Collage of EngineeringCivil Engineering Department

CLE614 Soil Dynamics

Title : Cone Penetration Test

Submitted to : Dr. Yeşim Gürtuğ

ID : 20153680 By : Muftah Aljoat

ID : 20152843 Adel MiladMay/2016

History of CPT

Introduction

Information about CPT

CPT device consists

Usage of CPT

Process of CPT

Advantages & Disadvantages

Conclusion

Table of Content

First develop in 1930’s as mechanical cone.

Electric cones develop in 1960’s.

Primary device for offshore investigations since

1970’s .

History of CPT

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 ) .

Introduction

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.

about CPT Information

(Fig 1)

CPT device consists

video 1 CPT device consists

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

Usages of CPT

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.

CONT…

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.

Typical Cone Sizes

(Fig 2) Types of cone

Engine Operated (200KN) Hand Operated (30KN)

(Fig 3)

Process of CPT

(Fig 4)

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

Assessment of CPT

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.

Conclusion

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

Some Key References