Along with its visors, a deerstalker has a pair of unstiffened cloth earflaps attached to either side of the cap. These are tied together by grosgrain ribbons or by laces or, very occasionally, held together by snaps or a button. The earflaps, tied under the chin, provide protection in cold weather and high winds. They are otherwise tied together above the crown to keep them out of the way.
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The effects of this loading condition can trigger different types of failure mechanisms. For the case of unstiffened shell structures, the bulging factor can be defined as the ratio of stress-intensity (SIF) of a curved shell to the stress-intensity factor of a flat panel: bulging factor = SIF(curved)/SIF(flat) The representation of this phenomenon becomes rather complex due to the biaxial and internal pressure load and structural configuration.
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Erection Sequence and Force Diagram for the bridges, produced by the Historic American Engineering Record in the 1990s. The full diagram includes the following text: A suspension bridge works by hanging a roadway from cables or chains under tension. Though a few unstiffened suspension bridges exist, a longitudinal stiffening truss or girder is usually added to prevent excessive movement of the deck. The cables pass over towers and are anchored at both ends. Conventional suspension bridges use massive concrete or rock anchorages to resist the cable’s tension.
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The whole structure cost £2,300 and weighed only 113 tonnes--less than the loads it was expected to carry. ;Construction Work was started on the bridge in 1829 and it was opened on 27 December 1830. ;Trials and operation When the first trial steam engine and train of loaded coal wagons crossed the bridge on 27 December 1830, the bridge flexed so much that the unstiffened bridge deck rose like a static wave in front of the engine. One particular trial load was enough to damage the towers with one tower on the Yorkshire side cracking.
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Brown went on to build several further chain bridges, as well as the Trinity Chain Pier in Newhaven, Edinburgh (opened in 1821 and destroyed in a storm in 1898) and the Chain Pier at Brighton (1823–1896).Chain Pier Encyclopaedia of Brighton by Tim Carder, 1990, Brighton & Hove Most of his designs used an unstiffened bridge deck, before it became clear that this form was vulnerable to wind forces and unstable under concentrated loads. His designs were reviewed by eminent engineers including John Rennie and Thomas Telford, and generally approved. Brown's designs were significantly less conservative than his contemporaries, adopting a higher tensile strength for his iron chains.
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The 1830 bridge was an iron chain suspension bridge built principally to carry coal on the Stockton and Darlington Railway to Port Darlington, later to be renamed Middlesbrough, and was to be the first suspension bridge built for railway traffic. Drawings of the original 1830 Stockton Railway Bridge ;Design The designer was Sir Samuel Brown, a retired naval officer with experience building the 1820 Union Bridge over the River Tweed between Scotland and England, and the Royal Suspension Chain Pier, Brighton (1823). Stockton Railway Bridge was long with a main span of . The wide unstiffened bridge deck was suspended using of round eye bar link chain supported by two masonry towers, giving of clearance (heading) on the river below the deck and there were lattice timber parapets on either side of the deck.
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In addition to its distinctive patch, worn opposite of the regular Philadelphia P.D. patch (district patrol officers wear the regular patch on the left sleeve, with no patch on the right sleeve), the members of the Highway Patrol also wear the so-called "50-Mission" unstiffened cap, instead of the 8-point stiff NYPD- style cap, the full Sam Browne Belt without cross strap, (cross strap added only on the Leather Coat and Blouse coat), and knee-high black "cavalry" boots and breeches instead of regular trousers and shoes. They also wear a double- breasted black leather coat instead of the regular nylon patrol jacket. This uniform style dates back to the 1920s when the Highway Patrol officers rode around on motorcycles for all patrols. Because of the mixed use of patrol cars and motorcycles today, the only "non-interchangeable" item is the cap, which is replaced with a safety helmet mandated for all motorcycle officers..
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