TM 5-5420-209-12Section III. TECHNICAL PRINCIPLES OF OPERATIONParagraphPage1-13General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10 —1-14Detailed Principles of Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-101-13. General. The Improved Float Bridge (Ribbon Bridge) is a modular bridge with an integral superstructure and float-ing supports. A complete ribbon bridge consists of a ramp bay at each bank and the required number of interior bays tocomplete the bridge between the two ramp bays. The bridge has a roadway width of 13 ft 5 in. (408.9 cm). The bridgeis capable of crossing a class 70 load in currents up to 8 ft/sec (243 cm/sec). Individual bays may be joined to form a raftfor ferrying operations.1-14. Detailed Principles of Operation.a. Transporter.The transporter is either a modified U.S. Army M812 or M945 truck chassis which provides a self-contained unit for transporting, launching, and retrieving the bays, boats, and cradles. A hydraulically operated boommounted at the rear of the transporter works in conjunction with an 11,000 lb (4,994 kg) capacity winch to provide loadingand unloading capabilities. An operator’s control stand located at the left rear of cab contains all hydraulic controls theoperator needs to unload and retrieve bays.b. InteriorBay. Each interior bay is a four ponton folding section consisting of two roadway pontons and two bowpontons. All four pontons are joined together by hinges and pins along adjacent edges. Latches secure the bays in eitherthe open or folded positions. Each roadway ponton is divided into two separate water tight compartments. The roadwaypontons are the main Ioad carrying members of the bridge. The bow pontons provide additional floatation and a personnelwalkway. When the interior bay is unloaded from the transporter into water and all the Iatches securing the bay in the foldedposition have been unlatched, the bay will automatically unfold. When recovering an interior bay Iifting from a single point,either the front or rear hinge pin lifting eye, will close the bay to the folded position and the latches will secure the bay inthe folded position. The interior bay can be loaded onto the transporter either end first.c. RampBay.Each ramp bay is a four ponton folding section consisting of two roadway pontons and two bow pon-tons. All four pontons are joined together by hinges and pins along adjacent edges. Latches secure the bay in either theopen or folded positions. Each roadway ponton is divided into two separate water tight compartments. The roadway pon-tons are the main load carrying members of the bridge. The bow pontons provide additional flotation and a personnelwalkway. The shore end of the ramp bay is tapered and two approach ramps are hinged to the roadway pontons. Twohydraulic pumps and cylinders are mounted in the roadway pontons and permit the entire ramp bay to be raised from 0-20degrees (0-0.349 radians) to accommodate various bank conditions. When the ramp bay is unloaded from the transporterinto water and all the latches securing the bay in the folded position are unlatched, the bay will automatically unfold. Whenrecovering a ramp bay, lifting from a single point, the hinge pin lifting eye will close the bay to the folded position and thelatches will secure the bay in the folded position. The ramp bay must be loaded onto the transporter water end first orelse the bay cannot be loaded onto or properly secured to the transporter.1-10
Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business
