DESCRIPTION

The project consists of the construction of a High Bay Freezer Warehouse addition – immediately adjacent to the existing warehouse. Structural loads for the building shell were light to moderate with max typical column loads of 50-150 kips and typical wall loads of 2-5 kips. Slab loads, however, were significant – in the range of 1,000 psf.

CHALLENGE

Soil conditions consisted of the following:

While traditional shallow foundation support of the building shell was possible, the slab loading created long-term settlement concerns for the addition, and raised concerns of settlement of the existing structure. Surcharging, which was employed for the original warehouse construction, was not a viable option because of the aggressive schedule, and the potential to cause settlement of the existing warehouse.

SOLUTION

Geopier Rigid Inclusions were selected to solve the problems of settlement control of the heavily loaded slab load founded over extremely soft/loose soils, and to isolated the stresses from the new construction so they would not impose loads that could cause settlement of the existing warehouse. High capacity GeoConcrete Columns supported the slab, and lower capacity Grouted Impact Piers supported the columns and walls. The GeoStructures team worked closely with the General Contractor and Structural Engineer to incorporate the required 2-4 feet of fill into a load transfer platform to make the project easy to construct for all parties, as well as optimize the slab design.

Grouted Impact Pier elements being installed for footings in the foreground. While GeoConcrete Columns were being installed in the background for floor slabs adjacent to the existing warehouse

Mixing the two Geopier Rigid Inclusion systems proved to be the most economical system. 732, 12-inch diameter GeoConcrete Columns installed to depths of up to 53 feet and 255, 16-inch diameter Impact Pier elements were installed to depths of up to 49 feet in 43 days. Production rates exceeded the project schedule requirements.

Ability to install piers within approximately 5 feet of the existing warehouse.