A
APPLICATIONS
Ø To determ
mine how roo
of or wall
NGLE PO
SIN
OINT ME
ECHANIC
CAL
BOREHOLE
E EXTEN
NSOMET
TER
MOD
DEL EDS--64U/D
OVERVIEW
O
The
T Encardio-rite model EDS-64U/D
E
single position
n mechanical borehole
extensometer
e
r is suitable for 50 mm
m upward, d
downward orr inclined
boreholes.
b
It is a precision mechanica
al instrument designed to help civil
engineers
e
and
d geologists in the measurrement of defformation of ro
ock mass
and
a adjacent or surroundin
ng soil. Toge
ether with ancchor bolt load
d cell and
tape extenso
ometer, it is
s essential equipment ffor investiga
ation and
monitoring
m
of foundations,, slopes & embankments and for stud
dying the
behavior
b
of rock around underground cavities, tun
nnels and miines. The
borehole
b
exttensometer is an imp
portant instru
ument espe
ecially in
in
nvestigation of
o undergroun
nd cavities an
nd landslides.
DESCRIPTIO
D
ON
The
T
borehole extensom
meter measu
ures the
extension
e
(dissplacement) which
w
takes place
p
with
time in a bore
ed hole or in several
s
bored
d holes in
a rock mass. It essentially consists of an
a anchor
grouted
g
in a borehole and a
reference
r
pla
ate. They help to
accurately
a
measure the distance
between
b
the anchor with respect
to the referen
nce plate and monitor
their relative displaceme
ent with
passage
p
of time.
t
The ch
hange in
displacement
d
between the
e anchor
and
a
reference
e plate is ac
ccurately
monitored
m
witth passage off time. It
iss usually assumed that the
e anchor
iss in stable ground and so any
change
c
in the
t
anchor spacing
gives
g
informattion about the
e settlement of
o foundation taking place.
MEASUREME
M
ENT METHOD
The
T
measurrement with model ED
DS-64U/D single point borehole
extensometer
e
r is economical, reliable
e and is esssentially preferred at
lo
ocations whe
ere access to
o the mouth of
o the boreho
ole is easily available.
Displacement
D
t readings are
e taken by me
easuring the depth of the near end
of
o the connec
cting rod from
m a reference plate provide
ed at the mou
uth of the
borehole.
b
A digital caliper/m
micrometer depth gage wiith a resolutio
on of 0.01
mm
m is used to
o take the readings.
EDS-64U/D
E
SINGLE PO
OSITION EX
XTENSOMET
TER
The
T
model EDS-64U/D
E
s
single
positio
on borehole extensometer can be
in
nstalled in a 2”
2 φ NX (50 mm
m φ) borehole.
of an un
nderground cavity
c
or
tunnel
behaves
during
n operation and to
excavation
study the effectivenesss of the
support sy
ystem.
Ø To
mea
asure and monitor
settlement in a founda
ation due
ation of unde
erground
to excava
cavities or due to con
nstruction
of a he
eavy structu
ure like
concrete, rock-fill, masonry or
earth dam
m over the foundation.
G
GROUTABLE
E ANCHOR
A
At locationss where th
he rock
fformation is soft or lots of water
e
exists, it is not
n possible to install
e
expandable anchor efffectively.
G
Groutable an
nchor is ideally suited
ffor such applications. In a
borehole, it is
b
i usual to use
u
a 20
m
mm φ, 500 mm long groutable
g
a
anchor.
EXTENSOME
ETER SYSTE
EM
DESCRIPTIO
ON
T
The groutable reinforcced bar
a
anchor (1) iss attached to SS 410
sstainless ste
eel (φ 8 mm) or
ffiberglass (φ
φ 6 mm) co
onnecting
rrods (2) of appropriate
a
le
ength, as
sspecified in th
he design.
T
The anchorr is inserted into
the
along
with
b
borehole
cconnecting rod and fixed
f
in
p
out. The
position by cement gro
cconnecting ro
od is protectted from
tthe cement grout
g
by enclosing in
h
heavy duty PVC protecttive tube
((3), thus allowing fo
or free
movement an
m
nd displaceme
ent.
T
The extensio
on head conssists of a
rreference head assemblyy (6) and
a protective cover assem
mbly (13).
T
The referenc
ce head asse
embly is
g
grouted co
oncentric w
with the
b
borehole. The referencce head
a
assembly ha
as four exp
pandable
g
grouting anch
hors (11) for fastening
f
tthe extensometer head to the
ssurface of the
e borehole.
The
T
PVC pro
otective tube (3), grout tube (5) and a
air EXTENS
SOMETER A
ASSEMBLY
vent
v
tube (4) are secured to the refere
ence head witth
Item Description
D
rubber
r
washe
ers (7 & 8) and
a
hollow bo
olts (7 & 9) tto
A
Anchor
( 20 mm
m Ø x 500 mm
m length)
make
m
the systtem leak proo
of. A referencce plate (12) is 1
C
Connecting
rod
d (SS Ø 8 mm
m /fiberglass
used
u
to meas
sure the displa
acement of th
he anchor from 2
Ø
6.3
mm
a
assembly
with
h protective
the reference button (10) fixed
f
on the connecting
c
ro
od
tu
ube)
o-rite uses convention that
t
depth of
(2). Encardio
P
PVC
protective
e tube for SS connecting
anchor
a
is calcculated as distance from th
he mouth of th
he 3
ro
od
(o.d.-14
m
mm
x 2 mm thiick)
hole
h
to the near end of anc
chor.
4
A vent tube (o
Air
o.d.-12 mm x 1 mm thick)
12
10
9
8
7
6
5
4
152
11
117
13
3
2
Qty
1
#
#
●
5
G
Grout
tube (o.d.-12 mm x 1 mm thick)
●
6
R
Reference
hea
ad assembly
1
7
Rubber bush for
R
tu
ube/connectin
ng rod
8
W
Washer
3
9
H
Hollow
bolt forr air vent/grou
ut tube
3
10
R
Reference
buttton
1
11
Expandable A
E
Anchor M12
2x145 with
w
washer
& nut
4
12
Reference p
R
plate
a
accessories
1
13
P
Protective
covver Assembly
#
Q
Quantity
depends upon dep
pth of anchor
●
L
Length
varies from applicattion to applica
ation
air
with
vent/gout
mounting
3
1
ORDAER
RING CODE
E & INFORM
MATION
EDS-64 U/D-X-Y-Z
U
Depth of an
nchor in mete
er
Ran
nge of Digital caliper/depth
h
gag
ge
1
S: S
Stainless stee
el connecting rod
F: F
Fiberglass co
onnecting rod
U: Upward moun
nting
ntal
D: Downward orr near horizon
mounting
Ø50 mm
m
*All specification
*
ns are subject to change withoutt prior notice. ENCA
ARDIO-R
RITE ELECTRON
NICS PV
VT. LTD.
A-7
7 Industrial Es
state, Talkatora Road, Luckn
now, UP-226011, India
p +91
1 522 2661040, f +91 522 266
62403, email: geotech@enc
cardio.com
International:
I
61044,
p +91 522 266
www.en
ncardio.com
HEET 1220-12 R00
DATA SH