Evening star. [volume] (Washington, D.C.) 1854-1972, 1903-03-13
TROUBLE OVERCOME
MAI. SEWELL'S PLAN FOR WAR
COLLEGE FOUNDATION.
Concrete Piles Substituted for Wooden
Ones, Which Had Been Found
to Be Unsuitable.

Major Sewell, the engineer officer in
charge Of the extensive improvements at
Washington barracks, has finally sur
mounted the physical difficulties encoun-
tered in preparing the foundations for the
War College, officers quarters and other
buildings which were due to the alternate
wet and dry conditions of the earth due to
heavy and frequent rains. Wooden piles
having been found unsuitable for the work,
a system of concrete piles was adopted,
and Maj. Sewell reports that the system,
having been further developed, seems to be
entirely successful.
In a report to the War Department he
has given description of the work as now
conducted, which will be. of considerable
interest to all persons concerned in the
laying Of concrete pile foundations. con-
crete mold. shaped something like pro-
jectile, with tenon on its upper end is
used for the driving point. The maximum
diameter of the concrete point varies from
fourteen to sixteen inches The tenon is
of such diameter that it fits fairly close
inside an extra heavy ten-inch steam pipe
The approximate length of pile having
been determined, sheet iron casing a lit
tie less in diameter than the thickest part
of the concrete point, is made so as to be
a little longer than the required pile The
point is set up between the guides of the
pile driver at the place where the pile is
to be driven. The sheet iron casing is then
SET vi eop " tHe point ana the steam pipe
lowered inside the casing and adjusted
over the tenon on the point. Flanges on
the steam pipe and casing, give necessary
bearing area for the driving The steam
pipe has large driving head made of
wood combined with iron.
Driven to Firm Stratum.
The pile having been built up in this
way is driven until it appears to have reach
ed sufficiently firm stratum The steam
pipe Is then Withdrawn. 1t is found that
the shock Of driving always breaks the
tenor off at the point where 1t Joins the
thick part of the concrete point 1t is
made with projecting loop at the top
by means of a light steel rod built in with
the concrete. By means of this loop the
tenon is fished out after the steam pine
is withdrawn. The pile driver then goes
ahead and drives piles. There are several
sheet-iron castings for each size of bile,
AS soon as the pile driver has moved off
two or three piles the process of filling
them with concrete begins. A little con-
crete Is thrown into the easing and ram
med The casing is then withdrawn lit
tie, not far enough, however, to clear the
concrete; then more concrete is put in and
rammed, and this operation is repeated
as often as is necessary. THE casing is
easily withdrawn By means of a simple
winch worked by hand. Vi
Inc net result is a concrete column of
full size and practically uniform section
throughout. resting on bed of firm sand
below the fill. The diameter is SO nro-
portioned that it shall never be-fess-t than
10 per cent of the length of the pile Major
seWeii says that tests made on these piles
indicate that they will be abundantly able
to carry their loads. With the exception of
putting these piles for the founda tons of
the various buildings, no work was posi-
BILE on the reservation last month, on ac-
count OF the extremely wet condition Of the
ground