This grade separation was an integral part of the Port of Los Angeles’s $1 billion Pier 300/LAXT Expansion. It is also on of the first major projects for the future Alameda Corridor, which will take all rail traffic from the Ports of Long Beach and Los Angeles to the main rail switchyard next to downtown Los Angeles. The grade separation is necessitated by the huge increase in rail traffic caused by the Port of LA’s expansion, while the truck traffic on the Port’s streets remains heavy and constant. The project consisted of two double span steel railroad bridges with concrete substructures, six reinforced earth retaining walls, 200,000 cubic yards of embankment fill, 2 miles of various utilities (storm drain, waterline, telephone), design/build train signaling system, 2 miles of new paved roadway and a storm water pump station. Most of the site was unstable due to the combination of a high ground water table with very weak soil characteristics. In order to alleviate this problem, 2300 each, 3’ diameter stone columns were installed 8 feet on center to consolidate the weak soils and to provide a drain to reduce the potential for soil liquefaction.

This project was very difficult to construct due to the existing truck and rail traffic and the fact that this traffic could not be interrupted except for a few hours at a time. In order to accomplish this task, we constructed seven temporary railroad shoo-flys and 2 truck detours. After the POLA awarded Shimmick/Obayashi, JV the job, they asked us to find a way to complete the project six months early. We accepted the challenge and delivered the completed project on the requested date. This involved numerous design changes, fast track scheduling, and many hours of overtime work. Most of the major design changes were presented and developed by Shimmick/Obayashi. These changes not only reduced the time of construction, but they also reduced the total costs of completion to the Port of Los Angeles.