Publish and Present
The Port of Long Beach has been expanding and modernizing several of its terminals and infrastructures to accommodate next generation ships and to become a leading green port. As a part of the modernization, a state-of-the-art fireboat station will be reconstructed at Pier F Berth 202. The proposed fireboat station consists of a pile-supported fireboat bay on the waterside and a fire station building on the land side of an existing dike slope. Being an essential structure, the fireboat station is designed to be operational during the building code Design Earthquake (DE).
The site for the fire station was developed several decades ago in several stages spanning various vintages by constructing multi-lift rock dikes and placing dredged fill materials possessing different characteristics. The fill materials indicate high liquefaction potential under the design earthquake, which potentially causes large lateral deformation and seismically induced vertical settlement. The buried rock dike, which may include potential armor rock and be susceptible to large lateral deformation during the seismic event, poses challenges to design and construction of the proposed fireboat station building that needs to remain functional during and after the earthquake event. Among various options considered and evaluated through value engineering, jet grouting was chosen as the most practical and cost-effective option to improve the ground to mitigate lateral slope deformation and to support the fire station building.
This paper summarizes the geotechnical investigation and site characterization that led to developing the jet grout improvement scheme. Details of other foundation options considered and engineering analyses and criteria that lead to selecting the jet grout improvement scheme are also discussed in light of past jet grout construction experience at the Port.