PARTIAL PRESTRESSING IN CONCRETE BRIDGES

This report gives information on: (1) the purposes, advantages and disadvantages of partial prestressing and the relation between serviceability and strength requirements; (2) the flexural analysis of partially prestressed concrete members, namely elastic theory for flexural stresses in cracked sections in the service load range and flexural strength theory for the ultimate load; (3) serviceability limit state considerations: stress, fatigue, flexural cracking and deflections. Experimental results from tests conducted on some partially prestressed concrete beams are also included; (4) a review of serviceability limit states for partially prestressed concrete from selected national codes of practice and considerations of serviceability and strength design criteria for highway bridge beams. Also presented is a study of a range of MWD (Ministry of Works and Development) standard bridge beams to determine the possible increase in design loading if a partially prestressed concrete design approach is adopted. Special consideration is given to the design of partially prestressed concrete members in accordance with the New Zealand Concrete Design Code NZS 3101: 1982. It is considered that sufficient design information is now available for a more general acceptance of the use of combinations of prestressing tendons and nonprestressed longitudinal reinforcing steel in concrete members cracked at service loads. (TRRL)

• Corporate Authors:

  National Roads Board

  Road Research Unit, P.O. Box 12-041
  Wellington,   New Zealand 
• Authors:
  • Park, R
  • Dean, J A
• Publication Date: 1984

Media Info

• Features: Figures; References; Tables;
• Pagination: 85 p.
• Serial:
  • RRU BULLETIN
  • Issue Number: 69
  • Publisher: ROAD RESEARCH UNIT NATIONAL ROADS BOARD

Subject/Index Terms

• TRT Terms: Bending stress; Breaking loads; Bridge construction; Bridge foundations; Bridges; Concrete; Concrete bridges; Construction; Cracking; Deflection; Design load; Elasticity (Mechanics); Flexure; Pavements; Prestressing; Serviceability; Strength of materials
• Uncontrolled Terms: Concrete cracking
• Old TRIS Terms: Elastic theory; Pavement deflection; Service loading
• ITRD Terms: 6471: Analysis (math); 3472: Beam; 3455: Bridge; 5211: Cracking; 5586: Deflection; 9011: Design (overall design); 5912: Elasticity; 5520: Failure; 5579: Fatigue (mater); 5567: Load; 8079: New Zealand; 4796: Prestressed concrete; 4777: Prestressing; 177: Specifications; 5544: Strength (mater); 5575: Stress (in material)
• Subject Areas: Bridges and other structures; Construction; Design; Highways; Pavements;

Filing Info

• Accession Number: 00395075
• Record Type: Publication
• Source Agency: Transport Research Laboratory
• Report/Paper Numbers: Monograph
• Files: ITRD, TRIS, ATRI
• Created Date: Oct 31 1985 12:00AM