Study on Strong Earthquake Response Characteristics of Single‐Layer Spherical Latticed Shell Structure With Suspended Large‐Mass Equipment

ABSTRACT High‐level sports events and performing arts activities are imposing increasingly stringent requirements on the functional facilities of modern gymnasiums, which leads to a growing variety of equipment suspended beneath roof structures, such as center‐hung scoreboards, lighting systems, large‐sized audio equipment, and elevating stages. These large suspended masses are prone to violent swinging with significant impact effects during strong earthquakes. However, existing literature lacks sufficient research on the seismic response characteristics of long‐span roof structures with suspended heavy equipment. This study systematically investigates the natural vibration characteristics, seismic ultimate bearing capacity, and failure modes of a structural system comprising a suspended heavy mass, a single‐layer spherical latticed shell, and its lower supporting structure. The results indicate that the length of the suspension cables and the stiffness of the lower supporting structure have some influence on the mode shapes and natural frequencies of the structural system. Increasing the cable length or enhancing the support stiffness both lead to an improvement in the system's ultimate seismic bearing capacity. Notably, for a single‐layer spherical reticulated shell suspending large‐mass equipment, under unidirectional horizontal seismic wave input, the structure invariably fails due to dynamic strength failure; under three‐directional seismic wave input, dynamic instability failure occurs when the suspended equipment is attached to the upper platform, and dynamic strength failure occurs when not attached to the upper platform. The findings of this study provide a reference for the design optimization and safety assessment of long‐span roof structures with suspended heavy equipment.