Title:
Time-Dependent Deflection and Deformation of Reinforced Concrete Flat Slabs- An Experimental Study
Author(s):
R. I. Gilbert and X. H. Guo
Publication:
Structural Journal
Volume:
102
Issue:
3
Appears on pages(s):
363-373
Keywords:
cracking; creep; deflection; flat slab; reinforced concrete; service load; shrinkage
DOI:
10.14359/14407
Date:
5/1/2005
Abstract:
An experimental program of long-term testing of large-scale reinforced concrete flat slab structures is described and the results from tests on seven continuous flat slab specimens are presented. Each specimen was subjected to sustained service loads for periods up to 750 days and the deflection, strains, extent of cracking, and column loads were monitored throughout. The measured long-term deflection is many times the initial short-term deflection, due primarily to the loss of stiffness associated with time-dependent cracking under the combined influences of transverse load and drying shrinkage. This effect is not accounted for adequately in the current code approaches for deflection calculation and control. The results form a benchmark set of data from which more reliable deflection calculation procedures can be developed and calibrated.