The 140-foot steel-leaved dome serves as the beacon for San Diego’s ten-story, $130 million downtown main library. Endrestudio's conceptual design of the dome explored six different circumferential and segmented options, with the chosen direction utilizing two tiers of post-tensioned, three-dimensional, moon-shaped truss elements. A trio of leaves connect in a hinged arch, with three more stretching over the lower group forming a secondary arch. Adjacent to the dome, the vertical stair tower forms a strong structural core which anchors the two wings of the building with a system of triangulated arms. A special events assembly hall tops this rectilinear cluster with a stunning 30-foot high glass wall that angles out from the building’s exterior. Behind this glass plane, and following its angle, is a single central column with multiple connections. This column holds the cantilever ring to horizontal steel triangular vierendeel trusses as well as two composite precast double tee beams flanked by similar trusses. This structure defines two square roofs separated by a central strip of glass which illuminates the special events hall below.