DESIGN METHOD OF POST-INSTALLED ANCHORAGE GROUP SUBJECTED TO BENDING MOMENT AND SHEAR

Existing researches on the multiple-anchor steel-to-concrete connection, the strength of which is controlled by the strength of the anchor steel, are used to develop a revised method for the strength prediction of post-installed fastening connections subjected to bending moment and shear. Based on the assumption that all anchors take up shear load, the revised method considers that only the row of most stressed anchors in the tension zone are needed to meet the elliptical interaction of tension and shear capacity requirement during the design process of anchorage group under the action of shear and bending moment. The static and dynamic behavior of the connection, in which steel members are attached to concrete by boned-in reinforcement, have been tested due to eccentric shear loadings. The experimental results show that the outermost row of tension reinforcements reach their yielding strength prior to failure of the connection and slight concrete cone failure occurs under ultimate load. The significant deformation guarantees ductile behavior of the connection. The yielding capacity of the connection under reversed cyclic loading is lower than that of static condition. Thusly, the predicted capacity in aseismic design is advised to multiply by a reduction factor of 0.8. Compared with experiment results, the revised method presents satisfactory accuracy to be used in practice.