Elliptical Jet Grouting: An Innovative, Viable, and Effective Solution: The Example of the Bottom Plugs for the SELA Projects in New Orleans, LA

As part of the Southeast Louisiana (SELA) drainage program, designed to reduce flood damages in the City of New Orleans and surrounding parishes, several individual projects required ground improvement work to replace the soil between parallel lines of sheet piles with a soil-cement mass, having the purposes of both eliminating under-seepage, thus creating a so-called bottom plug, and providing structural support for the underground concrete box culverts, as well as providing a stable and dry work platform for the subsequent operations of excavation, forming, casting, etc. The U.S. Army Corps of Engineers (USACE), New Orleans District, selected the jet grouting technology for the construction of the bottom plugs. For the contracts it was awarded, the specialty geotechnical contractor proposed to accomplish the task utilizing their proprietary and innovative elliptical bi-fluid jet grout technology. This technology, introduced for the first time in an actual production work in the U.S., offers great benefits in terms of productivity and flexibility, while always maintaining the necessary quality of the work. It may also provide important environmental benefits in terms of reduced binder and transport needs. This paper will present in detail the main features and advantages of the elliptical jet grouting technology, and will provide supporting evidences from the successfully completed SELA-22 and the ongoing SELA-26 projects in New Orleans.