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Theoretically optimal forms for very long-span bridges under gravity loading.

ABSTRACT: Long-span bridges have traditionally employed suspension or cable-stayed forms, comprising vertical pylons and networks of cables supporting a bridge deck. However, the optimality of such forms over very long spans appears never to have been rigorously assessed, and the theoretically optimal form for a given span carrying gravity loading has remained unknown. To address this we here describe a new numerical layout optimization procedure capable of intrinsically modelling the self-weight of the constituent structural elements, and use this to identify the form requiring the minimum volume of material for a given span. The bridge forms identified are complex and differ markedly to traditional suspension and cable-stayed bridge forms. Simplified variants incorporating split pylons are also presented. Although these would still be challenging to construct in practice, a benefit is that they are capable of spanning much greater distances for a given volume of material than traditional suspension and cable-stayed forms employing vertical pylons, particularly when very long spans (e.g. over 2?km) are involved.

SUBMITTER: Fairclough HE

PROVIDER: S-EPMC6189590 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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Theoretically optimal forms for very long-span bridges under gravity loading.

Fairclough Helen E HE Gilbert Matthew M Pichugin Aleksey V AV Tyas Andy A Firth Ian I

Proceedings. Mathematical, physical, and engineering sciences 20180919 2217

Long-span bridges have traditionally employed suspension or cable-stayed forms, comprising vertical pylons and networks of cables supporting a bridge deck. However, the optimality of such forms over very long spans appears never to have been rigorously assessed, and the theoretically optimal form for a given span carrying gravity loading has remained unknown. To address this we here describe a new numerical layout optimization procedure capable of intrinsically modelling the self-weight of the c ...[more]

PMID: 30333690

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Dataset Information

Theoretically optimal forms for very long-span bridges under gravity loading.

Publications

Theoretically optimal forms for very long-span bridges under gravity loading.

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