There are some proposed formulas by ACI, PCA, CEB-FIP and B3 which can be used to analyze column shortening, and each model has difference in calculating inelastic shortening that has influence on differential shortening.
This study performed a comparative analysis on parameter of each proposed formula for column shortening, and analyzed column shortening of two columns of 54-story C apartment in Haewoondae according to a proposed formula by each model. The analysis includes comparing the elasticity, creep, drying shrinkage shortening, the whole shortening, and differential shortening by each model with the column shortening analysis using the deterministic method, and the probabilistic method utilizing monte carlo simulation. And this study shows that the potential maximum shortening can be predicted using each formula by comparing shortening in each confidence interval with field measurement and probabilistic analysis. The results in this research are as follows.
1. As the result of comparing time-dependent creep rate and drying shrinkage rate with CEB-FIP, there was great difference on the day of completion 1000 days, between ACI and PCA, thus it was not appropriate to compare the influence of variable with probabilistic analysis, and it was also not appropriate to compare B3 model with variable of other models that had different formula of calculating creep shortening. Therefore, the researcher developed the method of analyzing probabilistic column shortening that is easy to compare the influence of variable with PCA model in previous studies.
2. As the result of deterministic analysis, it indicated that drying shrinkage shortening of PCA model were 1.6∼1.7 times greater than that of ACI model. Subsequent to slab installation shortening by PCA model was 114 ∼116%, and the total shortening was 129∼134%.
3. Differential shortening and the total shortening of PCA was 1.11∼1.14 times and 1.15∼1.27 times greater respectively as compared with ACI as the width of confidence interval was increased more subsequent to slab installation.
4. As the result of comparing field measurement with probabilistic analysis, the result by ACI model was closer to field measurement than the result by PCA. Furthermore, field measurement of ACI and PCA was between the mean value and the lowest value in 68.26% of confidence interval. Therefore this study can predict the potential maximum shortening without reference to applied formula.