Fatigue Performance of Stiffened Pole-to-Base Plate Socket Connections in High-Mast Structures

AbstractFatigue performance of stiffened pole-to-base plate socket connection in high-mast lighting structures was evaluated by experimental and analytical studies. In absence of sufficient experimental data, constant amplitude fatigue limit (CAFL) of longitudinal stiffener terminations on pole walls is classified as Category E′ in the existing American Association of State Highway and Transpiration Officials (AASHTO) specification. Fatigue performance of this connection in the thin-walled tubular structures is controlled by localized secondary bending stress, the magnitude of which depends on the relative stiffness of the connecting elements. Ten full-size high-mast specimens having stiffened socket connection were tested under constant amplitude reversal loading to determine the fatigue resistance of this connection in finite and infinite life regimes. The specimen design was optimized by parametric finite-element analysis (FEA) and local stress approaches. FEA results were verified by conducting static...