University of Alaska Southeast John R. Pugh New Residence Hall
RESPEC served as a subconsultant to this project’s architect by providing civil, geotechnical, mechanical, and structural engineering services for a new, 60-bed residence hall with future growth planned to a minimum of 120 beds.
The new residence hall presented the RESPEC structural design team with many challenges and opportunities for innovative design. Major challenges included designing for construction in an extremely rainy climate, ensuring proper foundation support despite sloping terrain and varying soil conditions across the site, supporting complex rooflines, and incorporating changes to the construction scope late in the design process. RESPEC engineers worked diligently with the design and construction team members to complete this unique facility on schedule while exceeding the client’s expectations.
With three structural systems used in the building and four seismically separated portions of the facility, creativity and attention to detail were needed. RESPEC’s approach was to design load-bearing, cold-formed steel structures that sandwiched the central, structural-steel-gathering structure and provided seismic joints between the independent structures. The front entrance canopy, which was framed in glue-laminated timber (glulam), was seismically separated from the warm building structures. The three structural systems were selected to provide the best fit for the architectural layouts, efficiency of materials, and sustainability considerations.
The site geology contained bedrock surfaces and deep lenses of organic material, and a diligent subsurface investigation was required to identify these two site conditions. Site-investigation methods for the four-story residence hall included machine-dug test pits and hand-exploration methods to map the bedrock surface and model that surface in Civil 3D site-design software. RESPEC was particularly concerned that half of the building would be bearing on bedrock surface and the other half on an engineered embankment surface. The building siting with these varying site conditions included close coordination with the structural engineer, architect, and owner.
The civil engineering design for this 1-acre, undeveloped, sloping, forested site included clearing and grubbing as well as site preparation for the building foundation. An extension of the domestic- and fire-water supply was provided. Design components also included a new sanitary sewer system that connected the site to Glacier Highway; a new underground storm drain system; erosion- and sediment-control plans; and traffic-control plans for the Glacier Highway sewer connection. Challenges inherent to the varying soil conditions required that the bedrock surfaces be modeled to determine the limits of the rock excavation that was required to safely support the building foundation. The site work was designed and permitted to be constructed in two phases. Close coordination with the design team was maintained throughout the project design phase to ensure that the building footprint and foundation system aligned with the bedrock excavation.
International Building Code special inspections were performed during the construction of the new facility. These inspection services included earthwork, reinforced concrete, epoxy grouted anchors, structural-steel bolts, structural-steel welding, and cold-formed steel. RESPEC engineers also performed water-sample testing per City and Borough of Juneau requirements, compaction testing within the Alaska Department of Transportation & Public Facilities right-of-way for the sewer manhole installation, and observation of water- and sewer-pressure testing procedures per the project specifications.
The mechanical systems design included air-source heat pumps with an electric boiler backup heating plant, radiant floor heating, heat-recovery ventilation, low-flow plumbing fixtures, wet sprinkler and standpipe systems, a propane emergency generator, and direct digital controls.