ing should be at least 3 inches thick and joined directly
Holes for through bolts shall be the same diameter as the
over the joist. The joints should be staggered for greater
bolt itself.
strength and support.
No bolthead should project beyond face of timber on
outside face of fender system.
8-19. Special Tools Needed.
Since you cannot
All piles must be creosoted if they are to be used where
manhandle all of the heavy timbers you will be using to
marine borers are active.
build waterfront structure, special tool are used to move
All lumber must be rough except 4" plank decking, which
and place these timbers. They are known as logger's
shall be finished on wearing side only.
tools and consist of peavys, cant hooks, timber carriers,
and pike poles. The peavy and cant hook are lever type
Basis of design:
tools and are primarily used to roll timbers Timber
Live load--500# per sq. ft.
carriers are considered two-man tools; they are primarily
Pile bearing value--50,000#
used to pick up and/or carry timbers. Pike pole are used
Gantry crane--17-ton capacity.
to hold or steady timbers while they are being placed.
Extreme fiber stresses--wood, 1800# per sq. in.
These tools are shown in figure 47. Although the cane
Compression parallel to grain--wood, 1500# per sq. in.
cannot be considered a special tool, we include it here
Compression perpendicular to grain--wood, 450# per sq.
because it is used to raise and lower heavy timbers, such
in.
as are used in the building of waterfront structures.
Horizontal shear--wood, 15-# per sq. in.
Normally, two men are assigned to the crane: the
Modulus of elasticity--wood, 1,600,00.
operator, and the helper. The helper drives the crane
carrier (truck), hooks and unhooks loads, and signals the
Use O.G. cast iron washers with all bolts.
operator when to lift and lower the load and where to
The length of pile as listed in "Bill of Material"
position the load. Standard signals are used for these
assumes a penetration of 15'. The penetration required
purposes. You will not be called upon to operate the
should be determined by driving tests and the length of
crane; but there will be times when the crane helper is
piles adjusted accordingly.
not available, and at such times you will probably have to
Projecting ends of all bolts should be peened after nuts
help the crane operator with the signals. You will
are tightly drawn.
probably be working with the standard crane signals,
illustrated in figure 48. Study and learn the signals
8-22. Let's take a look at some of the problems of
thoroughly, because f you give the crane operator an
general maintenance of waterfront structures with which
incorrect signal, it could cause an accident that would
those, like you, in the specialized carpentry field should
damage some very expensive equipment. Remember,
be familiar. To begin with, what are the primary causes
after the heavy timbers have been moved and placed,
of pier or wharf construction failures?
they must be leveled properly. The carpenter's level,
which you learned about in Memorandum 531, is the tool
8-23. General Maintenance Problems. Chief among
used for this purpose.
the general maintenance problems resulting from pier or
8-20. Let's assume that you are going to remove and
wharf construction failure are the same causative factors
replace some damaged wooden pier component. Before
as those that damage warehouse loading docks. To these
you can replace the component, you must prepare them
can be added storms, collisions, and marine borers.
by boring boltholes, notching for special fits, etc. Also,
8-24. Deterioration is also responsible for some pier
you must know and use certain types of timbers,
and wharf failures. This deterioration may be anticipated
equipment and specifications. What are some of these
and corrected as outlined below. It is caused by decay
things you should know?
and the action of termites and marine borers. Decay,
8-21. These items of information are called General
turn, caused by the action of low parasitic forms of plant
Notes and are found on the construction plan. They
life known as fungi. The growth of these fungi depend
should be used any time you construct a new structure or
upon moisture, food, air, and temperature (warmth).
repair an existing one.
Consequently, the absence of any one of these
From these notes you will get such information as the
requirements will prevent fungi growth. However, the
size hole to drill for driftpins and bolts, how bolts should
most general and successful way to stop fungi growth is
be placed, basis of design, type of hardware to use, etc
to poison the food supply We usually poison the food
Let's take a look at a sample General Notes legend.
supply by treating the timber itself with creosote.
8-25. Termite attacks on structural building timbers
General Notes
are probably the chief causes of insect damage. This is
specifically true of timber components which are in direct
Holes for driftpins (D.P.) shall be 1/16" smaller than the
contact with the earth. Although termite are the chief
pin itself.
causes of damage, they are not the only damaging insects.
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