Heat Dissipation and Crack Control in Massive Concrete at the Burlington Bridge, MLR-94-1, 1995

(1995) Heat Dissipation and Crack Control in Massive Concrete at the Burlington Bridge, MLR-94-1, 1995. Transportation, Department of

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Abstract

The large concrete placements at the Burlington Bridge were expected to cause great temperature differentials within the individual placements. In an attempt to reduce cracking due to the large temperature differentials, the Iowa Department of Transportation required that contractors continuously monitor the temperatures and temperature differentials in the concrete placement to assure that the temperature differentials did not exceed 35 deg F. It was felt that if temperature differentials remained below 35 deg F, cracking would be minimized. The following is a summary of the background of the project, and what occurred during individual concrete placements. The following conclusions were drawn: 1) Side temperatures are cooler and more greatly affected by ambient air temperatures; 2) When the 35 deg F limit was exceeded, it was almost exclusively the center to side differential; 3) The top temperature increases substantially when a new pour is placed; 4) The use of ice and different cement types did seem to affect the overall temperature gain and the amount of time taken for any one placement to reach a peak, but did not necessarily prevent the differentials from exceeding the 35 deg F limit, nor prevent cracking in any placement; and 5) Larger placements have a greater tendency to exceed the differential limit.

Item Type: Departmental Report
Keywords: Bridge construction, Bridges, Construction, Fracture mechanics, Heat loss, Mass concrete, Temperature, Temperature differentials
Subjects: Transportation
Transportation > Bridges and tunnels
Transportation > Roads and highways
Transportation > Research
Transportation > Research > Concrete
Transportation > Design and Construction
ID Code: 16829
Deposited By: Iowa DOT Library
Deposited On: 07 May 2014 11:50
Last Modified: 11 Feb 2015 20:56
URI: http://publications.iowa.gov/id/eprint/16829