Showing papers in "Canadian Geotechnical Journal in 1974"
TL;DR: In this article, the stiffness and damping of footings and structures supported by piles can be predicted if dynamic stiffness is generated by the soil-pile interaction, and an approximate analytical approach is presented.
Abstract: Dynamic response of footings and structures supported by piles can be predicted if dynamic stiffness and damping generated by soil–pile interaction can be defined. An approximate analytical approac...
598 citations
TL;DR: In this paper, the bearing capacity of footings resting on subsoils consisting of two layers was investigated for the cases of dense sand on soft clay and loose sand on stiff clay.
Abstract: The ultimate bearing capacity of footings resting on subsoils consisting of two layers has been investigated for the cases of dense sand on soft clay and loose sand on stiff clay. The analyses of d...
245 citations
TL;DR: In this article, a review of the periglacial literature in the Mackenzie River valley between Fort Simpson and Fort Good Hope, N.W.T is presented, coupled with field exploration and study.
Abstract: As a result of recent field exploration and study in the Mackenzie River Valley between Fort Simpson and Fort Good Hope, N.W.T., coupled with a review of the periglacial literature it is evident th...
175 citations
TL;DR: In this article, the results of a field measurement program aimed at determining the ground movements created by the hand excavation of a 4.146m diameter shield-driven tunnel at a depth of 29.3m were presented.
Abstract: The paper describes the results of a field measurement program aimed at determining the ground movements created by the hand excavation of a 4.146 m diameter shield-driven tunnel at a depth of 29.3...
133 citations
TL;DR: The susceptibility of sensitive soils to large flowslides is a serious geotechnical problem Scientific study of this natural phenomenon is necessary if future losses of life and property are to be as discussed by the authors.
Abstract: The susceptibility of sensitive soils to large flowslides is a serious geotechnical problem Scientific study of this natural phenomenon is necessary if future losses of life and property are to be
99 citations
TL;DR: In this article, the improvement of weak or loose soil deposits by the vibrational technique has now become a well established method. Loose or medium dense sands can be compacted with slender, cylindrical vibrator.
Abstract: The improvement of weak or loose soil deposits by the vibrational technique has now become a well established method. Loose or medium dense sands can be compacted with slender, cylindrical vibrator...
96 citations
TL;DR: In this paper, the failure of a test embankment built on a soft, sensitive, and cemented clay in Saint-Alban, Quebec, was reported as a first stage of a research program.
Abstract: The present paper reports on the failure of a test embankment built on a soft, sensitive, and cemented clay in Saint-Alban, Quebec. The embankment was built as a first stage of a research program a...
77 citations
TL;DR: In this paper, a mathematical model of an expanding spherical cavity in a nonlinear viscoelastic-plastic medium with time, temperature, and normal pressure dependent strength properties is proposed to predict the creep settlement and bearing capacity of frozen soils under deep circular loads.
Abstract: The purpose of this paper is to develop a method for predicting the creep settlement and the bearing capacity of frozen soils under deep circular loads. The theory uses experimentally determined creep parameters of frozen soil and is intended to be applicable to the design of deep circular footings and screw anchors embedded in permafrost soils. On the basis of available experimental evidence, it was concluded that a mathematical model different from that usual in soil mechanics should be used in solving the time-dependent bearing capacity problem of such footings. The solution proposed in the paper was obtained by using the mathematical model of an expanding spherical cavity in a nonlinear viscoelastic-plastic medium with time, temperature, and normal pressure dependent strength properties. For a given footing or anchor, the theory furnishes either isochronous load-displacement curves, or load-creep rate curves, or a time-dependent bearing capacity for which formulas and graphs of nonlinear elastic-plast...
75 citations
TL;DR: In this article, a comparative study of the undrained creep rupture characteristics of a saturated, normally consolidated, undisturbed marine clay has been carried out under triaxial and plane strain conditions.
Abstract: A comparative study of the undrained creep rupture characteristics of a saturated, normally consolidated, undisturbed marine clay has been carried out under triaxial and plane strain conditions. Cr...
70 citations
TL;DR: A reticulate ice vein network is of common occurrence in many lake and marine clays, glacial tills, and mudflow deposits in permafrost areas of northern Canada as mentioned in this paper.
Abstract: A reticulate ice vein network is of common occurrence in many lake and marine clays, glacial tills, and mudflow deposits in permafrost areas of northern Canada. The ice vein network may grade downw...
