MIL-HDBK-1038
rail, the maximum detrimental combination of travel truck float and wheel flange
clearance on the rail head must be included in the analyses.
1) 150 percent of rated capacity on any hook at maximum operating
radius. Rotate positions with the boom in line and perpendicular to the rails
must be considered. The resultant of all forces must be within the rails (track
gauge) or between the main gudgeon pin axes, as applicable.
2) Rated capacity on any hook at maximum operating radius, and 40
mph operating wind from the rear of the upperworks. Rotate positions with the
boom in line and perpendicular to the rails must be considered. The overturning
moment must not exceed 77 percent of the stabilizing moment.
3) No load on the hooks and the boom at its minimum operating
radius. Rotate positions with the boom in line and perpendicular to the rails
must be considered. The resultant of all forces must be within 60 percent of the
distance from the crane's center of rotation to either rail or either main gudgeon
pin axis, as applicable.
4) No load on the hooks, the boom at its minimum operating radius,
and 80 mph non-operating wind from the front of the upperworks. Rotate positions
with the boom in line and perpendicular to the rails must be considered. The
overturning moment must not exceed 80 percent of the stabilizing moment.
If the maximum wind gust velocity at the crane's location is greater than
80 mph, this case must also be applied to the crane in its stowed configuration,
using maximum wind gust velocity.
5.1.3.2
Floating Cranes. The stability requirements defined below apply to
straight-line rated cranes. For variably rated cranes, several hook load/radius
combinations, at 5 to 10 foot increments, are to be used, in the stability cases
defined below. For each case three rotate positions must be considered boom
forward, aft, and over the side. Boom angles are set to correspond to the
required hook radii when the barge is level, before the effect of the actual
maximum list and trim angles is applied.
a)
Roller Path Designs. Except for the inclusion of the list and trim
effects, the same cases as in paragraph 5.1.3.1.a are required for the upperworks.
b)
Rotate Bearing Designs. There are no stability requirements for the
upperworks on rotate bearings, provided that the bearing moment-carrying and
radial capacities are not exceeded.
c)
Entire Crane. For normal operation, the crane (barge) with or
without the maximum deck load, with the upperworks in any position, with any load
(up to rated capacity) on any hook at any radius within its operating range, and
with the water ballast compartments full or empty, the barge must remain within
the limits listed below. (The center of gravity of the deck load is assumed to be
5.0 feet above the level of the cargo laydown area.)
1) Maximum list of 2.5 degrees.
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