The accompanying figures show the method employed in moving several
buildings of different construction, and the peculiar arrangements that
have been made, according to circumstances.
The instrument most commonly employed in the execution of such work
consists of the following parts: (1) of a cast iron screw having a
pitch of 0.56 inch; (2) of a nut provided with a shoulder and two
projections that serve to fix it; and (3) of a cast iron plate that is
interposed between the head of the screw and the beam upon which the
latter is to exert its pressure. Moreover, each nut is set into an oak
block, 4 inches in thickness, which rests upon the upper beams of the
timber work that is designed to sustain the structure.
All the pieces of wood of the timber work, properly so called, are
of spruce, and measure 6x6 inches. Those that are in a direction
perpendicular to the foundation walls are 3 feet in length while the
longitudinal ones must be long enough to support several screws in
order to annul the effect of joints.
Figs. 1, 2, 3, and 4 represent a house at Buffalo belonging to the New
York and Lackawanna Railroad Company, constructed of bricks and having
a frontage of 90 feet. Between the openings in the latter there are
pillars of dressed stone and cast iron columns. The building is four
stories high, and the outer walls are 1 foot in thickness.
During the month of June, 1882, this structure was raised all in
one piece and moved back 35 feet, in order to give greater width to
the railway. This work was performed in so regular a manner that no
interruption occurred in the business of the Company's offices.
The first operation consisted in running well squared spruce beams, 12
in. × 8 ft., through the walls and under the ground floor. These beams
projected beyond the wall on each side and were spaced about 3¼ feet
apart, and care was taken to have them in the same horizontal plane.
After ramming down the earth upon which the timber work, f, was to
rest, the first transverse beams forming the foundation platform were
laid in place in such a way as to have between them the same spacing
as between the cross-pieces, _a_, and so as to be exactly on the same
level. These were afterward surmounted with longitudinal beams with
alternate transverse ones until the desired height was reached. This
framework having once been put in place, there were placed in the axis
of each piece of timber work string-pieces, _b_, which ran without a
break the entire length of the wall. Jack-screws, _v_, of the kind
above described, were finally arranged in pairs under each of the
cross-pieces, _a_.
On the front side (Fig. 3) particular precautions were taken to support
the stone pillars and iron columns. To this end, apertures were made in
the foundation, starting from the axis of the pillars and terminating
at the axis of the neighboring columns. Spruce sills were put into
these openings and others between the columns, the last-named ones
having been put in place after the masonry had been completely severed.
The cross-pieces, _a_, were thus under the sills, _g_, before the
putting in place of the screws, _v_, and these latter were maneuvered
in such a way as to merely support the structure without lifting any of
its parts.
These preliminaries having been finished, all the pieces of the timber
work were examined with the greatest care, while, at the same time, the
joints were consolidated and the defects in leveling were rectified by
means of spruce wedges.
During the time of lifting, the workmen were arranged in pairs opposite
each other, and on each side of the wall, where each one had 12 to
14 screws to maneuver. In order to render the motion very uniform,
the superintendent of the work gave signals by means of a whistle.
At this moment each man gave the screw a half revolution, passed to
the following one, and continued thus until all the screws under his
supervision had been revolved to the same degree. At a fresh signal
this operation was begun again, and so on.
When the building had been lifted to a height of twelve inches, it
became necessary to raise the screws. To effect this, two rows of beams
(Fig. 7) were added to the timber-work, and each screw was moved in
succession, so as to always leave one in position. By these means the
building was gradually lifted to the desired height, and it now became
necessary to take the requisite measures for moving it back. With
this object in view, spruce floor timbers, _e_, very smooth and well
lubricated with tallow and soap, were laid upon the timber work and
afterward covered with oak planks, _d_, one inch in thickness, and upon
these latter were placed joists, _c_, that supported string-pieces,
_b_, that were firmly fixed to the joists by means of spruce pins
driven in with force. As the floor timbers that were employed had to
be as long as possible, they were united end to end by a strong joint
and prolonged as far as the new spot upon which the edifice was to
rest. Throughout their whole extent they were supported by sleepers
that were fixed firmly in the earth. The entire weight of the structure
being carried by the pieces, _a_, _b_, _c_, _d_, _e_, and _f_, after
the removal of the screws, the jacks, V, were then placed in position,
their heads resting against the string-pieces, _b_, at the points
marked S, and their other extremities being received by a framework
set into the earth. It took but twelve jacks to move the entire mass,
and these were maneuvered under the orders of a superintendent, who
transmitted his signals with a whistle.
It took forty days to perform all these operations, and it required
fifty men to lift the structure. After the jacks, V, had been put in
place, the building was moved in three days, or at the rate of 11.68
feet per day. This is a medium rate of speed to be adopted in the
moving of a structure like this, for, under very favorable conditions,
it might be carried to over eighteen feet per day.
The timber work which was used in lifting the building was afterward
put together again, in the same manner, around prolonged foundations,
and the same were put in place a second time after the manner described
above. After the floor timbers, e, had been removed by slightly lifting
the load, and the structure had been lowered to its proper position,
the intervals between the cross-pieces, _a_, and the walls of the new
foundations were filled in with masonry; the mass was then allowed to
settle gently down into its place and the cross-pieces were removed.
When buildings stand very near each other, timber-work cannot be put
together outside of the walls, and it therefore becomes necessary to
adopt the arrangement shown in Fig. 9, all the work being done here
beneath the structure. The cross-pieces, _a_, occupy here the entire
width of the house, and are spaced about 36 inches apart from axis to
axis. The structure rests upon two pieces of timber work constructed
like the ones mentioned above. Besides this, it is necessary to utilize
the timbers, L, of the flooring, P, for supporting a part of the load.
During the widening of State Street, in Chicago, several three or four
story brick structures were moved in this way. One of these houses was
set back about four feet without the necessity of lifting it. Apertures
(Fig. 10) four feet in length were cut in the foundation walls, the
edges were made level, and planks, _c_ and _c'_, were inserted and
fixed in tightly by wedges. The intervening masonry was removed, and,
after laying planks alongside of those already in place, the structure
was put in motion in the ordinary way.
When single threaded screws are employed for moving buildings, it
requires much time and manual labor to place and move the pieces.
For the purpose of securing greater rapidity in these operations,
Mr. Hollingsworth has devised a sort of jack-screw (Fig. 11) that
consists of a steel screw about eight feet in length and three inches
in diameter, provided with two threads, running in opposite directions.
The nuts are set into the corresponding extremities of two beams, one
of which abuts against a cast iron brace-block, _n_, held in place by
a stirrup-iron, _t_, while the other bears against the string-pieces,
_b_. Thanks to this arrangement, a structure may be moved at one time
over a length of 6 feet instead of 1.3, the latter being the maximum
travel with single screws.
The method in which slide beams, f, are prolonged in view of resisting
the pressure of the jacks is scarcely employed at present, the
objection to it being that it occasions changes of direction from the
line formed by the timber work. For this reason, contractors prefer to
use independent posts to receive the jacks.--_Revue Industrielle_.
[Illustration: FILTER FOR INDUSTRIAL WORKS]
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