Hysteretic performance of novel grouted steel beam-column corner-connections for modular integrated construction

Abstract

In this study, three types of socket steel beam-column corner-connections with grouting for modular integrated construction are proposed and experimentally investigated. Six grouted and two ungrouted specimens were fabricated and divided into two groups: one group underwent monotonic loading and the other was subjected to quasi-static cyclic loading. A comprehensive comparison was conducted across all these specimens. The test results show that grouted bolted socket corner-connection with diagonal stiffeners can enhance its lateral stiffness, bearing capacity, structural integrity, and energy dissipation capacity. Conversely, the absence of diagonal stiffeners and bolts connecting the flanges of the floor and the ceiling channel beams led to a significant decrease to the bearing capacity, lateral stiffness, and energy dissipation capacity of the grouted bolted socket corner-connection. This underscores the critical role of diagonal stiffeners and bolts in these connections. Notably, weld cracking or tearing was a common failure, especially at the welds connecting the beam to the column and those linking the diagonal stiffeners. This failure highlights the importance of ensuring weld quality in practical engineering applications. According to Eurocode 3, all the specimens tested could be classified as semi-rigid connection, however, only the grouted bolted socket corner-connection with diagonal stiffeners met the criteria for full-strength connections.