Überprüfung der zusätzlichen Regeln für ∅︁40 mm nach EC2 - Teil 1: Verbund und Zugstöße

Checking of additional rules for Ø40 mm according to EC2 - Part 1: Bond and lapped joints

The detailing of reinforcement of high impact structures can be simplified significantly by reinforcing bars with large diameters. According to the current European design and construction standard [1, 2] the valid maximum reinforcing-bar diameter is 40 mm. Bar diameters Ø40 mm are subject to technical approvals. In addition to the detailing rules for conventional bar diameters, tight restrictions regarding construction with large diameter bars (>Ø32 mm) exist [1, 2]. Since little investigation for the design and construction of structures with large diameter bars >Ø32 mm has been done, the bond behavior and the performance of lapped joints of reinforcing bars with large diameters were investigated at RWTH Aachen University within a research project funded by the German Federation of Industrial Research Associations (AiF). In this study, the transfer of design rules for laps for conventional bar diameters according to EC2 [1] and EC2/NA [2] to large diameter bars and the requirement of tight regulations for large diameter bars were analysed. Therefore, 28 beam-end tests and eight four-point bending tests were conducted to determine the effects of bar diameter, bond length, concrete strength, pressure transverse to the potential plane of splitting and confinement by stirrups as well as concrete cover.
This paper presents the test results of bond tests and tests on lapped joints with large diameters >Ø32 mm and a comparison with EC2 [1] and EC2/NA [2].