Design optimization to increase the (buckling) stability of concrete columns

摘要

In 2014 and 2015, concrete columns were tested under axial compression in the Otto-Mohr-Laboratory of Dresden University of Technology. In comparison to columns with the same volume and a constant rectangular cross section, a 25% increase in buckling resistance was attained with an optimized shape. The shape of a column can be optimized in both the longitudinal and the transverse direction. Both aforementioned possibilities were tested separately in two experimental series; the results of such tests were used to verify the accuracy of the theoretical calculations. Based on these calculations and considerations, it was determined that an even larger increase of the buckling load is possible, for example, by combining both form influences (cross section and shape in longitudinal direction). A literature review regarding the optimization of axially loaded columns was conducted in 2012 and 2013. First, the current study gives an overview of the mathematical results. Subsequently, it presents the column test results in detail. Both simply supported columns and columns with fixed ends were tested. All columns were designed with ultra-high-performance concrete. The outcomes of the experiments are provided and discussed. Additionally, the measured values are compared with the calculated values.