Seahawks Practice Facility and Office Building Drilled Shafts into Rock

Date: May 2007

Owner: Vulcan Properties

Job: Seahawks Practice Facility and Office Building

Location: Renton, Washington

This project required drilled shafts to support the Seattle Seahawks Football teams’ Indoor Practice facility and Office Building.

The project is located in Renton, Washington between the I‐405 freeway and Lake Washington. The soils were saturated fills 30 to 55 feet deep overlaying hard rock. Pile Contractors installed 170 each 30” diameter drilled shafts that were cased to the rock and then drilled into the rock up to 15’ at each location.

The site was challenging due to the wet, muddy conditions and the very hard rock to be drilled.

The site was neighboring a log sorting and treatment facility with contaminated soils. All workers were HASWOP certified because of the potentially contaminated soils and waters.

Pile Contractors performed the drilling using a Hitachi EX400 and a Hitachi EX450 LoDril, a Sunward SA 20/70 Rock drill, and two Manitowoc Crawler Cranes.

The large free span facility is supported around the perimeter with 30” shafts, whereas the office facility is supported by conventional pile caps.

The general Contractor was Bayley Construction and this first class facility was completed on time and budget.