Seismic Behavior of Welded Hospital Piping Systems

This paper presents findings from shake table experiments on cable-braced and unbraced welded hospital piping systems. The research identifies the capacity characteristics of a hospital piping system with and without bracings as well as the system’s weak points. The system was tested to the ICBO AC156 acceptance criteria for nonstructural components. The input motion of 1g was amplified to almost 2.6g at the top of the braced and unbraced piping systems. There was no significant damage to the piping system due to the high displacements and accelerations. Two of the eleven braces failed at the highest input excitation, the 21⁄2” diameter vertical hanger rods failed during the unbraced tests, and a flanged connection began to leak during a pushover test. Preliminary results show that the braces limited the displacements, but they did not significantly reduce the accelerations of the system.