Southern California Gas Company Pipe Bridge Project

The firm performed a peer review (aka served as owner’s engineer) of this bridge and foundation design performed by others. This long-span bridge was unique in that it is located very close to the San Andreas Fault, is in a steep canyon subjected to landslides, etc. This review identified major deficiencies in the structural seismic design performed by others, including, among other things:

  • Improper use of boundary conditions that resulted in significantly undersized members
  • Failure to consider landslide loading on foundation elements, resulting in significantly undersized structural members
  •  Use of bracing systems not allowed by AISC 341, Seismic Design Manual
  • Use of members that were not “seismically compact”
  • Use of bracing members that did not meet seismic slenderness requirements
  • The strength of bracing connections did not meet the requirements for ordinary concentrically braced frames to employ amplified seismic loads
  • The results of our peer review required a complete redesign of the bridge and foundation.