53 citations
TL;DR: In this paper, a theoretical solution for the progress of consolidation of a saturated soil layer subjected to cyclic loading is obtained, and it is shown that consolidation, proceeding inwards from the drainage face, is slower than c...
Abstract: A theoretical solution for the progress of consolidation of a saturated soil layer subjected to cyclic loading is obtained.Consolidation, proceeding inwards from the drainage face, is slower than c...
TL;DR: In this paper, an apparatus has been devised for measuring the hydraulic conductivity of frozen soils, which involves the use of reservoirs, and it is shown that frozen soils contain a significant amount of water which moves under appropriate gradients.
Abstract: Frozen soils contain a significant amount of water which moves under appropriate gradients. An apparatus has been devised for measuring the hydraulic conductivity. It involves the use of reservoirs...
TL;DR: In this article, three full scale test fills were built on a soft Champlain clay deposit in Saint-Alban, Quebec, with different slopes of 1.24, 1.32, and 1.52.
Abstract: As part of an extensive field testing program, three full scale test fills were built on a soft Champlain clay deposit in Saint-Alban, Quebec.The fills were built to the same height of 11 ft (3.3 m) but with different slopes of 1.5/1, 2.5/1, and 4/1, and with resulting factors of safety of 1.24, 1.32, and 1.52. The foundations were heavily instrumented.From the observed construction behavior it was shown that the foundations behave elastically up to a critical height equal to 6, 8, and 9 ft (1.8, 2.4, and 2.7 m), respectively, or to about 50% of the failure height of each fill. Beyond this limit, local yielding of the clay occurred.The behavior in the elastic phase could be predicted adequately on the basis of CIU tests, provided Poisson's ratio be assigned a value of 0.3 instead of the usual 0.5. To obtain an adequate settlement prediction over the full range of heights, the finite element method could be used but a modified clay model should be developed which includes a yield criterion in addition to t...
TL;DR: A field study of landslides has shown that certain types of mass movement in the Mackenzie Valley, N.W.T. are associated with shear failure in frozen soil as mentioned in this paper.
Abstract: A field study of landslides has shown that certain types of mass movement in the Mackenzie Valley, N.W.T. are associated with shear failure in frozen soil. These land-slides have been classified on a descriptive basis as being block and multiple retrogressive slides. A detailed description of the characteristic morphology, and of the soil and permafrost conditions at these slides has been presented.Quantitative analysis of slides at a site on the Mountain River are consistent with the view that failure occurs through frozen soil with the base of the slide in unfrozen clay. It appears that high pore water pressures control the available shear strength in the unfrozen clay and that the long term strength of the permafrost soils is governed by a frictional resistance.
TL;DR: In this article, a series of thaw-consolidation tests on undisturbed frozen samples of Arctic soils is described, and the tests were carried out in a special oedometer, and thawing was induced by the application of a sudden constant increase in surface temperature.
Abstract: A series of thaw–consolidation tests on undisturbed frozen samples of Arctic soils is described. The tests were carried out in a special oedometer, and thawing was induced by the application of a sudden constant increase in surface temperature. Settlements, pore water pressures, and rates of thaw are measured, and interpreted in the light of current theories of heat transfer and thaw–consolidation. Excellent agreement is obtained between predicted and observed thaw rates, using published thermal properties. The observed pore pressures and settlements also are consistent with predicted behavior.These test results on a variety of undisturbed permafrost samples increase the level of confidence when applying the theory of consolidation for thawing soils to natural permafrost deposits.
TL;DR: In this article, a method for bearing capacity of footings on two layered soils with varying cohesion, friction, and unit weight based on the second theorem of Drucker and Prager (kinematical co...
Abstract: A method has been formulated for bearing capacity of footings on two layered soils with varying cohesion, friction, and unit weight based on the second theorem of Drucker and Prager (kinematical co...
TL;DR: In this article, a field study of uplift forces by frost heaving is described for columns of various types and sizes and for a block concrete wall, where the changing ground surface heave pattern around the block wall was used to predict the maximum heaving force which compared favorably with the measured value.
