Abstract
Cracking of concrete slabs at sawcut notches is a major concern in the early stages of construction. Several factors affecting crack initiation are material strength parameters, method and quality of curing, slab/subbase stiffness, and concrete shrinkage and creep. Early age creep and shrinkage also appear to be key factors of stress and cracking. Experiments were run to provide insight on the effect of shrinkage and creep on crack developments. The results were useful in evaluating the behavior of concrete and the development of cracking at sawcut notches. The German Cracking Frame was used to provide restraint and to initiate cracking at an artificial notch. The cracking occurred during the concrete's early age strength development, due to creep and shrinkage. The cracking frame tests were conducted under constant temperature and relative humidity conditions in the laboratory. This research also examines the role of creep and shrinkage under field conditions, lative to the control of cracking due to sawcutting of newly constructed concrete slabs. It can be concluded that the development of creep strain in concrete affects its cracking tendency. The data that were collected seem to suggest that, after the creep of the concrete diminishes sufficiently, a greater cracking tendency at the sawcut notches results.
Vepakomma, Shilpa (2002). Characterization of cracking restraint at sawcut joints using the German Cracking Frame. Master's thesis, Texas A&M University. Available electronically from
https : / /hdl .handle .net /1969 .1 /ETD -TAMU -2002 -THESIS -V44.