Characteristic concrete compressive strength of existing structures—Evaluation of <scp>EN</scp> 13791:2019 for small sample sizes
Rabea Sefrin, Christian Glock
Abstract
Abstract In the sense of resource‐efficient handling of existing structures, conversion should be given priority over demolition and reconstruction of buildings. Accordingly, the assessment of existing structures is becoming increasingly important. Until now, the characteristic concrete compressive strength as one of the most important factors for the evaluation of existing structures has been determined at European level according to EN 13791:2007. Today, the new EN 13791:2019 replaces EN 13791:2007. Especially for small sample sizes of drill cores (3 ≤ n ≤ 7), the introduction of EN 13791:2019 results in significant changes for the determination of the characteristic in situ concrete compressive strength. In addition, there is only limited background information available for the statistical robustness of the new methods. Therefore, the methods for the determination of the characteristic concrete compressive strength of existing structures according to EN 13791:2019 have been evaluated with the help of an existing drill core database established at the TU Kaiserslautern.