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Design and development of a tractor-mounted, recording penetrometerJayatissa, D. Nimal January 1986 (has links)
As part of a long term study dealing with the effect of continuous use of no-till practice on soil structural characteristics, this study was conducted with the following objectives: (i) to design and develop a tractor-mounted, hydraulically-operated, recording penetrometer, (ii) to collect the initial penetration resistance data from the experimental plots established for the long term study.
A penetrometer assembly was designed and constructed with the capability of collecting penetration resistance across two crop rows. At any point, the penetration resistance data could be collected up to a depth of 60 cm. A simple hydraulic circuitry was developed to control the rate of penetration at 3 cm/s.
A micro-computer based data acquisition system was developed to record the penetration resistance and depth data during each penetration test. This data acquisition system together with a cassette tape recorder could record the data from large number of tests under field conditions. The data stored on the tape could be transferred to a personal computer for data reduction and analysis.
Field tests were conducted to evaluate the system developed and to establish the initial data for the experimental plots established for long term study. Results of these tests indicated that the system functioned satisfactorily and there exists significant difference in penetration resistance from plot to plot and as a function of depth within each plot. / M.S.
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Strength-balance of bitumen stabilised pavements.Van Wyk, Schalk Willem. January 2013 (has links)
M. Tech. Engineering: Civil. / Discusses the objective of this study was to develop an equation to determine the penetrometer penetration rate (DN) of a pavement consisting of Bitumen Stabilised Material layers are constructed. The aim is to use laboratory results of Bitumen Stabilised Material and study the relations between the Indirect Tensile Strength and the Unconfined Compressive Strength. With the relations a penetrometer penetration rate (DN value in millimetre per blow) can be determined. This will enable the designer to apply the strength-balance concept on a pavement consisting of Bitumen Stabilised Materials. As indicated previously it was found during the design stages that only the Indirect Tensile Strength data on the Bitumen Stabilised Material was available. Developing an equation to convert the Indirect Tensile Strength data to a DN value will allow the designer to apply the strength-balance concept and adjust the design for improved performance life of a pavement.
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Use of the mini-cone penetrometer for evaluating the liquefaction potential of sands associated with Charleston, S.C. seismic eventsDickenson, Stephen Eugene 21 July 2010 (has links)
First-hand reports on the 1886 Charleston earthquake contain numerous accounts for the widespread occurrence of liquefaction related features in and near the meizoseismal zone. Recent geologic studies have found evidence for the repeated liquefaction of sandy soils in the Charleston area due to recurring large seismic events. In the course of this investigation 24 mini-cone penetration tests were performed at seven sites in or near the meizoseismal zone of the 1886 earthquake to determine the factors influencing ground failures due to liquefaction. These tests were supplemented with soil borings, sieve tests and a limited number of standard penetration tests to aid in characterization of the sandy soils. Additionally, soil boring records in Charleston were obtained which provided in-situ testing data in an area with documented historical damage. The range of sites at which testing was done, or information was available, represent locations experiencing various levels of liquefaction and distances from the zone of seismic energy release.
Penetration data were used to evaluate resistance of the sandy soil to cyclic loading and fonned the basis for assessing the effects that the lateral extent and distribution of loose sand layers has on the surficial manifestation of liquefaction. With the absence of cementation and extensive soil development, soils as old as late Pleistocene age have been found to be very susceptible to liquefaction. At several sites these soils have undergone at least three episodes of liquefaction and presently exhibit low penetration resistances, indicating that the progressive densification of a liquefiable soil layer can be minor unless it is in very close proximity to a large venting feature. The size and density of occurrence of vents and sand blows has been found to be primarily dependent on the extent of both the liquefiable layer and any overlying resistant layers. Layered system relations utilized with field performance data, and historical and geologic evidence for the occurrence of liquefaction features to suggest that the near surface peak horizontal accelerations induced by the 1886 earthquake were approximately O.3g in the meizoseismal zone and O.2g in the city of Charleston. This is in contrast with previous estimates of seismic shaking all of which point toward values in the range of 0.5 to O.6g. The reason for the different acceleration estimates is not clear at this time, and will be further studied in future extension of this work. / Master of Science
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Kayma direnç parametrelerinin sismik hızlar ile belirlenmesi /Çekmen, Veysel. Uyanık, Osman. January 2009 (has links) (PDF)
Tez (Yüksek Lisans) - Süleyman Demirel Üniversitesi, Fen Bilimleri Enstitüsü, Jeofizik Mühendisliği Anabilim Dalı, 2009. / Kaynakça var.
