Anticipated Soil Mixing Volume: 58,454 CY of soil up to 31 feet deep
Description of Work:
The principal purpose of the project was to use soil mixing techniques to stabilize and solidify soils that have been impacted by wood treating chemicals with a cement and water grout. The two soil mixing techniques used were bucket mixing utilizing a Kobelco 350 excavator and single auger soil mixing utilizing Geo-Solutions’ Delmag RH 18 drill rig. Bucket mixing was utilized in areas where the final treatment depth was no greater than 20 ft. below the ground surface (BGS). Single auger soil mixing was utilized in areas where the final treatment depth was approximately 21 to 31 feet BGS.
The site soils consisted mostly of poorly graded sands. The in situ stabilization and solidification extended into a clay layer. Using site soils and a cement and water grout, the final in situ solidified material had an unconfined compressive strength of greater than 50 psi and permeability slower than 1 x 10-6 cm/sec. During soil mixing operations, Geo-Solutions maintained all erosion and sediment controls along, handled spoils, and graded the site.
Geo-Solutions was able to minimize cost by performing most of the work during a slower construction season and by using owned equipment. The following owned equipment was used: Delmag RH 18 drill rig, continuous mix batch plant, 60 ton cement silo, forklift, man lift, and all associated pumps and hoses. Geo-Solutions rented excavators and a bull dozer from a local supplier.