Title:
Time-Dependent Deflection of Slab Affected by Construction Load
Author(s):
Hyeon-Jong Hwang, Hong-Gun Park, Geon-Ho Hong, Jae-Yo Kim, and Yong-Nam Kim
Publication:
Structural Journal
Volume:
113
Issue:
3
Appears on pages(s):
557-566
Keywords:
construction load; cracking; flat plate; long-term deflection
DOI:
10.14359/51687943
Date:
5/1/2016
Abstract:
Long-term deflection is a critical issue in the design and construction of long-span flat-plate slabs that have become popular for tall buildings. In the present study, a numerical analysis method was developed to predict the long-term deflection of flat plates. In the proposed method, variations of construction load, moment redistribution due to slab cracking, and long-term effect of creep and shrinkage were addressed. The proposed method was applied to slabs in two actual multi-story buildings under construction. The predicted long-term deflections were compared with the on-site measurements. The results showed that the immediate deflection due to the construction load significantly increased the long-term deflection, and the predictions agree with the measurements.
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