In the Master thesis, we considered two methods that are included in Eurocode 8-2 and Eurocode 8-3 standards, to estimate the rotational capacity of reinforced concrete columns. The numerical results were evaluated with experimental results. For this purpose, the experimental database was composed from various columns that were exposed to cyclic load tests. Columns with deficient structural details were of special interest.
Rotation capacity was determined on the basis of the full moment-curvature analysis. Obtained curvature was integrated along the length of the column. The fact that maximum curvatures are expected in the area of the plastic hinge, was also considered.
The estimation of the plastic hinge length is up to two times different with respect to the type of considered method. However, the difference of the estimated rotation capacity of the column is smaller in most cases due to larger estimates of the maximum curvature using Eurocode 8-2 method, where the length of the plastic hinge is smaller.
Numerical results of the square columns are a better match to the experimental results than the rectangular columns, however those estimates can be significantly larger than the actual rotation capacity, especially when considering columns with deficient structural details. Both considered methods are appropriate for the analysis of the columns that are constructed in accordance with the modern standards for the design of structures in the seismic areas. Due to frequent overestimates of maximum concrete compression strain, Eurocode 8-2 method should be modified somehow. To assess the rotation capacity of the columns with significantly deficient structural details, alternative procedure defined in the Eurocode 8-3 should be taken into account.
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