Title:
Shrinkage In Concrete Pavements
Author(s):
Publication:
CIA
Volume:
Issue:
Appears on pages(s):
Keywords:
DOI:
Date:
2/13/2011
Abstract:
Volumetric changes in concrete are unavoidable and occur from the onset of casting. While the causes behind these changes have been the subject of considerable research, little information is available quantifying the effects immediately after casting. This paper presents some results from ongoing experiments to investigate early and later age shrinkage of concrete pavements. The work is part of a joint research program between the APMCA, MRD (Qld) and the University of Queensland. The experiments involve instrumented slabs under both laboratory and field conditions. Soft vibrating wire strain gauges were used to measure strain and temperature changes at various depths and locations within the slabs. The results identify two distinct mechanisms driving early volumetric change, the first being pore water suction, the second being thermally induced strain. The results indicate how cracks can initiate early in the life of a pavement. The paper also considers later age drying shrinkage. It is shown that this may not develop according to the codified model1, 2.