Post on 14-Apr-2018
7/27/2019 Presentation SPT
1/26
7/27/2019 Presentation SPT
2/26
STANDARD PENETRATION TEST
7/27/2019 Presentation SPT
3/26
WHAT IS SPT?
Dynamic penetration test carried out using a
standard procedure which described in BS
1377-9: 1990
As an indicator of the density and
compressibility of granular
7/27/2019 Presentation SPT
4/26
HOW SPT WORK?
Use a thick-walled sample tube.
Driven into the ground at the bottom of the
borehole by blows
Blow count gives an indication of the density of
the ground
the small sample that is recovered will havesuffered some disturbance but can normally be
used for identification purposes.
7/27/2019 Presentation SPT
5/26
7/27/2019 Presentation SPT
6/26
WHY USED SPT?
To provide an indication of the relative densityof granular deposits, such
as sands and gravels from which it is virtually
impossible to obtain undisturbed samples.
simple and inexpensive
7/27/2019 Presentation SPT
7/26
CONE PENETRATION TEST
7/27/2019 Presentation SPT
8/26
7/27/2019 Presentation SPT
9/26
7/27/2019 Presentation SPT
10/26
CONE PENETRATION TEST CAN IN PRINCIPLE BE
USED TO EVALUATE:
type of soil
soil density and in-situ stress conditions
shear strength parameters. the liquid limit and plastic limit of soil sample
material properties
7/27/2019 Presentation SPT
11/26
HOW CPT WORK?
The test is performed using a cylindrical penetrometerwith a conical tip (cone) penetrating the ground at aconstant rate.
During the penetration, the forces on the cone and thefriction sleeve are measured.
The measurements are carried out using electronictransfer and data logging, with a measurement frequencythat can secure detailed information about the soilconditions.
The test method consists of pushing an instrumentedcone, with the tip facing down, into the ground at acontrolled rate (controlled between 1.5 -2.5 cm/saccepted).
7/27/2019 Presentation SPT
12/26
HOW CPT WORK?
7/27/2019 Presentation SPT
13/26
EQUIPMENT OF CPT
A cylindrical probe with a con-shaped tip with
different sensors that allow continuous
measurement of soil strength and
characteristics.
7/27/2019 Presentation SPT
14/26
TRIAL PIT
7/27/2019 Presentation SPT
15/26
TRIAL PITAn excavation of ground in order to study or
sample the composition and structure of the
subsurface.
Expensive, take time to excavate and are not
always as informative as expected.
7/27/2019 Presentation SPT
16/26
Dug during a site investigation, a soil survey
or a geological survey.
Dug before the construction. (to determine
the geology and the water table of that site)
7/27/2019 Presentation SPT
17/26
Starting size for a pit depends on the depth it
is to be sunk
Decide the depth and information to be
sought and whether other means before start
the trial pit.
1 and 4 meter deep.
Dug by hand or using a mechanical digger.
7/27/2019 Presentation SPT
18/26
7/27/2019 Presentation SPT
19/26
Can be extended into tranches to trance any
particular feature. (very efficient and
economical)
Rapid check on the condition of the ground
can be check if there is no side support.
(unsafe but the technician can prepare a
visual log of strata)
7/27/2019 Presentation SPT
20/26
Tube samples can be driven into the floor of
the pit using a jarring link drill rods.
7/27/2019 Presentation SPT
21/26
In-situ-testing also can be carried out. (must
do fast before the pits collapse)
Vane Shear Strength Test
7/27/2019 Presentation SPT
22/26
Since open pits can be hazard to others, it is
encouraged to backfill pits as soon as
possible.
There is an advantage if we leaving pits
fenced, shored and open. ( allow the
excavated surface to partially dry)
7/27/2019 Presentation SPT
23/26
ADVANTAGES DISADVANTAGES
Preferred for cohesive soiland soft rock
Showing clear land strata to
facilitate rough inspections
Easy dug / excavated usingdiggers
Depth is limited Deeper excavation will
require the human energy
7/27/2019 Presentation SPT
24/26
TRIAL PITTING SAFETY GUIDANCEA competent person must supervise the work
and operatives must be given clear
instructions on working safely when near
excavations.
If there is a risk of contact with buried
services then up-to-date utility drawings must
be consulted prior to carrying out anyground-works.
7/27/2019 Presentation SPT
25/26
A cable avoidance tool should be used to
locate the buried cables and a hand dug trial
pit shall be excavated if in doubt.
The excavated sides must be prevented from
collapse either by digging a safe angle or by
shoring with timber or support systems.
Whenever possible, the workings should becovered outside work hours.
7/27/2019 Presentation SPT
26/26
THANK YOU
MOHAMAD IZZUDDIN BIN BORHANUDDIN 15DKA11F2045
NUR NADHIRAH IZYAN BINTI AZMAN 15DKA11F2049
MOHAMAD AMERUDDIN BIN MADROM 15DKA11F2053
ZURHAINI HANOM BINTI ALI UMAR
15DKA11F2041 MUHAMAD NURAIMAN BIN MD ZAINI
15DKA11F2055