Manhattan Underground Park Exhibit Features Arup Daylighting System
Beginning September 15, "Imagining the Lowline," a free exhibition in Manhattan's Lower East Side, will showcase Arup's research into a proposal for the world's first underground park. The exhibit demonstrates how the team's daylighting system for collecting sunlight and channeling it belowground can create an attractive public space and enable plant growth.
Arup has been heavily involved in the project since approaching the architects to enquire about partnering with them to provide technical services. The firm's multidisciplinary team - structural, mechanical, electrical, plumbing, and geotechnical engineers; fire/life safety, code, and acoustic consultants; and lighting and tunnel designers - has provided critical feasibility studies and innovative explorations of design possibilities.
"There's a huge amount of innovation in this project," said project director Craig Covil. "How do we collect daylight, how do we bring it underground, how do we match its intensity to what both plants and humans need down there? Add in all the other environmental issues with regard to noise and vibration, temperature, humidity, and people flow, and there are quite a few things to challenge us."
The current exhibit transforms an abandoned warehouse in the Lower East Side into a life-size replica of the proposed Lowline. The centerpiece is a 35-foot-wide canopy with 6 "sunbeamers": devices that reflect sunlight into a parallel column, then down a highly reflective tube. From there, lenses in the canopy redistribute the light above a mock-up of a park containing plants that can be cultivated in low light conditions. The system is the result of months of design, modeling, and testing by Arup's lighting team.
The firm's structural engineers created a steel frame that straddles the roof's skylight to support the aluminum canopy (comprising over 500 unique laser-cut aluminum pieces) and sunbeamers. The frame bears on the roof through multiple layers of timber and sand, eliminating the need to anchor into the existing structure. To ease construction, segments were fabricated in the shop and assembled onsite.
The exhibition also features a 3D immersive ambisonic audio installation created by the firm's acoustic consultants. Twenty-four targeted loudspeakers and four subwoofers play a sound art composition by acoustician Anne Guthrie, who blended the sounds of subway trains and other urban phenomena. Realistic sound effects were achieved using proprietary SoundLab technologies. During specified periods, visitors will be able to control the localizations of various sounds in the composition via an iPad.