BRIDGE SPAN Russian patent published in 2011 - IPC E01D4/00 

FIELD: construction.

SUBSTANCE: bridge span of open arched type with riding at the bottom includes main arched trusses (1) joined with laminate transverse semi-frames (2). Main arched trusses are made with lens-shaped contour and flexible tightening and are formed by upper belt in the form of bent laminate arch (3) and lower flexible steel belt (4), joined to each other by means of stands (5) of transverse semi-frames of alternating height. Beams of trafficway are supported by crossbars of semi-frames, and trafficway is equipped with longitudinal and transverse joint units. Under crossbars there are supporting flexible spring-loaded guy ropes fixed by their ends in fixed and movable supports of bridge. The novelty is the fact that guy ropes may be fixed in bridge supports or with the help of transverse beam elements that transfer guy rope forces to support units of main trusses, or directly in bridge abutments. In the last case movable support is equipped with a fixture with spring device providing for pre-stressed condition of guy rope. Besides, in bridge span there are devices installed for prestressing of guy ropes, lower belts of main trusses are arranged as collapsible, and semi-frames are suspended to bent laminate arches with the help of collapsible units.

EFFECT: improved efficiency of design and higher operational properties by provision of optimal operation of all elements in design.

6 cl, 12 dwg