Title:
Concrete Vibration--What's Adequate?
Author(s):
Lars Forssblad and Stig Sillstrom
Publication:
Concrete International
Volume:
17
Issue:
9
Appears on pages(s):
42-48
Keywords:
chlorides; compressive strength; density; freezing and thawing; permeability; vibration; voids; water; Construction
DOI:
Date:
9/1/1995
Abstract:
Guidelines regarding the amount of concrete vibration that is adequate for various casting conditions are proposed as the result of field studies in Sweden. The amount of vibration has been defined as the "vibration effort," equal to the effective time of vibration per concrete volume as measured in seconds per cubic meter or cubic yard. For various vibration efforts, the density, compressive strength, resistance to freezing and thawing in slat solution, water permeability, and chloride permeability were determined on cores drilled out from the hardened concrete. Freeze-thaw tests resulted in reduced frost-resistance close to vibrator insertions. Meters to record the running times of internal vibrators have been developed.