An existing coal-loading pier located in Norfolk, Virginia was completed in 1961 for the purpose of loading ocean-going ships with coal for export throughout the world. The size of the ships that could be fully loaded at this facility was limited to the depth of the mud line adjacent to the loading pier. It was determined that dredging adjacent to the pier would provide an increase in loading capacity and productivity for pier operations.
Since the existing pier is supported by concrete piles, there was a concern that the lateral stability of these piles would be significantly reduced by the sloughing of surrounding support soils into the adjacent dredged areas. To prevent this, a wall of some kind would be required to retain these soils and ensure the integrity of the existing piles. After considering a number of options, the jet grouting technique was chosen as the method to be used to create a wall between the existing rows of concrete piles. At a contract value in excess of $ 1,800,000.00, this project is the largest jet grouting application to date in the U.S.
Analysis of data obtained from the extensive project test program, verification section, and production work indicate that the twin stem jet grouting system, in what is believed to be its first U.S. application, yielded a more consistent, better quality end product than was produced with a single stem jet grouting system, in addition to substantial production rate increases.
Jet Grouting to construct a Soilcrete wall using a twin stem system