Experiment and analysis on reinforced concrete spatial connection in diagrid tube

Summary A diagrid system can be used as exterior tubes comprising creative high-rise structures together with core tubes. This system has four or more facade diagrid walls connected perpendicular to each other in a plane and includes spatial intersections at its corners. These spatial connections can provide integrity to the entire diagrid tube system. To analyze the influence of the volumetric ratio of the stirrups and loading patterns on the ultimate load-bearing capacity of the spatial connections, four specimens were statically tested until failure in a three-dimensional setup. The expansions and compressive deformations were also recorded and analyzed. The results indicate that this connection satisfies the requirement of ‘strong connection, weak elements’ and that the use of transverse stirrups can effectively confine the expansion of core concrete in the joint region. Based on the performance of reinforced concrete under axial compression, an equation was proposed for evaluating the bearing capacity of spatial connections in diagrid systems for use in actual recommendations. Copyright © 2015 John Wiley & Sons, Ltd.