Anchorage Performance of Button-head Steel Bars in Grouted Reserved Holes in the Precast Shear Wall

To study the anchorage performance of button-head steel bars in grouted reserved holes in the precast shear wall, pull-out test of 27 specimens with button-head steel bar and 24 specimens with straight steel bar were carried out. Concrete strength, recycled concrete, reinforced bar diameter, anchorage length, and reserved hole diameter were considered as the main factors. Test results show that when button-head steel bar anchors 150mm in high strength grouting material, its ultimate bond strength reaches more than 1.8 times of straight steel bar. Anchorage length of this button-head steel bar is suggested as 0.6 l _ab; high strength grouting material has good bonding properties with both ordinary concrete and recycled concrete hole surface. 50mm can be selected as the reserved hole diameter in precast shear wall.