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Caracterização da resistência de um solo tropical a partir do ensaio de penetração dinâmica de cone com energia variável (panda) / Resistance characteristics of a tropical soil from a dynamic cone penetration test with variable power (panda)Diemer, Francielle 08 August 2014 (has links)
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Previous issue date: 2014-08-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Get soil resistance is critical to making any geotechnical design with confidence, thus,
laboratory tests are used to determine the strength and deformability of the ground in discrete
points involved in the volume of soil mass. Due to heterogeneity of soil formation is that field
trials are needed to supplement this determination and enrich the bank information. Field trials
were able to identify and estimate the mechanical parameters of the soil, an adequate prediction
of the behavior of retaining structures, excavation, foundation, floor sizing, etc., and determine
the characteristics of the soil profile, and have was used to estimate the mass of strength
parameters involved ground. In this sense a new tool for the characterization of the soil profile
from dynamic penetration of a metal cone with variable energy (PANDA) has been studied to
find a relationship with the strength parameters of a tropical soil obtained in a vertical slope of
about 4, 0 m high, located in Alexânia - GO with sandy visual tactile characteristics. Therefore,
we performed PANDA tests up to 4.0 meters and determining the moisture profile through a
survey to auger up to 3.70 meters and laboratory characterization tests were performed,
determining the strength parameters in natural moisture condition and flooded , deformation
parameters and determination of soil water characteristic curve (CCSA). PANDA the results
were compared with the laboratory tests for this ground and found a range of variation between
them always considering the trials of natural moisture condition. With the results it was possible
to see the influence of suction in the PANDA test. In terms of resistance parameters was
possible to find a friction angle of the relationship with the penetration of energy (qd) for this
soil. Overall the strength parameters showed the same trend as the qd values obtained by
PANDA compared with respect to depth. Finally, with the results it is recommended to carry
out further testing on different soil types in different humidity conditions to improve relations
found and increase the database. / Obter a resistência do solo é fundamental para elaborar qualquer projeto geotécnico com
confiança, sendo assim, ensaios de laboratório são usados para determinar a resistência e
deformabilidade do solo, em pontos discretos no volume da massa de solo envolvido. Devido
a heterogeneidade da formação do solo é que são necessários ensaios de campo para
complementar essa determinação e enriquecer o banco de informações. Os ensaios de campo
são capazes de identificar e estimar os parâmetros mecânicos do solo, para uma adequada
previsão do comportamento de estruturas de contenção, escavações, fundações,
dimensionamento de pavimentos, entre outros, além de determinar as características do perfil
do solo, e têm sido utilizados para estimar parâmetros de resistência do maciço de solo
envolvido. Nesse sentido uma nova ferramenta para caracterização do perfil do solo a partir de
penetração dinâmica de um cone metálico com energia varíavel (PANDA) foi estudado para
encontrar uma relação com os parâmetros de resistência de um solo tropical obtido em um
talude vertical de aproximadamente 4,0 m de altura, localizado em Alexânia – GO, com
características tatil visuais arenosas. Para tanto foram realizados ensaios de PANDA até 4,0
metros e determinação do perfil de umidade através de uma sondagem à trado até 3,70 metros
e em laboratório foram realizados ensaios de caracterização, determinação dos parâmetros de
resistência na condição de umidade natural e inundado, parâmetros de deformação e
determinação da curva característica solo água (CCSA). Foram comparados os resultados do
PANDA com os ensaios de laboratório para este solo e encontrou-se uma faixa de variação
entre eles sempre considerando os ensaios da condição de umidade natural. Com os resultados
encontrados foi possível ver a influência da sucção no ensaio PANDA. Em relação aos
parâmetros de resistência foi possível encontrar uma relação do ângulo de atrito com a energia
de penetração (qd) para este solo. No geral os parâmetros de resistência apresentaram a mesma
tendência que os valores de qd obtidos pelo PANDA quando comparados em relação a
profundidade. Por fim, com os resultados encontrados recomenda-se realizar mais ensaios com
diferentes tipos de solo em diferentes condições de umidade para melhorar as relações
encontradas e aumentar o banco de dados.
