Optimizing the Economics of High Performance Concrete

This paper describes how the Toronto International Airport is in a multi-year expansion program. On the groundside, it has re-configured its access roadway system that leads into the airport terminals and involves many new bridges. High Performance Concrete (HPC) was chosen for durability. The design compressive strength was 35MPa, and a need was seen to demonstrate that this HPC has the same durability characteristics common to high strength HPC, such as the Ontario Ministry of Transportation HPC, which has a minimum 28-day compressive strength of 50MPa, a maximum air-void spacing factor of 0.250 mm, a minimum air of 3% and rapid chloride permeability of 1000 coulombs less. Bridge 201 was selected for this field study to find the optimum compressive strength. It is part of a series of bridges that are connecting a major highway to the airport access roadways. It has five spans with cast-in-place concrete superstructure. A testing program was developed for this 35MPa HPC to verify its strength and durability, and also comparing a rapid non-destructive surface absorption test with the rapid chloride permeability test. The findings indicate that for general use, it would be prudent to specify this mix for 40 MPa design strength. The chloride penetration and air-void system test requirements and the strict curing regime are essential to the achievement of durability. Mix design development for HPC mixes is still required to improve the finishability. Durable HPC does not have to be high strength. This optimum strength will lead to a potential cost savings and lower the cost of HPC bridges, resulting with more HPC being used in bridge construction. The correlation between the surface absorption tests on the trial slab and the deck was poor, but this may be attributable to the surface water on the trial slab. For the deck, these tests show a clear difference between the machine finished areas and the hand finished edges, the edges having a significantly higher surface absorption than the machine finished areas. These results suggest that it would be beneficial for durability to finish the edges with a hand held plate vibrator.

• Corporate Authors:

  National Concrete Bridge Council

  Portland Cement Association, 5420 Old Orchard Road
  Skokie, IL  United States  60077-1083
• Authors:
  • Bickley, John A
  • Fung, Rico
• Conference:
  • HPC: Build Fast, Build to Last. The 2006 Concrete Bridge Conference
  • Location: Reno NV, United States
  • Date: 2006-5-7 to 2006-5-10
• Publication Date: 2006

Language

• English

Media Info

• Media Type: CD-ROM
• Features: Figures; Photos; References; Tables;
• Pagination: 20p
• Monograph Title: HPC: Build Fast, Build to Last

Subject/Index Terms

• TRT Terms: Air voids; Bridge construction; Bridges; Compressive strength; Concrete construction; Durability; High performance concrete; Mix design
• Identifier Terms: Toronto Pearson International Airport
• Uncontrolled Terms: Rapid chloride permeability; Surface absorption
• Subject Areas: Bridges and other structures; Design; Highways; Materials; I24: Design of Bridges and Retaining Walls; I32: Concrete;

Filing Info

• Accession Number: 01036299
• Record Type: Publication
• Files: TRIS
• Created Date: Oct 27 2006 8:14AM