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Bridge engineering is dominated by bespoke design, where new solutions are sought for each site. Despite potential cost and time savings, modular technologies are rarely pursued. To serve as inspiration for innovation in modular technologies, this paper presents a historical case study of the Système Eiffel – a modular, steel bridge system based on repeated triangular modules or elements used throughout the world. While Gustave Eiffel was widely known for his great iron bridge designs in Europe, his contributions to modular and rapidly erectable bridges are less known. This paper presents his system, including 1) the reasoning behind the design as described in documents by Eiffel, 2) a description of the structural system of one bridge type, including detailed plans and the erection strategy (i.e. launching), and 3) a catalog of the other bridge types that included minor variations. While this paper is historical in nature, it highlights an innovative, modular approach to bridge design that was appropriate at a particular moment in history and aims to spark innovation in bridge engineering today.
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Modular Lattice Bridges Inspired by Système Eiffel
This paper presents the development and numerical investigation of a novel form for resilient lattice bridges inspired by the Système Eiffel. While Gustave Eiffel is known for his major works of structural art (e.g., Maria Pia Bridge), he was also a pioneer in modular and rapidly erectable bridges that were used worldwide. His Système Eiffel consists of triangular modules, with each module being made up of angle sections. These are joined to one another in an alternating fashion, with adjacent modules rotated 180 degrees. The same module could achieve a variety of spans (6-21 m), and deeper versions were used for longer spans (up to 30.8 m). Inspired by Eiffel, but factoring in today’s economic and labor market, this research has developed a novel approach to modular lattice bridges. Specifically, this research harnesses Eiffel’s approach of rotating adjacent modules, but instead focuses on the connector as the module that joins standard sections. Importantly, the lattice-type layout provides the structure with system redundancy, meaning that the fracture of one member does not cause collapse. This paper presents the numerical investigation of these modular lattice bridges through finite element analyses, considering behavior under dead and live load, global stability, and performance when subjected to member loss.
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- Award ID(s):
- 2044340
- PAR ID:
- 10571335
- Publisher / Repository:
- International Association for Shells and Spatial Structures
- Date Published:
- Subject(s) / Keyword(s):
- Lattice, bridge, modular design, rapid construction, redundancy, resiliency
- Format(s):
- Medium: X
- Location:
- Zurich, Switzerland
- Sponsoring Org:
- National Science Foundation
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