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Scaling effect in cone penetration testing in sandEid, Walid Khaled January 1987 (has links)
The Cone Penetration Test (CPT) was developed originally in Holland in the 1930’s as a device which provides a small scale model of a pile foundation. Early versions were simple cone points for which the only measurement was the thrust required to push the point through the ground. Over the past 20 years, the cone was standardized to a tip area of 10 cm², and an electrical version was produced, which allows for continuous measurement of the cone tip resistance and sleeve friction along with a computer-based data acquisition system. The electrical cone represents a significant step forward for the CPT, since it provides a continuous profile of information that can be used to identify soil type and define important engineering parameters. More recently, the CPT has shown considerable potential for calculation of settlements of footings on sand, determination of pile capacity, assessment of ground pressures, and evaluation of liquefaction potential for cohesionless soils.
Along with the widening application of the CPT, new varieties of cone penetrometers have appeared, with different sizes than the standard. Smaller cones are used for instances where relatively small depths of soil need to be penetrated, and larger cones have been developed for penetrating dense and gravelly soils. With the introduction of the new cones, there has been a tendency to assume that the methods for reducing CPT data for the standard sized cone can be extrapolated to the other sizes of cones. That is, it is assumed that there are no scale effects in cones of different sizes. While this may be true, to date, little direct evidence has been produced to support this view, and the issue is an important one from two points of view:
1. The present data analysis technology is based on that primarily from testing with a standard cone. lt is important to know if any changes are needed in this approach, or if the existing methods can be used with confidence for any size cone.
2. If it can be shown that no scale factor exists, then this will allow the use of new, smaller cones in experimentation in modem calibration chambers with the knowledge that the test results are applicable for the cones that a.re more widely used in practice. The smaller cones offer several advantages in this type of work in that they facilitate the research considerably by reducing the effort involved in sample preparation, and they are less likely to produce results influenced by boundary conditions in the chamber.
One of the major objectives of this research is to develop an insight into the issue of the scale factor caused by the use of different sizes of cones. This is accomplished through an experimental program conducted in a new large scale calibration chamber recently constructed at Virginia Tech.
Many of the latest developments in cone penetration testing have been forthcoming from testing done in calibration chambers where a soil mass can be placed to a controlled density under known stress conditions. To conduct the experimentation of this work, it was necessary to design, fabricate, and bring to an operational stage a calibration chamber. The Virginia Tech chamber is one of the largest in the world. A significant portion of the effort involved in this thesis research was devoted to this task. In particular, attention was devoted to the development of a system for placement of a homogeneous soil mass in the chamber, and the implementation of a microcomputer-based data acquisition unit to record and process the test results.
The scale effects investigation was performed using three different sizes of cone penetrometers in a test program conducted in the calibration chamber. Of the three cones, one is smaller than the standard with a tip area of 4.23 cm², one was a standard cone with a tip area of 10 cm², and one was larger than the standard cone with a tip area of 15 cm². A total of 47 tests were carried in the chamber using two different levels of confining stress and two different sand densities. The test results show that while a scale factor might exist, the degree of its influence on interpreted soil parameters for a practical problem does not appear significant. / Ph. D. / incomplete_metadata
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The miniature electrical cone penetrometer and data acquisition systemKwiatkowski, Terese Marie January 1985 (has links)
The static cone penetrometer is an in-situ testing tool which was originally developed to derive information on soil type and soil strength. More recently, it has found application in liquefaction assessment. Typical cone penetrometers are heavy duty devices which are operated with the assistance of a drill rig. However, this capacity is not necessary in the case of field studies of liquefaction, since liquefaction usually occurs at relatively shallow depths. This thesis is directed to the goal of the development of a miniature, lightweight cone penetrometer which can be used in earthquake reconnaissance studies related to liquefaction problems.
The research for this thesis involved four principal objectives:
1. Development of procedures to automatically acquire and process measurements from a miniature electrical cone;
2. Develop and perform tests in a model soil-filled bin to calibrate the cone;
3. Evaluate the utility and accuracy of the cone results as a means to assess conventional soil properties; and,
4. Conduct a preliminary evaluation of the cone results in the context of recently developed methods to predict liquefaction potential.
The work in regard to the first objective involved assembling and writing software for a microcomputer based data acquisition system. Successful implementation of this system allowed data from the tests to be rapidly processed and displayed. Calibration tests with the cone were carried out in a four foot high model bin which was filled ten times with sand formed to variety of densities. The sand used is Monterey No. 0/30, a standard material with well known behavioral characteristics under static and dynamic loading.
