ARMY TM 5-5420-212-10-1
MARINE CORPS TM 08676A-10/1-1
(13) Operate jacks to lower bridge onto packing. Remove hood from jacks.
(14) Remove jacks and replace immediately with other two jacks. Reposition jack hoods to head of jacks.
(15) Raise jacks to take weight of bridge off packing. Remove no more than three layers of packing.
(16) Operate jacks to lower bridge onto packing or bank. If lowered onto temporary packing, repeat steps
(14) and (15) to reposition jacks to get bridge onto bank.
(17) Remove all jacks, jack posts, supports, baseplates and loose packing from site.
g.
Jacking When Home Bank has Crossfall
Although there is no need for any site work when the crossfall of the home bank does not exceed a slope of 5% (1
in 20), packing under the baseplates should be used to avoid one jack leaning outwards.
With a crossfall of 10% (1 in 10), one end of the bankseat beam will ground, while the other may still be 1 ft 3 in
(380 mm) above ground. When this happens additional packing will be needed. MGB deck units interleaved with timber
packing (to prevent metal to metal contact), can be used.
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