Experimental and Analytical Studies of Hospital Piping Assemblies Subjected to Seismic Loading

Abstract

The seismic characteristics of welded and threaded hospital piping assemblies were investigated with and without seismic restrainers under various intensities of seismic loading using a biaxial shake table. Experimental results showed that the restrainers limited the displacements; however, they did not reduce the acceleration responses. No leakage was detected in the welded assembly up to a drift ratio of 4.3%; however, threaded piping suffered minor leaks at a drift ratio of 2.2% and experienced connection failure at a drift ratio of 4.3%. A simplified computational model was developed and calibrated with experimental data using SAP2000. The effective stiffness of the seismic restrainers was determined to be 10% of full stiffness due to their initial slack. The analyses showed that the dynamic response of the piping system as braced in these experiments with similar boundary conditions was predominantly kinematic with minimal inertial effects.