Home to the Major League Soccer’s San Jose Earthquakes, Avaya Stadium is a soccer-specific stadium that opened in early 2015. Formerly the site of an FMC Corp. facility, the stadium is located just two miles from downtown San José and is next to San José International Airport. Langan provided geotechnical, seismic, environmental, and construction monitoring services for the project. Our team observed and tested mass grading, installation of foundations, preparation of sub-grade for slab-on-grade, and backfill of underground utility trenches and pre-existing concrete obstructions. Langan also assisted the construction team to comply with the Department of Toxic Substances Control’s (DTSC) approved Soil Management Plan, and evaluated potential vapor intrusion risks from residual volatile organic compounds.
Solutions to Challenges
Langan was a key member of the project team, working closely with Magnusson Klemencic Associates and Devcon Construction. The project had two significant challenges.
The first challenge we encountered was the weak compressible layers in some areas of the site. To address these subsurface conditions, we developed design criteria for an economically efficient foundation system that could adequately perform under the design loads with acceptable settlements.
We faced our second challenge during the grading and installation of the underground utilities: buried, pre-existing obstructions. These obstructions consisted primarily of old concrete footings, drilled piers, pier caps, and below grade basement structures. Due to the lack of information regarding these obstructions, our team thought outside the box to come up with effective measures to deal with them without adversely impacting the construction progress.
Underground obstructions are common – but not to the degree and depth that we found in this project. There were numerous obstructions, with many extending below the groundwater table. We implemented appropriate grading requirements to properly place and compact fill in the openings after removing the obstructions.
Our environmental team also had to ensure the project complied with DTSC’s Soil Management Plan. To that end, we evaluated potential vapor intrusion risks from residual volatile organic compounds, coordinated with DTSC on the plan’s implementation, and observed and documented construction activities to assure compliance with DTSC’s requirements.
We overcame these challenges by being flexible in our approach and innovative in our solutions. One of our favorite moments was seeing the tall sections of the structural steel being placed—verifying our successful work underneath. Another great moment was watching the Earthquakes’ first game at the inaugural soft opening event—it was great to see such a wonderful landmark structure become reality.
Answer provided by Scott Walker, PE, GE
Scott provides project management, engineering analysis, construction observation, and subsurface investigation services for various projects throughout California and southwestern Montana. His experience includes performing geotechnical services as well as staff supervision during investigations and construction for schools, hospitals, residential and commercial buildings (including high rise structures), sports facilities, industrial projects (including bridges, roadways, utilities), and resort development.