The test results showed the cone to produce consistent data, and to be able to readily distinguish the varying density configurations of the sand. Using the results in conventional methods for converting cone data into soil parameters yielded values which were consistent with those expected. Liquefaction potential predictions were less satisfying, although not unreasonable. Further research is needed in this area both to check the reliability of the prediction procedures and the ability to achieve the desired objectives. / M.S.
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Tip Resistance Of A Miniature Cone Penetrometer Using Triaxial Apparatus For Clean And Silty SandRaju, K V S B 06 1900 (has links)
The static cone penetration tests are quite extensively used for carrying out in-situ geotechnical investigations both for onshore and offshore sites especially where the soil mass is expected to comprise of either soft to medium stiff clays or loose to medium dense sands. The wide use of the cone penetration tests (CPT) in geotechnical engineering has resulted in a great demand for developing necessary correlations between the cone penetration resistance and different engineering properties of soils. The successful interpretation of the cone penetration test data depends mainly on the various empirical correlations which are often derived with the help of a controlled testing in calibration chambers. The calibration chambers have been deployed in various sizes (diameter varying from 0.55 m to 2.10 m) by a number of researchers. It is quite an expensive and time consuming exercise to carry out controlled tests in a large size calibration chamber. The task becomes even much more difficult when a sample comprising of either silt or clay has to be prepared. As a result, most of the reported cone penetration tests in calibration chambers are mainly performed in a sandy material. Taking into account the various difficulties associated with performing tests in large calibration chambers, in the present study, it is attempted to make use of a miniature static cone penetrometer having a diameter of 19.5 mm. This cone was gradually penetrated at a uniform rate in a triaxial cell in which a soil sample of a given material was prepared; the diameter of the cone was intentionally chosen smaller so that the ratio of the diameter of the cell to that of the cone becomes a little larger. Two different diameters of the cells, namely, 91 mm and 140 mm, were used to explore the effect of the ratio of chamber (cell) size to that of the cone size. In addition, the rate of penetration rate was also varied from 0.6 mm/minute to 6.0 mm/minute (the maximum possible rate for the chosen triaxial machine with the larger cell) to examine the effect of the rate of the penetration of the miniature cone on the tip resistance. By using the chosen experimental setup, a large number of static miniature cone penetrometer tests were carried out on four different materials, namely, (i) clean sand, (ii) sand with 15% silt, (iii) sand with 25% silt, and (iv) sand with 15% fly ash. The cone tip resistance for each material was obtained for a wide range of three different relative densities. The effective vertical pressure (σv) for the tests on different samples was varied in between 100 kPa and 300 kPa. The variations of the tip resistance with axial deformation in all the cases were monitored so as to find the magnitude of the ultimate tip resistance. In contrast to the standard cone, the diameter of the piston shaft was intentionally kept a little smaller than that of the cone itself so as to restrict the development of the piston resistance. For each cell (chamber) size, two different sizes of the pistons were used to assess the resistance offered by the penetration of the piston shaft itself. It was noted that the resistance offered by the chosen piston shaft is not very substantial as compared to that of the cone tip itself. Most of the experimental observations noted from the present experiments were similar to those made by the penetration of the standard size cone in a large calibration chamber. The ultimate tip resistance of the cone was found to increase invariably with an increase in the magnitude of σv. An increase in the relative density of the soil mass leads to an increase in the value of qcu. For the same range of relative densities, an addition of fly ash in the sample of sand, leads to a considerable reduction in the magnitude of qcu. Even with the addition of 25% silt, the values of qcu were found to become generally lower as compared to clean sand and sand added with 15% silt. An employment of a larger ratio of the diameter of the cell to that of the miniature cone leads to an increased magnitude of qcu. An increase in the penetration rate from 0.6 mm/min to 6.0 mm/min, was found to cause a little increase in the magnitude of qcu especially for sand added with fly ash and silt. The effect of the penetration rate on the results was found to increase continuously with a reduction in the rate of penetration. At higher penetration rates, in a range closer to those normally employed in the field (20 mm/sec), it is expected that the rate of penetration of the cone will not have any substantial effects on the magnitude of qcu for clean sands.
