d. In wedging up, sufficient pressure should be exerted to relieve the load on the bulkhead, but care should be
taken that flanges of bulkhead stiffeners, deck beams, etc., are not caused to buckle from excessive pressure.
Where necessary, decks may be shored to decks overhead. The shoring should extend to headers on the deck and
under the overhead deck beams so arranged as to distribute the load over a large area or to carry it to some point of
local strength, such as bulkhead overhead. The same procedure should be followed in shoring one bulkhead to another.
In common with other features of damage control, the possible necessity for shoring bulkheads must be recognized,
and general provision for accomplishing this operation must be made beforehand. The actual operation should,
however, be governed by conditions which exist when and if shoring is found necessary.
It should be noted that all effective members, except those used to distribute pressure over wide areas, are direct
compression members. The material at hand, assumed to be wood, should be arranged so that the length of direct
compression members is not more than 30 times the minimum thickness or diameter and preferably not more than 15
times. Thus a 4" x 4" timber could be 10 feet long, but, were it only 5 feet long it could take a 50 percent greater load.
For shoring, which is a temporary emergency expedient, materials may be stressed almost to the breaking point.
Having determined the necessity for shoring, and the type and arrangement, the extent of shoring is largely a question of
trial and error; in other words, add more shores until the bulkhead is held securely.
Although the discussion above refers particularly to shoring bulkheads, it applies also to shoring decks.
Section IV. MATERIALS FOR SHORING
7-4. SHORING MATERIALS. The basic materials required are shores, wedges, sholes, and strongbacks. A shore is a
portable beam. A wedge is a block which is triangular on the sides and rectangular on the butt end. A shole is a flat
block which can be placed under the end of a shore to distribute the pressure. A strongback is a bar or beam of wood or
metal, often shorter than a shore, which is used to distribute pressure or to serve as an anchor for a patch.
7-5. TOOLS AND EOUIPMENT. Many items of tools and equipment are used when shoring. These include wooden
battens, claw hammers, mauls and sledges, handsaws, mattresses and pillows, axes and hatchets, wood clamps,
chainfalls, electric welding machines, oxyacetylene cutting outfits, cold chisels, wood chisels, nails, wooden plugs,
packing sheets, turnbuckles, screw jacks, hydraulic jacks, bolts, nuts, and washers.