scholarly journals In situ strength characterisation of peat and organic soil using full-flow penetrometers

2011 ◽  
Vol 48 (7) ◽  
pp. 1085-1099 ◽  
Author(s):  
N. Boylan ◽  
M. Long ◽  
F.A.J.M. Mathijssen
Keyword(s):  
Organic Soil ◽  
Cone Penetrometer ◽  
Uniform Measure ◽  
In Situ Testing ◽  
Strength Parameters ◽  
Resistance Factors ◽  
Fibrous Peat ◽  
Penetration Tests ◽  
Range Of Values

Full-flow penetrometers have been shown to overcome problems experienced with the cone penetrometer when measuring resistance in very soft peat and organic soil, and give a much more uniform measure of resistance than the cone in fibrous peat. However, at present there is no guidance on the interpretation of strength parameters in these soils using the T-bar and ball. This paper examines the results of tests using these devices at two research sites in the Netherlands in conjunction with high-quality Sherbrooke sampling for laboratory testing. In fibrous peat, the T-bar and ball provided a more uniform measure of resistance with a lower degree of scatter than the cone. The in situ testing results have been compared with the laboratory tests to assess the range of resistance factors relating penetration resistance to the undrained shear strength (su) and have been shown to occupy a lower range of values than the cone penetrometer. However, penetration tests in these soils are likely to be influenced by partial drainage effects and this should be considered during testing and the subsequent interpretation of results. Recommendations are made for the use of full-flow penetrometers to obtain strength parameters in these soils.

scholarly journals CPT Profiling and Laboratory Data Correlations for Deriving of Selected Geotechnical Parameter

2015 ◽  
Vol 11 (2) ◽  
pp. 152-157 ◽  
Author(s):  
Roman Bulko ◽  
Marián Drusa ◽  
Jozef Vlček ◽  
Martin Mečár
Keyword(s):  
Laboratory Data ◽  
Cost Effective ◽  
Soil Samples ◽  
Geological Survey ◽  
Testing Time ◽  
In Situ Testing ◽  
Time Saving ◽  
Dynamic Penetration ◽  
Penetration Tests

Abstract Currently, can be seen a new trend in engineering geological survey, where laboratory analysis are replaced by in situ testing methods, which are more efficient and cost effective, and time saving too. A regular engineering geological survey cannot be provided by simple core drillings, macroscopic description (sometimes very subjective), and then geotechnical parameters are established based on indicative standardized values or archive values from previous geotechnical standards. The engineering geological survey is trustworthy if is composed of laboratory and in-situ testing supplemented by indirect methods of testing, [1]. The prevalence of rotary core drilling for obtaining laboratory soil samples from various depths (every 1 to 3 m), cannot be a more enhanced as continues evaluation of strata and properties e.g. by CPT Piezocone (every 1 cm). Core drillings survey generally uses small amounts of soil samples, but this is resulting to a lower representation of the subsoil and underestimation of parameters. Higher amounts of soil samples make laboratory testing time-consuming and results from this testing can be influenced by the storage and processing of the soil samples. Preference for geotechnical surveys with in situ testing is therefore a more suitable option. In situ testing using static and dynamic penetration tests can be used as a supplement or as a replacement for the (traditional) methods of surveying.

Interpretation of in situ test results from the CANLEX sites

2000 ◽  
Vol 37 (3) ◽  
pp. 505-529 ◽  
Author(s):  
C E (Fear) Wride ◽  
P K Robertson ◽  
K W Biggar ◽  
R G Campanella ◽  
B A Hofmann ◽  
...  
Keyword(s):  
Shear Wave ◽  
Wave Velocity ◽  
Shear Wave Velocity ◽  
Soil Liquefaction ◽  
In Situ Testing ◽  
Cone Penetration ◽  
In Situ Tests ◽  
Cone Penetration Tests ◽  
Penetration Tests

One of the primary objectives of the Canadian Liquefaction Experiment (CANLEX) project was to evaluate in situ testing techniques and existing interpretation methods as part of the overall goal to focus and coordinate Canadian geotechnical expertise on the topic of soil liquefaction. Six sites were selected by the CANLEX project in an attempt to characterize various deposits of loose sandy soil. The sites consisted of a variety of soil deposits, including hydraulically placed sand deposits associated with the oil sands industry, natural sand deposits in the Fraser River Delta, and hydraulically placed sand deposits associated with the hard-rock mining industry. At each site, a target zone was selected and various in situ tests were performed. These included standard penetration tests, cone penetration tests, seismic downhole cone penetration tests (giving shear wave velocity measurements), geophysical (gamma-gamma) logging, and pressuremeter testing. This paper describes the techniques used in the in situ testing program at each site and presents a summary and interpretation of the results.Key words: CANLEX, in situ testing, shear wave velocity, geophysical logging, pressuremeter.

