As part of a government masterplan seeking to spur the development of Jiangdon, a new district in Haikou City, Penda China has completed three portals providing access to a new tunnel. Built beneath the Nandu River, the tunnel spans 4,280 meters (14,370 feet) in length and 2, 720 meters (8,924 feet) in width. The tunnel connects Haikou City with Changmai County and Wenchang City as part of the overall economic integration of the area.
The sculptural portals are inspired by marine life forms, in particular white clamshells. Clad with glazed white aluminium panels, contrasting black lines follow the curving forms. The undersides of the canopies are likewise clad with the same white panelling.
There are three access points to the new tunnel, one of them larger in scale and on the east side of the shoreline. The other two are on the west side and smaller in scale. Typically, vehicular tunnel entrances must provide a transition zone to allow the human eye time to acclimate to the change in brightness when entering a tunnel. Here, instead of relying on the conventionally used LED light grilles, a curving madeleine-shaped canopy with an open clamshell shape brings in natural light, while maintaining uniformity of luminance at the tunnel entrance
Marine bioluminescence was also an influence on the design. Multiple small lights are embedded between the lines of the cladding panels of all three portals so that at night the shells appear to glow.
‘From a bird’s eye point of view, these futuristic landmark entrances stand out from the existing city fabric and provide a tinge of surrealism to Haikou’ say the architects.
