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
8-19. Special Tools Needed.
Since you cannot
outside face of fender system.
manhandle all of the heavy timbers you will be using to
All piles must be creosoted if they are to be used where
build waterfront structure, special tool are used to move
marine borers are active.
and place these timbers. They are known as logger's tools
All lumber must be rough except 4" plank decking, which
and consist of peavys, cant hooks, timber carriers, and
shall be finished on wearing side only.
pike poles. The peavy and cant hook are lever type tools
and are primarily used to roll timbers Timber carriers are
Basis of design:
considered two-man tools; they are primarily used to pick
Live load--500# per sq. ft.
up and/or carry timbers. Pike pole are used to hold or
Pile bearing value--50,000#
steady timbers while they are being placed. These tools
Gantry crane--17-ton capacity.
are shown in figure 47. Although the cane cannot be
Extreme fiber stresses--wood, 1800# per sq. in.
considered a special tool, we include it here because it is
Compression parallel to grain--wood, 1500# per sq. in.
used to raise and lower heavy timbers, such as are used in
Compression perpendicular to grain--wood, 450# per
the building of waterfront structures. Normally, two men
sq. in.
are assigned to the crane: the operator, and the helper.
Horizontal shear--wood, 15-# per sq. in.
The helper drives the crane carrier (truck), hooks and
Modulus of elasticity--wood, 1,600,00.
unhooks loads, and signals the operator when to lift and
lower the load and where to position the load. Standard
Use O.G. cast iron washers with all bolts.
signals are used for these purposes. You will not be
The length of pile as listed in "Bill of Material"
called upon to operate the crane; but there will be times
assumes a penetration of 15'. The penetration required
when the crane helper is not available, and at such times
should be determined by driving tests and the length of
you will probably have to help the crane operator with the
piles adjusted accordingly.
signals. You will probably be working with the standard
Projecting ends of all bolts should be peened after nuts
crane signals, illustrated in figure 48. Study and learn the
are tightly drawn.
signals thoroughly, because f you give the crane operator
an incorrect signal, it could cause an accident that would
8-22. Let's take a look at some of the problems of
damage some very expensive equipment. Remember,
general maintenance of waterfront structures with which
after the heavy timbers have been moved and placed, they
those, like you, in the specialized carpentry field should
must be leveled properly. The carpenter's level, which
be familiar. To begin with, what are the primary causes
you learned about in Memorandum 531, is the tool used
of pier or wharf construction failures?
for this purpose.
8-23. General Maintenance Problems. Chief among
8-20. Let's assume that you are going to remove and
the general maintenance problems resulting from pier or
replace some damaged wooden pier component. Before
wharf construction failure are the same causative factors
you can replace the component, you must prepare them by
as those that damage warehouse loading docks. To these
boring boltholes, notching for special fits, etc. Also, you
can be added storms, collisions, and marine borers.
must know and use certain types of timbers, equipment
8-24. Deterioration is also responsible for some pier
and specifications. What are some of these things you
and wharf failures. This deterioration may be anticipated
should know?
and corrected as outlined below. It is caused by decay
8-21. These items of information are called General
and the action of termites and marine borers. Decay, turn,
Notes and are found on the construction plan. They
caused by the action of low parasitic forms of plant life
should be used any time you construct a new structure or
known as fungi. The growth of these fungi depend upon
repair an existing one.
moisture, food, air, and temperature (warmth).
From these notes you will get such information as the size
Consequently, the absence of any one of these
hole to drill for driftpins and bolts, how bolts should be
requirements will prevent fungi growth. However, the
placed, basis of design, type of hardware to use, etc Let's
most general and successful way to stop fungi growth is
take a look at a sample General Notes legend.
to poison the food supply We usually poison the food
supply by treating the timber itself with creosote.
General Notes
8-25. Termite attacks on structural building timbers are
probably the chief causes of insect damage. This is
Holes for driftpins (D.P.) shall be 1/16" smaller than the
specifically true of timber components which are in direct
pin itself.
contact with the earth. Although termite are the chief
causes of damage, they are not the only damaging insects.
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