The Pacific Amphitheater’s new entry is complete!Apr 21 2016 · 0 comments · Cultural, Nishkian Chamberlain, Tenant Improvement ·0
The Orange County Fairground is host to many events each year and one of the biggest venues there is the Pacific Amphitheater. Nishkian Chamberlain is proud to be part of the design team that was tasked to bring a new entrance structure and entryway plaza to the venue.
The Pacific Amphitheater has for years hosted major entertainment events in its 5,000+ seat amphitheater. The venue is tucked into existing grade with seating directly on ground and the stage set into a natural depression. At the back of the seating was a 35-foot tall soil berm that provided the outside boundary of the venue and also provided a natural sound barrier. All of these elements helped with keeping initial costs for the venue down when it was originally built. However, one element that was always missing from was a focal entry point and plaza. The entry into the venue had always come from the back or side of the amphitheater and lacked a connection to its surroundings.
In 2012, our office began development with a design team lead by MAKE Architecture (makearch.com) of major modifications to the venue to update the Pacific Amphitheater and address the issues. These modifications included changes to the soil berm to allow a new entryway into the amphitheater, new entry structure, new entry plaza, new ticket booths and restroom facilities and a widening of the amphitheater upper walkway.
The soil berm modification was a major structural design component and required a unique and different design to meet the challenging site. The soil berm required 35 tall retaining wall ls at its peak with a curved radius and varying heights along its length. After investigation of several retaining wall options, a permanent tie-back retaining wall system was chosen for its efficiency and limited requirement for excavation. Steel soldiers piles are located at approximately 8-feet on center over the wall length with variations in design for the soldier pile from cantilevering piles to piles with up to two tie backs. Soldier piles are were set in concrete slurry caissions and then chipped down as soil was removed. A shotcrete wall was utilized as the front face of the system and connected to the steel soldier piles with welded shear studs and reinforcing. Careful coordination with the Project Architect was required on the wall height adjustments, waterproofing system and finished joints to ensure an architectural concrete surface.
The entryway structure was also a significant element in design. The structure was intended to connect the venue plaza with the Amphitheater inside. A very tall floor to ceiling structure was created with steel framing with special attention to Architectural finishes. The structure contains special steel moment resisting frames in the transverse direction of the building and special concrete masonry unit shear walls in the longitudinal direction of the building. An architectural diagrid at the front of the building provides a unique architectural viewpoint which was structurally supported with a diagonal tube steel grid. A steel moment frame system supported the structure and was isolated from the diagrid.
The new Pacific Amphitheater opened in 2015 and with the improvements is once again providing a major venue for entertainment in Orange County.