ARMY TM 5-5420-212-23
MARINE CORPS TM 08676A-23/2
Section III. PRINCIPLES OF OPERATION
1-11 INTERFACE OF MGB COMPONENTS
This section describes how the major MGB components work and interface with each other. The use of individual
components varies, depending on the type and length of bridge being assembled.
FIGURE 1-4 Launching Single Story Bridges up to 50ft (15.2m)
TOP PANEL. Forms the main girders of the bridge. Top panels are connected to each other and other panels by
shootbolts and panel pins, using a guide system to align the panels to enable the panel pins to be inserted.
BANKSEAT BEAM. Provides the spacing between bridge girders and can support MGB's maximum load when
bearing along its length. Bankseat beam connects to top panels or end taper panels.
LIGHT LAUNCHING NOSE, FRONT AND REAR. Used as a complete launching nose for 4 thru 8 bay single story
bridges and as the forward section of the launching nose on all other bridges. They connect to each other using a
launching nose pin. The rear light launching nose connects to the bankseat beam or the launching nose heavy.
ROLLER BEAM ON FIXED SUPPORT AND BASEPLATE. Allows the bridge to be boomed (moved) during
assembly or disassembly, using rollers which can be locked. Ground conditions determine whether the roller beam
is placed on fixed supports and baseplates during launch of single story bridges.
LANDING ROLLER. Used on far bank to receive the launching nose. Can be used on ground for 4 thru 8 bay
single story, or on landing roller pedestal for longer bridges.
BUILDING PEDESTAL. Used under girders to keep bridge off ground during construction of all single story