ARMY TM 5-5420-212-10-1
MARINE CORPS TM 08676A-10/1-1
3-4 PRELIMINARY STUDIES
A thorough evaluation of information from preliminary studies may aid the reconnaissance by limiting it to a few suit-
able sites. Sources of preliminary information are intelligence studies and reports, interviews with local civilians, maps,
aerial photographs, and personal aerial reconnaissance.
3-5 SITE SELECTION
Whenever possible, aground reconnaissance is made to find a site that has selection factors desirable for construc-
tion of single story and double story MGBs, with and without reinforcement. Following are the factors that must be con-
sidered during the reconnaissance.
a. Access Routes
Access routes at each end of the bridge that tie in to the main road network. These routes should not require too much
maintenance or preparation.
b. Approaches
(1) Single and Double Story MGB
Approaches requiring little preparation. Should be two lanes wide and straight for 160 ft (48.8 m) at each end of the
bridge. Slope of the approach should not exceed 1 in 10. Transverse (side to side) slope should not exceed 1 in 10 (up
to 5 bay SS) or 1 in 20 (all other bridges) in the first 60 ft (18.3 m) measured from the A’ peg. See Figures 3-1, 3-2 and
Chapter 1, Table 1-1.
(2) Link Reinforced MGB
Approaches requiring little preparation. Should be two lanes wide and straight for 160 ft (48.8 m) at each end of the
bridge. Slope of the approach should not exceed 1 in 20. Transverse (side to side) slope should not exceed 1 in 20 in
the first 60 ft (18.3 m) measured from the A’ peg. See Figure 3-2.
3-8
Change 2
