2. INTRODUCTION
In the Cone Penetration Test
(CPT), a cone on the end of
a series of rods is pushed
into the ground at a
constant rate and
continuous measurements
are made of the resistance
to penetration of the cone
and of a surface sleeve.
3. BEST SUITED FOR
CPT BEST SUITED FOR
I. Sand,
II. Silt,
III. Clay,
IV. Residual soil
4. OBJECTIVES
The objectives of any subsurface investigation
are to determine the following.
Nature and sequence of the subsurface strata
(geologic regime)
Groundwater conditions (hydrologic regime)
Physical and mechanical properties of the
subsurface strata
5.
6. TEST EQUIPMENT
CONE PENETROMETERS
Cone penetrometers come in a range of sizes with
the 10 cm2 and 15 cm2 probes the most common
and specified inmost standards. Fig shows a range
of cones from a mini cone at 2cm2 to a large cone of
40cm2. The mini cones are used for shallow
investigations, whereas the large cones can be used
in gravely soils.
7.
8.
9. Used to determine the Geotechnical Engineering
properties of soil.
Defining soil stratigraphy,homogeneity and depth to
firm layers, voids or cavities, and other discontinuities.
It was initially developed in the 1950s at the Dutch
Laboratory for Soil Mechanics in Delft to investigate soft
soils.
Based on this history it has also been called the "Dutch
cone test".
Today, the CPT is one of the most used and accepted
in soil methods for soil investigation world wide.
10. (Continue……………)
The test method consists of pushing an
instrumented cone.
Whose tip facing down, into the ground.
The purpose of the CPT in defining
stratigraphic layers is related to the size of the
cone tip.
Diameters of 3.6 and 4.4 cm we mostly use