The magnitude of qcu obtained in this thesis at different values of σv for all the cases with the use of the miniature cone were compared with the two widely used correlations in literature. It is found that except for dense sands, in most of the cases, the present experimental data lie generally in between the two correlation curves from literature; for dense sands the measured values of qcu were found to be significantly lower than the chosen correlation curves. It was noted that with the use of the miniature cone penetrated in a given sample prepared in a triaxial cell, it is possible to obtain reasonably an accurate estimate of the tip resistance of the standard cone especially for loose to medium dense states of all the materials. Further, from the analysis of all the tests results, it was noted that approximately a linear correlation between qcu/σv and soil friction angle (φ) for different chosen materials exists provided the dependency of the φ on the stress level is taken into account. As compared to the standard cone penetrometer which is usually employed in the field, the miniature cone used in this study is expected to provide a little conservative estimate, of the tip resistance of the standard static cone penetrometer with reference to the different materials used in this study on account of the facts that (i) there is a reduced area behind the cone, (ii) the ratio of the diameter of the calibration chamber (cell) to that of cone is not very high, (iii) the chosen size of the cone is smaller than the standard cone, and (iv) the chosen penetration rate is much smaller than the standard rate of penetration.
Further, in the case of clean sand, an attempt has also been made in this thesis, with the help of a number of direct shear tests at different stress levels, to generate an expression correlating peak friction angle, critical state friction angle, relative density of sand and vertical effective stress. A correlation has been generated with the help of which, the value of peak dilatancy angle can be obtained from the known values of peak friction angle and critical state friction angle. In confirmation with the available information in literature, this exercise on clean sand has clearly indicated that a decrease in the magnitude of vertical effective stress leads to an increase in the values of both peak friction angles and peak dilatancy angles.
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Engineering Characteristics of Sensitive Marine Clays - Examples of Clays in Eastern CanadaNader, Athir 28 February 2014 (has links)
Sensitive marine clay in Ottawa is a challenging soil for geotechnical engineers. This type of clay behaves differently than other soils in Canada or other parts of the world. They also have different engineering characteristic values in comparison to other clays. Cone penetration testing in sensitive marine clays is also different from that carried out in other soils. The misestimation of engineering characteristics from cone penetration testing can result. Temperature effects have been suspected as the reason for negative readings and erroneous estimations of engineering characteristics from cone penetration testing. Furthermore, the applicability of correlations between cone penetration test (CPT) results and engineering characteristics is ambiguous. Moreover, it is important that geotechnical engineers who need to work with these clays have background information on their engineering characteristics.
This thesis provides comprehensive information on the engineering characteristics and behaviour of sensitive marine clays in Ottawa. This information will give key information to geotechnical engineers who are working with these clays on their behaviour. For the purpose of this research, fifteen sites in the Ottawa area are taken into consideration. These sites included alternative technical data from cone and standard penetration tests, undisturbed samples, field vanes, and shear wave velocity measurements. Laboratory testing carried out for these sites has resulted in acquiring engineering parameters of the marine clay, such as preconsolidation pressure, overconsolidation ratio, compression and recompression indexes, secondary compression index, coefficient of consolidation, hydraulic conductivity, clay fraction, porewater chemistry, specific gravity, plasticity, moisture content, unit weight, void ratio, and porosity. This thesis also discusses other characteristics of sensitive marine clays in Ottawa, such as their activity, sensitivity, structure, interface shear behaviour, and origin and sedimentation.
Furthermore, for the purpose of increasing local experience with the use of cone and ball penetrometers in sensitive marine clays in Ottawa, three types of penetrometer tips are used in the Canadian Geotechnical Research Site No. 1 located in south-west Ottawa: 36 mm cone tip, and 40 mm and 113 mm ball tips. The differences in their response in sensitive marine clays will be discussed. The temperature effects on the penetrometer equipment are also studied. The differences in the effect of temperature on these tips are discussed. Correlations between the penetrometer results and engineering characteristics of Ottawa's clays are verified.
The applicability of correlations between the testing results and engineering characteristics of sensitive marine clays in Ottawa is also presented in this thesis. Two correlations from the Canadian Foundation Engineering Manual are examined. One of these correlations is between the N60 values from standard penetration testing and undrained shear strength. The other correlation is between the shear wave velocity measurement and site class. Temperature corrections are suggested and discussed for penetrometer equipment according to laboratory calibrations. The significance of the effects due to radical temperature changes in Canada and Ottawa is discussed.
Some of the main findings from this research are as follows.
• The Canadian Foundation Engineering Manual presents a correlation between standard penetration tests (SPTs) and the undrained shear strength of soils. This relationship may not be applicable to sensitive marine clays in Ottawa.
