Sachpazis Costas: Geotechnical Engineering: A student's Perspective Introduction
Cone Penetration Test
1. Collage of Engineering
Civil Engineering Department
CLE614 Soil Dynamics
Title : Cone Penetration Test
Submitted to : Dr. Yeşim Gürtuğ
ID : 20153680By : Muftah Aljoat
ID : 20152843Adel Milad
May/2016
2. History of CPT
Introduction
Information about CPT
CPT device consists
Usage of CPT
Process of CPT
Advantages & Disadvantages
Conclusion
3. First develop in 1930’s as mechanical cone.
Electric cones develop in 1960’s.
Primary device for offshore investigations since
1970’s .
4. CPT in this time is the most used and accepted in-
situ test methods for soil investigation world wide.
It is to determine the Geotechnical engineering
properties of soils.
It was used in 1950s at the Dutch Lab for soil
Mechanics so that it has also been called the
( Dutch cone test ) .
5. In (CPT), a cone on the end of a series of rods is pushed into the ground with
constant rate .
continuous measurements are made of the resistance to penetration of the
cone and a surface sleeve.
( Fig 1)
7. CPT are conducted to measure and evaluate
characteristics of specific soils (soft sensitive silt sand,
clay, and some coarse cohesion less soils) such as:
1. Soil type
2. Relative soil density and in-situ stress conditions
3. Shear strength parameters
8. After analyzing the results obtained from the test, we can
determine the soil type and design of shallow foundations
through the estimation of stiffness and shear strength of
cohesive soils.
The results from CPT may also be used, directly, for
design of piled foundations in sand and gravel.
Indirectly, it can be used (shear strength) for piles in clay.
9. Fig 2 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.
( Fig 2) Types of cone
12. Advantages
• Rapid test
• Economy
• identification of problem soils
• Detailed & precise data
• Real time measurement
Disadvantages
• Soil sample not obtained
• Depth limited
• Normally can’t push through
gravel
• Requires special equipment
and skilled operator
13. Save money for the owner by more accurately identifying the geological
strata.
Seismic evaluations can be done to satisfy the new building code
requirements by measuring the low strain for shear wave velocity.
Can be used to predict vertical pile capacity.
In normally consolidated or recently aged cohesion less soils, provides
good estimates of settlement for shallow foundations.
14. Cone Penetration Testing in Geotechnical Practice written by
Tom Lunne, John J.M. Powell, and Peter K. Robertson.
Howstuffworks.com
Southern Earth Sciences,.Inc
subsurface exploration using the cone penetrometer test
(paper)
Cone Penetrometer Test (paper)
14
Editor's Notes
Role of CPT
Estimate soil parameters
Provide results for direct geotechnical design
role of CPT
Estimate soil parameters
Provide results for direct geotechnical design
