Transactions of the American Society of Civil Engineers, vol. LXVIII, Sept. 1910 | Page 9

appear in the contract: Excavation
of rock in trenches, 3,400 cu. yd.; excavation of rock in pit, 377,000 cu.
yd.; excavation of all materials except rock in trenches, 6,500 cu. yd.;
excavation of all materials except rock in pit, 34,000 cu. yd.; concrete,
1:3:6, in retaining walls, 4,580 cu. yd.; concrete, 1:3:6, in face walls,
7,460 cu. yd.; concrete, 1:2:3, with 3/4-in. stone, in face walls, 4,100 cu.
yd.; stone masonry in portal, 247 cu. yd., etc., etc.
[Illustration: Fig. 7. (Full page image)
NINTH AVE. ABUTMENTS & KEY PLAN]
As previously stated, the contract price included the placing of all
excavated material on scows at Pier 62, North River. Prior to this
contract this pier had been used by the New York Contracting
Company-Pennsylvania Terminal, for the disposal of excavated
material from east of Ninth Avenue. In order to get the material to the
pier, the contractor had excavated a cut under Ninth Avenue which
came to the grade of 32d Street about midway between Ninth and
Tenth Avenues, and a trestle was constructed from this point over
Tenth Avenue and thence to the pier. Fig. 2, Plate XLVII, shows the
east end of this cut, and Fig. 1, Plate L, shows the trestle, looking east
from Tenth Avenue.
A 30-ton steam shovel was brought to the south side of the work, and
commenced operating on July 9th, 1906. After working there about a
month, the earth had been practically stripped off the rock, and the
shovel was moved over to the north side where it excavated both earth
and rock until August 10th, 1907.
At three points south of 32d Street and at one point north of 32d Street

near Tenth Avenue, cuts were made in the rock to sub-grade, and from
these cuts, together with the cuts on the west side of Ninth Avenue, all
widening out was done and the excavation was completed. Fig. 1, Plate
L, shows the excavation of the three cuts on the south side of 32d Street,
the steam shovel operating on the north side of that street, and the
material-disposal tracks and trestle. Fig. 3, Plate LII, shows the cuts
joined up and the excavation along the south side practically
completed.
On the north side of the work, between Stations 182 + 90 and 183 + 65,
the rock was low, and provision had to be made for maintaining the
yards to the north of the site. Therefore a rubble-masonry retaining wall
was built, with the face about 2 ft. north of the face of the proposed
concrete wall which was to be put in later. On the same side of the
work, between Stations 188 + 24 and 188 + 46, the rock was
exceedingly poor, and as a small frame house on the adjoining lot was
considered to be in an unsafe condition, a rubble masonry retaining
wall was built. As the building adjoining the south side of the work at
Tenth Avenue was on an earth foundation, it was necessary to underpin
it before the excavation could be done. The building was supported on
needles, and rubble masonry was put in from the bottom of the old
foundation to the rock. The foundation of 413 West 31st Street,
immediately west of the Express Building site, was of very poor
masonry, and it was necessary to rebuild it prior to taking out the
adjoining excavation.
[Illustration: PLATE L, FIG. 1.--TW 23, P.N.Y. & L.I.R.R. Terminal
Station West. View looking Eastward from Tenth Ave., showing work
between Ninth & Tenth Avenues. Dec. 26, 06.]
[Illustration: PLATE L, FIG. 2.--TW 35, P.T. & T.R.R. Co. Terminal
Station West. View looking Northwest from Sta. 184, 120 feet South of
center line. Dec. 31, 07.]
[Illustration: PLATE L, FIG. 3.--TW 96, P.T. & T.R.R. Co. N.R. Div.
Terminal Station West. View looking West from Ninth Avenue
Elevated Railway, showing condition of work. May 26, 09.]

[Illustration: PLATE L, FIG. 4.--TW 104, P.N.Y. & L.I.R.R. Terminal
Station West. View from Tenth Avenue looking East, showing progress
of concrete walls. Aug. 7, 09.]
Along the north side, between Stations 186 + 50 and 187 + 50, the
walls supporting the adjoining back yards were of poor quality and had
to be renewed by the contractor before excavation could be done.
The excavated material was loaded by derricks on cars at the top of the
excavation, these cars being on tracks having a direct connection with
the disposal trestle, as shown by Fig. 1, Plate L. As soon as it could be
done, derricks were placed at the bottom of the excavation; tracks were
then laid out there, and the excavated material was loaded on cars at the
bottom and hoisted by derricks to cars on the disposal trestle. A
locomotive was lowered to the bottom of the