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Title: All glass, compression-dominant polyhedral bridge prototype: form-finding and fabrication
The recent development of three-dimensional graphic statics using polyhedral reciprocal diagrams (PGS) has greatly increased the ease of designing complex yet efficient spatial funicular structural forms, where the inherent planarity of the polyhedral geometries can be harnessed for efficient construction processes. Our previous research has shown the feasibility of leveraging this planarity in materializing a 10m-span, double-layer glass bridge made of 1cm glass sheets. This paper presents a smaller bridge prototype with a span of 2.5m to address the larger bridge’s challenges regarding form-finding, detail developments, fabrication constraints, and assembly logic. The compression-only prototype is designed for prefabrication as a modular system using PolyFrame for Rhinoceros. Thirteen polyhedral cells of the funicular bridge are materialized in the form of hollow glass units (HGUs) and can be prefabricated and assembled on-site. Each HGU consists of two deck plates and multiple side plates held together using 3M™ Very High Bond (VHB) tape. A male-female glass connection mechanism is developed at the sides of HGUs to interlock each unit with its adjacent cells to prevent sliding. A transparent interface material is placed between the male and female connecting parts to avoid local stress concentration. This novel construction method significantly simplifies the bridge’s assembly on a more » large scale. The design and construction of this small-scale prototype set the foundation for the future development of the full-scale structure. « less
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Journal Name:
Proceedings of the International Association of Shell and Spatial Structures
Sponsoring Org:
National Science Foundation
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