Development of new punching shear reinforcement for footings

• Applicant: Professor Dr.-Ing. Josef Hegger
• Subject Area: Structural Engineering, Building Informatics and Construction Operation
• Term: from 2014 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 249087059

According to the findings in the previous project, the punching force cause different failure mechanisms in slender and compact footings. While in slender footings the slab rotation controls the fracture kinematics, in compact footings a translational movement of the punching cone is also determining the fracture mechanism. Due to the crack formation and fracture geometry, an inclined punching shear reinforcement system seems to be more effective than vertical bars.The aim of the knowledge transfer project is the development of a specifically optimized punching shear reinforcement system especially for foundations consisting of inclined an vertical reinforcing bars. Compared to conventional punching shear reinforcing elements it is easy to use and leads to a 20-25% higher punching capacity with a low material usage. Along with the application partner, theoretical and experimental investigations are carried out in order to develop an adapted punching shear reinforcement system adjusted to the fracture mechanism of slender and compact footings together with an associated model. The punching tests are also employed for calibration and validation of engineering models.

• DFG Programme: Research Grants (Transfer Project)
• Participating Institution: HALFEN GmbH