Abstract: Field studies of uplift forces by frost heaving are described for columns of various types and sizes and for a block concrete wall. The changing ground surface heave pattern around the block wall was used to predict the maximum heaving force which compared favorably with the measured value.Unit adfreeze strengths and maximum uplift forces were highest for steel columns, followed by concrete and wood; the lowest values were for the block concrete wall. In general, unit adfreeze strengths were highest for the small diameter columns and lowest on the largest columns. Differences are ascribed to the response of the various materials to air temperatures and to the shape and size of the structure.
TL;DR: In this article, detailed investigations have been made on the sites of two landslides which occurred in the sensitive Champlain clay deposits of the Saint-Laurent Lowlands of Canada.
Abstract: Detailed investigations have been made on the sites of two landslides which occurred in the sensitive Champlain clay deposits of the Saint-Laurent Lowlands. Laboratory tests made on specimens cut f...
TL;DR: In this article, a comparative study of both field and laboratory measurements of the geotechnical properties of a very dense glacial till was carried out to determine the feasibility of founding the major structures of a thermal generating station complex on very dense till.
Abstract: This paper presents the results of a comparative study of both field and laboratory measurements of the geotechnical properties of a very dense glacial till. This study was carried out to determine the feasibility of founding the major structures of a thermal generating station complex on very dense till. In situ pressuremeter tests, vertical and lateral plate load tests, and in situ shear box tests were carried out. A comparative laboratory test program on soil specimens from undisturbed block samples consisted of drained and undrained triaxial compression tests including a number of K0 and stress path tests. Foundation design parameters obtained from pressuremeter tests were in good agreement with the plate load test values. Laboratory test values underestimate the strength and deformation modulus of the dense till. The factors which influence the differences in the field and laboratory values of the strength and deformation properties of the till are discussed.
TL;DR: In this paper, the undrained shear strength and the fabric of a lacustrine clay from Winnipeg, Manitoba, have been determined with respect to the orientation of the natural bedding plane.
Abstract: The undrained shear strength and the fabric of a lacustrine clay from Winnipeg, Manitoba, have been determined with respect to the orientation of the natural bedding plane. Unconfined compression tests show that both the undrained shear strength and the normalized secant modulus of 'undisturbed' clay were anisotropic. The fabric, determined by X-ray diffraction analysis, was also found to be anisotropic in the 'undisturbed' samples. The same material in the remolded condition was isotropic with respect to both undrained shear strength and fabric. Observations of the failure plane have been used to calculate the resolved shear stress on the failure plane, and the results agree qualitatively with prediction, according to Jaeger's weak plane hypothesis. The variation of undrained shear strength with orientation may be due to (1) the clay fabric and (2) stratification, although these two factors may be interdependent.
TL;DR: In this article, a numerical stress solution which considers the difference between compressive and tensile moduli with respect to tensile strength, tensile stress-strain relationship, is developed, and the magnitude of errors associated with the incorrect assumption of equal modulus in tension and comp...
Abstract: Analysis and design of impermeable cores of earth dams against cracking require knowledge of the tensile strengths and tensile stress–strain relationships of the concerned soils. The same is needed for any stress and deformation analysis of an earth structure when a portion of it is expected to be in tension. In order to investigate behavior of soils in tension the Brazilian tensile test has been employed and found advantageous over other methods. However the interpretation of results of this test is involved because of the biaxial stress conditions existing at the center of the test specimen. Neglecting this fact leads to erroneous evaluation of the test results, particularly if the moduli in tension and compression differ. A numerical stress solution which considers the difference between compressive and tensile moduli with respect to tensile strength and tensile stress–strain relationship is developed. The magnitude of errors associated with the incorrect assumption of equal modulus in tension and comp...
TL;DR: In this paper, an experimental investigation of the anisotropic shear strength characteristics of the layered Lake Agassiz clays and the mechanism of failure for slopes in these layered clays were described.
