The sun. [volume] (New York [N.Y.]) 1833-1916, 1915-12-05
Continued from First Page.

'OVtInuen from FWSt fn0s.
Il be necessary to increase the height
Of the embankment after troubles OF
this kind have started they are cured
by extending the base OF the super
imposed mass sufficiently to establish
equilibrium: the extent to which this
blanket should be carried is deter
mined experimentally.
soft Earth Forced Up.
II instead Of building up an em-
oankment on ground so constituted a
trench be cut through 1t the removal
Of the material from the cutting will
change the distribution of the o OF
the adjacent banks. and IL the exca-
walton be carried deep enough results
will DO produced similar to those in
the foregoing case Of the embankment.
!. e., either the soft or underlying
strata will be forced into h C.
vaied area or the bottom of the latter
will be pushed up. when rupture is
caused before the bottom OF the ex-
oavation reaches the weaker layer.
In either case the bank above the
broken strata is ruptured and there
will he "A movement Of a portion Of
the bank into the trench, the motion
continuing until equilibrium Is reached.
The trench Is filled or partly filed
by the material that moves in. and
when this is taken out additional ma
terial may break away. and SO the
operation continues until final eQuilib-
rum and ultimate STABILITY are
unless, as in the case OF the
ments some means can he adopted to
reduce the loa OF the adjacent
other than allowing all the material
to enter the prism for removal. The
results which follow in the foregoing
cases are modified through
causes. such as alternate freezing and
thawins and excessive moisture u
to rains or snow.
The foregoing or various
materials under varying conditions ex-
plains he causes OF the slides that
nave been oncountered IN n con-
Struction OF the canal. They occurred
at points all along the line from the
lower end or Gatun locks TO The sea
level section south OF Mirafiores locks.
both In building entertainments and in
various excavations that were made.
They were encountered early in the
construction of the and
Gatun dams.
,
In tho former, v 10 the weak
0trdLt underlying the surface. there
was caused II bulgins up outside Of the
emoankment. with "A consequent SET
Element r displacement OF h pile.
The sliD which occurred in the rock
pile which formed the southern toe OF
h portion of the Gatun lam near the
edge OF tho old French canal and
which brought forth SUCH adverse
criticism Of the project at h tim
was caused by dumping rock on a
comparatively soft and slippery ma
te11al.
On the relocation OF the Panama
Railroad high embellishments were built
.1,,,o,v .of, strata that could no, boar
the pressure transmitted to them by
the superimposed masses.
Depending upon "a" causes. ths
0lides which were encountered Will,
~excsvating for the locks and the cana
prism were of three distinct classes
First, those CAUSED by the material as
Stunning its natural slope, in cases
where the banks were left sleeper than
the angle of epose for the particular
material through which the "xcava-
ton was carried.
Second, those Ii 10 h fact that
material more or less permeable re-
posed on relatively harder strata
which inclined toward the cutting
When the excavation reached a leve.
near or below the intersection OF tn,
harder plane with tho sides of the
prAs1n tho superimposed mass moved
into the e~xcavated area.
Third. those which resulted from IN.
NresL,ng Of weak strata under,vip, ~,
hanks r,,n,ure heinr nroduced nv W.
corccn+r,tinn nf I'm. v,,rh,s or ~,
hapls duo IN tho reuovo ~ tho VA
.n,'ar ,rnu I'm. nrism ~