Pryout failure capacity of single headed stud anchors

Abstract

Concrete pryout failure mode, which occurs for relatively short and stocky cast-in headed studs or post installed anchorages, has been investigated only to a limited extent in the past. The increasing use of such anchorages in engineering practice emphasizes the need to clarify the pryout failure mechanism and to formulate design rules that assure safe and economical structural design. Currently used design provisions are based mostly on analysing push off test data, which were focusing on composite beam design. The database (Jebara and Ožbolt in Vergleichsanalyse von Bemessungskonzepten fur Querbelastung und Scherversuche mit ruckwartigem Betonausbruch (pryout). (Literature review of design concepts for shear loaded tests with pryout failure), Internal Report/November 2011) including recently reported shear tests is lacking in pryout in-the-field tests with systematic variation of anchor embedment depth and diameter. In order to clarify the behaviour of cast-in headed studs and anchor bolts, shear tests were performed on single cast-in headed studs (Jebara and Ožbolt in Tragverhalten von angeschweistem gedrungenen Kopfbolzenverankerungen in der Flache unter Querlast, experimentelle Untersuchung, (Bearing mechanism of stocky studs in-the-field under shear load, experimental Investigation), Internal Report/November 2013). In the present article the experimental results, pryout failure mechanism and proposed pryout capacity equation for single anchor under pure shear load are presented, discussed and compared with current design formula.