Anchorage of links in slabs under fire conditions

There are only a few contradictory statements concerning anchorage of links with 90 degrees-standard bends in case of fire. Booklet 525 of the DAfStB (2010) recommends not to use these bends for a fire resistance class >= R90 on the fire stressed site of a plate. In booklet 600 of the DAStB (2012) anchorage of links and hat-shaped shear reinforcement in the compressive zone with 90 degrees-bends is described also as sufficient. In order to gain further experience tests with 90 degrees-bends and 135 degrees-hooks under fire stress were carried out at TU Kaiserslautern. Load behavior of the bends in cracked and noncracked section was investigated. If failure did not occur during the 120 min test period the remaining load capacity was determined in a pull-out test. Significant differences between the load behaviors of the analyzed bending molds were found and recommendations for practice have been worked out.