Truss Bridges
Balls Bridge and Truss Bridges: A Brief Historical Overview
Nathan Holth
Foreword: I composed this brief and informal overview of truss bridges and Balls Bridge to put this beautiful historic bridge 's history and significance into context. A version of this document with full-color photos is available on my website 's Balls Bridge Page located at www.historicbridges.org/ontario/balls/index.htm which also has more information and photos. The general truss bridge information in this document was adapted from a formal research paper I composed. This paper, which cites the many different sources I used to produce the history of truss bridges, is available at www.historicbridges.org/info/intro/trusshistory_c.pdf in PDF format. The metal truss bridge features a network of metal beams arranged in a pattern based on triangles that work to support the bridge. The metal truss bridge was essentially the result of the transition from wood to metal for use in bridge building. Although experiments in metal bridges had been going on for many years, it was not until the 1870s that metal bridges began to take off and began to be the preferred material over wood. During the 1870s, the bowstring truss became the preferred metal bridge structure type. By the early 1880s however, the bowstring truss bridge fell out of favor to the stronger and more easily designed pin-connected Pratt truss bridge. Pin connections allowed for easy assembly of the truss parts at the construction site, and required little skill to erect. From roughly 1880 through 1910, the pinconnected truss bridge was the most common bridge type built. The numerous bridge companies around at the time designed truss bridges to market to townships and municipalities. These companies, mostly free to design their bridges as they wished, would often develop their own style of truss bridge, which resulted in a wide variety of appearances from bridge to bridge. Some were simple, and relatively plain, while others were
Nathan Holth
Foreword: I composed this brief and informal overview of truss bridges and Balls Bridge to put this beautiful historic bridge 's history and significance into context. A version of this document with full-color photos is available on my website 's Balls Bridge Page located at www.historicbridges.org/ontario/balls/index.htm which also has more information and photos. The general truss bridge information in this document was adapted from a formal research paper I composed. This paper, which cites the many different sources I used to produce the history of truss bridges, is available at www.historicbridges.org/info/intro/trusshistory_c.pdf in PDF format. The metal truss bridge features a network of metal beams arranged in a pattern based on triangles that work to support the bridge. The metal truss bridge was essentially the result of the transition from wood to metal for use in bridge building. Although experiments in metal bridges had been going on for many years, it was not until the 1870s that metal bridges began to take off and began to be the preferred material over wood. During the 1870s, the bowstring truss became the preferred metal bridge structure type. By the early 1880s however, the bowstring truss bridge fell out of favor to the stronger and more easily designed pin-connected Pratt truss bridge. Pin connections allowed for easy assembly of the truss parts at the construction site, and required little skill to erect. From roughly 1880 through 1910, the pinconnected truss bridge was the most common bridge type built. The numerous bridge companies around at the time designed truss bridges to market to townships and municipalities. These companies, mostly free to design their bridges as they wished, would often develop their own style of truss bridge, which resulted in a wide variety of appearances from bridge to bridge. Some were simple, and relatively plain, while others were