Bond of Top-Cast Bars in Bridge Decks

ABOUT THE INTERNATIONAL CONCRETE ABSTRACTS PORTAL

  • The International Concrete Abstracts Portal is an ACI led collaboration with leading technical organizations from within the international concrete industry and offers the most comprehensive collection of published concrete abstracts.

International Concrete Abstracts Portal

  


Title: Bond of Top-Cast Bars in Bridge Decks

Author(s): Rex C. Donahey and David Darwin

Publication: Journal Proceedings

Volume: 82

Issue: 1

Appears on pages(s): 57-66

Keywords: air entrainment; bond (concrete to reinforcement); bleeding(concrete);bridge decks; concrete construction; consistency; consolidation; cover;pullout tests; reinforced concrete; reinforcing steels; resurfacing; vibration.

Date: 1/1/1985

Abstract:
The effects of consolidation method and two-course construction on the bond strength of top-cast reinforcement in concrete bridge decks were studied as functions of slump, bleed, and slab depth. Consolidation was varied using vibrator spacing and insertion time. Four top covers were studied: % and 3 in. (19 and 76 mm) monolithic and 3 in. (76 mm) two-course with either % or I in. (19 or 25 mm) first course cover. Bond test specimens were of two types: shallow, with 8 in. (203 mm) of concrete below the reinforcement, and deep, with 24 in. (610 mm) of concrete below the reinforcement. Concrete densities were obtained from drilled cores. concrete-steel bond. Based on the experimental work, high-density internal vibration provides improved bond over low-density internal vibration. A 3 in. .(76 mm) monolithic cover provides higher bond strength than 3 in. (76 mm) two-course cover. Increased concrete slump has a negative effect on bond strength for top-cast reinforcement. Deep slabs made with stiff, well-consolidated concrete can provide the same bond strengths as shall0 w slabs.