San Antonio River Tunnel Inlet Physical Model Development and Study

Abstract

In October 1998, the San Antonio River Tunnel project experienced its largest flood to date. During that event the Removable Splitter Wall (RSW) vortex suppression device was damaged: The lower two panels apparently vibrated and broke due to fatigue. The RSW was comprised of nine 25-ft long, by 6-ft high and I1-in thick panels. Each panel was constructed of reinforced concrete with a C-channel framing the each edge. According to Corps of Engineers staff, structural engineers have determined that the failures, each at approximately the third points, were characteristic of a fatigue failure (Photo 1). From Photo 2 of the panels being lifted from the inlet shaft, the panels broke approximately 9 feet from the downstream end. The points of failure were also reported to coincide with the lifting holes for the panels.