scholarly journals Instrumented Impact Cone Penetrometer

1973 ◽  
Vol 10 (3) ◽  
pp. 397-409 ◽  
Author(s):  
Umesh Dayal ◽  
John H. Allen
Keyword(s):  
Field Tests ◽  
Strength Properties ◽  
Experimental Program ◽  
Cone Penetrometer ◽  
Test Results ◽  
In Situ Testing ◽  
Penetration Mechanism ◽  
Side Friction ◽  
Local Side

The present paper describes the development of an instrumented impact cone penetrometer for a direct measurement of in situ strength properties of a soil target. The developed penetrometer, in addition to providing acceleration signatures (as obtained by previous investigators), is capable of recording cone thrust and local side friction simultaneously and continuously. The procedures have been outlined for estimating in situ strength properties and soil type of the target materials throughout the penetrated depth from the output records of these sensors. Typical test results generated from an on-going experimental program aimed at providing the data for (1) understanding the penetration mechanism, (2) development of penetration theory, and (3) designing the penetrometer for field tests, i.e. in situ testing of ocean floor soils, are also presented.

Guidance on Pressuremeter, Flat Dilatometer and Cone Penetration Testing

1986 ◽  
Vol 2 (1) ◽  
pp. 223-233 ◽  
Author(s):  
P. S. Finn ◽  
R. M. Nisbet ◽  
P. G. Hawkins
Keyword(s):  
Cone Penetrometer ◽  
Cone Penetration ◽  
In Situ Tests ◽  
Cone Penetration Tests ◽  
Cone Penetration Testing ◽  
The United Kingdom ◽  
Different Types ◽  
Cone Penetrometer Testing ◽  
Penetration Tests

AbstractBS 5930 provides little guidance on the specification, practice and interpretation of pressuremeter, flat dilatometer and cone penetration tests. This paper describes certain key elements in the successful use of such tests which are frequently overlooked in practice. The different types of pressuremeter available in the United Kingdom are reviewed and the importance of care in the installation of pressuremeters of all types is highlighted. The principles of operation of the flat dilatometer are presented and comments made on the interpretation and application of results. Cone penetrometer testing and the types of equipment available are also discussed. The necessity for frequent and thorough calibration of all testing devices is emphasised and requirements for data presentation and reporting of these in situ tests are indicated.

Piezo-friction-cone penetrometer testing in soft clays

1987 ◽  
Vol 24 (4) ◽  
pp. 645-652 ◽  
Author(s):  
J.-M. Konrad
Keyword(s):  
Pore Pressure ◽  
Water Pressure ◽  
Testing Procedure ◽  
Soil Conditions ◽  
Cone Penetrometer ◽  
In Situ Testing ◽  
Soft Clays ◽  
Tip Resistance ◽  
Full Design

A comprehensive in situ testing program using a 50-kN electric piezo-friction-cone penetrometer was carried out at three different sites in soft marine clays. In these soils, the measured penetration resistance and friction are less than 4% of the full design capacity of the load cells. Although the strain gauges are temperature compensated, the importance of temperature effects in these soil conditions is demonstrated. The paper outlines a testing procedure to minimize the errors associated with zero shift in cone testing and to obtain meaningful data in weak soils with 50-kN penetrometers.Pore-water pressure measurements along the shaft are essential to evaluate the in situ test results in soft soils. Pore pressure distribution along the shaft is dependent on soil type, and measurements should be made at both ends of the friction sleeve for complete soil characterization.Friction along the shaft is not uniform and is negligible over an initial length of about 2 cone diameters in soft clays. Key words: soft clays, pore pressure, friction, tip resistance, in situ testing.

scholarly journals Soil suitability estimation for housing purposes in landslide-prone areas. The case of Karya village, Patras, W. Greece

2007 ◽  
Vol 40 (4) ◽  
pp. 1683
Author(s):  
G. Koukis ◽  
N. Sabatakakis ◽  
S. Lainas
Keyword(s):  
Shear Strength ◽  
Slope Stability ◽  
Limit Equilibrium ◽  
Shear Strength Parameters ◽  
In Situ Testing ◽  
Strength Parameters ◽  
Soil Suitability ◽  
The City ◽  
Heavy Rainfalls

This paper discusses a method of soil suitability estimation for housing purposes in landslide-prone areas based on engineering geological criteria. The studied places, Karya and Neo Souli villages are located on the eastern part of the city of Patras. Several instability problems were identified triggered by heavy rainfalls, especially during extreme meteorological events. The soil formations were classified in several geotechnical units while typical geotechnical profiles and slip sections were drawn. Limit equilibrium slope stability analyses were established in order to investigate the critical slide conditions, using shear strength parameters estimated from laboratory and in-situ testing. The studied area was finally divided into five zones according to the suitability of the encountered ground regarding housing purposes

Sign in / Sign up

Export Citation Format

Share Document