CDSM walls at Taxiway B under-crossing

CDSM provides excavation support &groundwater control
Completed CDSM panel exposed for viewing

CDSM improvement at Airport Dr. over-crossing

CDSMImprovement

CDSM provides ground stability for MSE walland embankment

Project Highlights•

A soil-cement gravity retaining wall, asoil cement foundation, and a soilcement-bentonite cutoff wall wereconstructed for two roadway undercrossings and one over-crossing.

•Over 68,000 cubic yards of loose,sandy fill and Bay Mud were improved
by CDSM soil improvement methods.

•Triple-shaft CDSM equipment wasused to improve soils to a depth of 43feet.

•CDSM construction exceeded all
geometric, strength, and hydraulicconductivity design requirements.

•Project Owner: Port of Oakland,Oakland, CA
Geotechnical Engineer: Geomatrix,Oakland, CA

Innovative Solutions to Today’s Geotechnical Demands

Airport Roadway Project, contracts ‘A’ & ‘B’, Oakland International Airport
Strength,qu (KPa)
02000

4000

6000

8000

01210000

The construction of the Oakland International Airport Roadway Project for the airport
expansion required the stabilization of subsurface soils for the construction of three grade
separation structures - two roadway interchanges and one intersection of a roadway andtaxiway serving the airport. Loose, sandy fill and soft Bay Mud were improved by Cement
Deep Soil Mixing (CDSM) for the construction of a soil-cement foundation under MSE(Mechanically Stabilized Earth) walls for a roadway over-crossing, a soil-cement gravity
retaining wall to maintain stability of a roadway under-crossing during and after a major
earthquake, and a soil-cement-bentonite cutoff wall for groundwater control.

Depth (m)3A test section was performed prior to full production to verify that the CDSM equipment,installation procedures, and mix designs would produce soil-cement and soil-cementbentonite with sufficient strength, uniformity, and permeability to meet the design intent.
Additional test sections were performed for the confirmation or modification of the mix
design and installation procedures to cope with the complex subsurface soil conditions
resulting from the historical development of the site. Test section results revealed that theCDSM cutoff wall, retaining wall, and foundation could be constructed to satisfy the design
criteria and that the supplemental test sections would alleviate the impact of the varying
subsurface soil conditions.

456789Test Section
Production

10

Over 60,000 cubic yards of CDSM ground improvement and over 8,500 cubic yards ofCDSM cutoff wall were constructed over a period of elevenmonths.

Triple-shaft CDSM equipment was used for ground stabilization and cutoff wall installation
to a maximum depth of 43 feet. Drilling depth, penetration/ withdrawal speed, shaft rotationand slurry injection rates were monitored on a real-time basis for accurate mixing control anda uniform mixed product.
Core samples were retrieved from the hardened soil-cement foundation and gravity retaining
walls for strength testing. Test specimens from the soil-cement-bentonite cutoff wall forstrength and permeability testing were retrieved by wet sampling. Acceptance criteria forunconfined compressive strength required an average of 150 psi at 28 days for groundstabilization and an average of 80 psi at 28 days for the cutoff wall. Hydraulic conductivityof the cutoff wall required a maximum coefficient of 1x10-6 cm/sec.
Pacific DivisionCorporate Headquarters
1660 Factor Avenue
San Leandro, CA 94577510-346-9840
510-346-9841 fax

Toll Free: 1-866-DEEPMIX
Website: www.raitoinc.com
Innovative Solutions to Today’s Geotechnical Demands

Atlantic Division6210 North King's Highway
Alexandria, VA 22303
703-718-0755
703-718-0744 fax