The Effect of Internal Restraint of Rebar in Shrinkage Stress Analysis of Concrete Slab in Multistory Building

고층건물 콘크리트 슬래브의 건조수축응력 해석에서 철근의 구속효과

In this study, a practical method of shrinkage stress analysis on concrete slab in multi-story building is proposed, which considers both internal restraint and external restraint variation resulting from construction sequence. The shrinkage stress due to external restraint is obtained by multiplying relaxation coefficient to elastic shrinkage stress. The additional shrinkage stress due to internal restraint is obtained by residual strain of the elastic analysis. A verification example was analyzed and compared by the proposed method and commercial analysis program that is capable of time-dependent analysis of concrete. The results of 10-story example building show that the internal restraint of reinforcement increases the shrinkage stress considerably at the slabs under loose external restraint.