Author(s): Christian Sundberg

Linked Author(s): Christian Sundberg

Keywords: Hydraulic; Structures; Differential; Settlement; Seismic

Abstract: A focal point of seismic resilience occurs at hydraulic structures where below ground pipelines enter and exit reinforced concrete walls. This interface has long been recognized by engineers as a location that suggests accommodation of movement due to differential settlement. Pipeline seismic forces due permanent ground displacement, adversely affects structural design due to large bending moments, and shear forces imparted to hydraulic structures. The moments and forces can be substantially reduced by introduction of flexibility into the piping system which has a positive result on design of hydraulic structures. This paper will address the benefits of the addition of grooved, flexible yet restrained couplings, located at below ground piping/structure interfaces at hydraulic structures. Piping stress analysis, using CAESAR II software that utilizes a beam style FEA analysis, was performed on 24”, 48”, 72”, and 96” steel pipe sections subject to a rigid restraint on the left replicating the structure wall, various distances to various seismic lateral displacements (1”, 2”, 3”, 4”) and, 100 psig water pressure. The moments on the fixed end (structure wall) were calculated with and without pairs of flexible couplings to show the benefit and reduction in bending moments and shear forces on the structure wall through the use of flexible yet restrained couplings

DOI: https://doi.org/10.3850/IAHR-39WC2521711920221602

Year: 2022