Title:
Biaxial Stress due to Shrinkage in Concrete Jackets of Strengthened Columns
Author(s):
Andreas P. Lampropoulos, Ourania T. Tsioulou, and Stephanos E. Dritsos
Publication:
Materials Journal
Volume:
109
Issue:
3
Appears on pages(s):
331-340
Keywords:
biaxial stress state; shrinkage; strengthening.
DOI:
10.14359/51683823
Date:
5/1/2012
Abstract:
The effect of restrained concrete shrinkage on the strength of concrete used to strengthen existing structures is investigated in this study. A series of compressive tests are performed on square prism concrete specimens where steel plates are placed in order to restrain free shrinkage. Results indicate that there is a significant reduction of concrete strength (20 to 30%) due to a biaxial stress state induced by the restrained concrete shrinkage. The experimental results are used to validate a numerical procedure proposed to simulate concrete shrinkage. A numerical investigation is then conducted on models that represent the concrete of a reinforced concrete jacket applied to an original column for strengthening purposes where the degree of restraint is different to that of the examined square prism specimens. It was found that that there is a further reduction of concrete strength (30 to 40%).