• Another correlation between the site class, shear wave velocity, and undrained shear strength is presented by this same manual which may not be applicable to sensitive marine clays in Ottawa.
• The rotation rate for field vane testing as recommended by ASTM D2573 is slow for sensitive marine clays in Ottawa.
• Correction factors applied to undrained shear strength from laboratory vane tests may not result in comparable values with the undrained shear strength obtained by using field vane tests.
• Loading schemes in consolidation or oedometer testing may affect the quality of the targeted results.
• Temperature corrections should be applied to penetrometer recordings to compensate for the drift in the results of these recordings due to temperature changes.
• The secondary compression index to compression index ratio presented in the literature may not be the value obtained from this research.
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Engineering Characteristics of Sensitive Marine Clays - Examples of Clays in Eastern CanadaNader, Athir January 2014 (has links)
Sensitive marine clay in Ottawa is a challenging soil for geotechnical engineers. This type of clay behaves differently than other soils in Canada or other parts of the world. They also have different engineering characteristic values in comparison to other clays. Cone penetration testing in sensitive marine clays is also different from that carried out in other soils. The misestimation of engineering characteristics from cone penetration testing can result. Temperature effects have been suspected as the reason for negative readings and erroneous estimations of engineering characteristics from cone penetration testing. Furthermore, the applicability of correlations between cone penetration test (CPT) results and engineering characteristics is ambiguous. Moreover, it is important that geotechnical engineers who need to work with these clays have background information on their engineering characteristics.
This thesis provides comprehensive information on the engineering characteristics and behaviour of sensitive marine clays in Ottawa. This information will give key information to geotechnical engineers who are working with these clays on their behaviour. For the purpose of this research, fifteen sites in the Ottawa area are taken into consideration. These sites included alternative technical data from cone and standard penetration tests, undisturbed samples, field vanes, and shear wave velocity measurements. Laboratory testing carried out for these sites has resulted in acquiring engineering parameters of the marine clay, such as preconsolidation pressure, overconsolidation ratio, compression and recompression indexes, secondary compression index, coefficient of consolidation, hydraulic conductivity, clay fraction, porewater chemistry, specific gravity, plasticity, moisture content, unit weight, void ratio, and porosity. This thesis also discusses other characteristics of sensitive marine clays in Ottawa, such as their activity, sensitivity, structure, interface shear behaviour, and origin and sedimentation.
Furthermore, for the purpose of increasing local experience with the use of cone and ball penetrometers in sensitive marine clays in Ottawa, three types of penetrometer tips are used in the Canadian Geotechnical Research Site No. 1 located in south-west Ottawa: 36 mm cone tip, and 40 mm and 113 mm ball tips. The differences in their response in sensitive marine clays will be discussed. The temperature effects on the penetrometer equipment are also studied. The differences in the effect of temperature on these tips are discussed. Correlations between the penetrometer results and engineering characteristics of Ottawa's clays are verified.
The applicability of correlations between the testing results and engineering characteristics of sensitive marine clays in Ottawa is also presented in this thesis. Two correlations from the Canadian Foundation Engineering Manual are examined. One of these correlations is between the N60 values from standard penetration testing and undrained shear strength. The other correlation is between the shear wave velocity measurement and site class. Temperature corrections are suggested and discussed for penetrometer equipment according to laboratory calibrations. The significance of the effects due to radical temperature changes in Canada and Ottawa is discussed.
Some of the main findings from this research are as follows.
• The Canadian Foundation Engineering Manual presents a correlation between standard penetration tests (SPTs) and the undrained shear strength of soils. This relationship may not be applicable to sensitive marine clays in Ottawa.
• Another correlation between the site class, shear wave velocity, and undrained shear strength is presented by this same manual which may not be applicable to sensitive marine clays in Ottawa.
• The rotation rate for field vane testing as recommended by ASTM D2573 is slow for sensitive marine clays in Ottawa.
• Correction factors applied to undrained shear strength from laboratory vane tests may not result in comparable values with the undrained shear strength obtained by using field vane tests.
• Loading schemes in consolidation or oedometer testing may affect the quality of the targeted results.
• Temperature corrections should be applied to penetrometer recordings to compensate for the drift in the results of these recordings due to temperature changes.
• The secondary compression index to compression index ratio presented in the literature may not be the value obtained from this research.
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