIC BEHAVIOR OF THE STRUCTURE AND CONCRETE SHRINKAGE TO THE PRESENT CONDITION OF THE BRIDGE. SOME OF THE CONCLUSIONS PRESENTED WERE: (1) THERE APPEARS TO BE NO REASONABLE RELATIONSHIP BETWEEN SLAB DETERIORATION AND MOST OF THE VARIABLES INVOLVED IN DESIGN AND CONSTRUCTION. (2) IF THE CONCRETE COVER WAS LESS THAN 3/4 INCHES, THE CRACKS TENDED TO COINCIDE WITH REINFORCEMENT ORIENTATION. IF THE COVER WAS LARGER, NO RELATIONSHIP BETWEEN CRACKS AND REINFORCEMENT ORIENTATION EXISTED, (3) SHRINKAGE STRAINS AS ANALYTICALLY DETERMINED ARE AS GREAT AS THE APPROXIMATE TENSILE STRENGTH OF THE CONCRETE, (4) THE DYNAMIC BEHAVIOR ANALYSIS POINTED TO THE SUPPOSITION THAT FOR SOME SPAN LENGTH AND LOADING COMBINATIONS, CRACK PROPAGATION IS CAUSED MAINLY BY OSCILLATIONS DUE TO MOVING VEHICLES. /BPR/

• Supplemental Notes:
  • Hpr-1/3/, STATE NO 63-6C
• Corporate Authors:

  Louisiana State University and Agriculture & Mechanical College, Baton Rouge

  Baton Rouge, LA  United States  70803

  Louisiana Department of Highways

  P.O. Box 44245, Capitol Station
  Baton Rouge, LA  United States  70804
• Authors:
  • Turner, H T
  • Aguilar, R J
• Publication Date: 1965

Subject/Index Terms

• TRT Terms: Anchoring; Bridge decks; Climate; Composite construction; Concrete; Cracking; Depth; Fracture mechanics; Lightweight concrete; Material reinforcement; Motion; Motor vehicles; Oscillation; Shrinkage; Slabs; Steel; Stringers; Structural analysis; Tensile strength
• Uncontrolled Terms: Crack propagation; Moving vehicles
• Old TRIS Terms: Embedments (Concrete)
• Subject Areas: Bridges and other structures; Highways; Pavements;

Filing Info

• Accession Number: 00207843
• Record Type: Publication
• Source Agency: Bureau of Public Roads /US
• Files: TRIS, STATEDOT
• Created Date: Dec 21 1994 12:00AM