Bravern II, Bellevue, WA (2007)

Shoring System: Temporary Soil Nailing and VENIS

Client: Malcolm Drilling Company Inc.

General Contractor: Skanska USA, Inc.

Shoring Contractor: Malcolm Drilling Company Inc.

Shoring Face Area: 58,370 Square Feet

Wall Depth Range: 45 to 83 feet

Status: Completed 2007

Phase II of the massive 6-acre site in downtown Bellevue included excavation to 84-ft below grade along existing city streets and the underpinning and lateral support of the existing high-end Meydenbauer Center along the south side of the excavation. Standard soil nailing was utilized throughout the walls that supported the city streets, with up to 15 rows of soil nails up to 59-ft in length, and a 5-inch temporary shotcrete facing; while a prestressed vertical element and nail integrated support system (VENIS) was utilized along the supported building. As expected, movements along city streets reached about an inch, while the movements at the Meydenbauer Center were largely imperceptible, but in some areas up to less than 1/4 of an inch.