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1858-'9.] Document Ko. 19. 10
Hancock street, in the toM^ of New-Berne. It is 1836 feet
in length, inchidingthe abutments—with an embankment pro-tected
by a Rip Rap wall from the west abutment to the shore
line of 447 feet, and from the east abutment to the shore line
of 127 feet. It rests upon two abutments and 12 piers, inclu-ding
the pivot octagonal pier for the Draw. The spans are
156 feet from centre to centre of ])ier, and 120 feet in length
of Draw, affording 50 feet openings for the passage of vessels.
In establishing the foundations of this important structure, it
was ascertained by accurate borings that the water varied in
depth from 7 to 18 feet in the channel, that after a layer of
mud and sand, varying from 12 to 22 feet in depth, the rod
]"eached a conglomerate shell rock, common to this region of
North-Carolina, and extending entirely across the river. This
rock is composed of shells of different sizes, united and bound
together b}' a strong cement. Upon this rock the piers and
abutments have been founded in the following manner: Con-sidering
the depth of material above the rock as ample to hold
in position a system of piles, I adopted the plan of driving
piles over the whole space to be occupied by each pier and
abutment down to the rock, penetrating it slightly ; these piles
were then sawed off to an exact plane 10 to 12 inches above
the alluvial deposit at the bottom of the river, by means of a
saw attached to a proper framing, and let down from the steam
Pile-driver, by which it was worked, and the piles sawed off'
with great rapidity and accuracy, their number being 950. A
grillage was then formed of a size to project 2 feet beyond the
masonry, of three thicknesses of 12 X 12 in timber, fitting
close and well bound together by 2 inch treenails, every 6th
timber of the bottom course of this grillage jM-qJected 18 inches.
It was then floated over the piles which had been sawed off.
and secured in its position by guide piles driven on the out
side and in contact with the projecting bottom timbers. These
guide piles were then sawed off 2 feet above the surface of the
water of the river, and capped with a 12 X 12 inch sill. Into
this sill there were female screws fitted to receive screw rods,
which took hold of the projecting timbers, and were long
enough to lower the grillage dowm upon tlie piles. A timber
Object Description
Description
| Title | Page 919 |
| Full Text | 1858-'9.] Document Ko. 19. 10 Hancock street, in the toM^ of New-Berne. It is 1836 feet in length, inchidingthe abutments—with an embankment pro-tected by a Rip Rap wall from the west abutment to the shore line of 447 feet, and from the east abutment to the shore line of 127 feet. It rests upon two abutments and 12 piers, inclu-ding the pivot octagonal pier for the Draw. The spans are 156 feet from centre to centre of ])ier, and 120 feet in length of Draw, affording 50 feet openings for the passage of vessels. In establishing the foundations of this important structure, it was ascertained by accurate borings that the water varied in depth from 7 to 18 feet in the channel, that after a layer of mud and sand, varying from 12 to 22 feet in depth, the rod ]"eached a conglomerate shell rock, common to this region of North-Carolina, and extending entirely across the river. This rock is composed of shells of different sizes, united and bound together b}' a strong cement. Upon this rock the piers and abutments have been founded in the following manner: Con-sidering the depth of material above the rock as ample to hold in position a system of piles, I adopted the plan of driving piles over the whole space to be occupied by each pier and abutment down to the rock, penetrating it slightly ; these piles were then sawed off to an exact plane 10 to 12 inches above the alluvial deposit at the bottom of the river, by means of a saw attached to a proper framing, and let down from the steam Pile-driver, by which it was worked, and the piles sawed off' with great rapidity and accuracy, their number being 950. A grillage was then formed of a size to project 2 feet beyond the masonry, of three thicknesses of 12 X 12 in timber, fitting close and well bound together by 2 inch treenails, every 6th timber of the bottom course of this grillage jM-qJected 18 inches. It was then floated over the piles which had been sawed off. and secured in its position by guide piles driven on the out side and in contact with the projecting bottom timbers. These guide piles were then sawed off 2 feet above the surface of the water of the river, and capped with a 12 X 12 inch sill. Into this sill there were female screws fitted to receive screw rods, which took hold of the projecting timbers, and were long enough to lower the grillage dowm upon tlie piles. A timber |