Abstract: Two major aspects of an investigation dealing with the stability of natural and cut slopes in the Winnipeg area are described. The first concerns an experimental investigation of the anisotropic shear strength characteristics of the layered Lake Agassiz clays and the second is a study of the mechanism of failure for slopes in these layered clays.Four main types of clay were investigated and it was found that the effective shear strength parameters were greater for failure across the layers than for failure along the layers. Residual shear strength parameters were also determined.Stability analyses were carried out for representative slope cross sections using circular and noncircular failure surfaces, taking into account the anisotropic shear strength effects measured in the laboratory tests.Factors of safety were found for the conventional method of analysis assuming circular arc failure surfaces and isotropic shear strength properties. These factors of safety were found to be up to 0.5 greater than those obtained from noncircular failure surfaces which partially passed along the layers and so mobilized the lower shear strength properties of these layers. Deux aspects importants d'une etude de la stabilite des pentes naturelles et des talus d'excavation dans la region de Winnipeg sont presentes. Le premier concerne une etude experimentale des caracteristiques d'anisotropie de resistance au cisaillement des argiles stratifiees du Lac Agassiz, le second etant une analyse du mecanisme de rupture des talus dans ces argiles stratifiees.Quatre principaux types d'argile ont ete analyses et il a ete etabli que les parametres de resistance au cisaillement effective etaient plus importants dans une direction de cisaillement recoupant les strates que dans une direction parallele aux strates. Les parametres de resistance au cisaillement residuelle ont egalement ete determines.Des analyses de stabilite ont ete faites pour des sections de talus representatives, en utilisant des surfaces de rupture circulaires et non circulaires et en tenant compte de l'anisotropie de resistance au cisaillement observee lors des essais de laboratoire.Les facteurs de securite ont aussi et... Language: en
TL;DR: In this article, a stability analysis of road embankments based on a total stress concept is presented, and it is found that the minimum factor of safety obtained could give a too conservative picture of the actual conditions.
Abstract: Slides in soft marine clays frequently occur during construction of road embankments in Norway. This paper outlines the routine procedure used for a stability analysis of such embankments, based on a total stress concept. Using these procedures, eight slides were investigated, and it was found that the minimum factor of safety obtained could give a too conservative picture of the actual conditions. The minimum factor of safety, which is the one normally used, varied between 0.73 and 1.10. Taking all uncertainties into consideration, an analysis based on a total stress concept as outlined herein must be considered acceptable. The study gives no basis for evaluating the accuracy of the measured shear strength values.
TL;DR: In this paper, a method of stability analysis was developed to accommodate the distinctly nonlinear nature of the strength envelopes for Champlain Sea clays in the low stress range appropriate to stability problems.
Abstract: A method of stability analysis was developed to accommodate the distinctly nonlinear nature of the strength envelopes for Champlain Sea clays in the low stress range appropriate to stability proble...
TL;DR: In this article, the horizontal displacements measured at the toe of eight embankments were analyzed as a function of the factor of safety and the ratio of the thickness of the soft layer to the width of the embankment.
Abstract: The horizontal displacements measured at the toe of eight embankments are analyzed as a function of the factor of safety The embankments are built on layers of soft clay Only the undrained stage is studiedWhen the factor of safety of the embankments is higher than about 14, the horizontal displacements on the ground surface, at the toe of the embankment seem to follow an elastic law which is highly dependent on the ratio of the thickness of the soft layer to the width of the embankment When the factor of safety is lower than about 14, the horizontal displacements do not follow an elastic law, they increase considerably Consequently, it is suggested that the horizontal displacements be precisely measured at the toe of embankments during construction These measurements are simple and sensitive to the approach of failure, they can be efficiently used to control the stability of embankments This study also gives some information concerning the variation of horizontal displacements versus depth
TL;DR: In this paper, the bearing capacity theory, design, site selection, construction and testing of the ice bridges spanning the main rivers was discussed, and a winter road crossing eight rivers was built in the James Bay territory to enable the installation of camps and the mobilization of all equipment, materials and fuel needed for the construction of a permanent road leading to the La Grande River.
Abstract: In 1972 and 1973, a winter road crossing eight rivers was built in the James Bay territory to enable the installation of camps and the mobilization of all equipment, materials and fuel needed for the construction of a permanent road leading to the La Grande River. This paper reports on the bearing capacity theory, design, site selection, construction and testing of the ice bridges spanning the main rivers.
TL;DR: In contrast to tundras, where the mass of vegetation is relatively small, boreal forest vegetation exerts a more important buffering effect on energy flux to and from the ground surface as discussed by the authors.
Abstract: In contrast to tundras, where the mass of vegetation is low and its effect on energy exchange relatively small, boreal forest vegetation exerts a more important buffering effect on energy flux to and from the ground surface. Air movement below the canopy is reduced, and a relatively high proportion of solar radiation is absorbed by the canopy directly, to be lost as sensible or latent heat. Removal of the buffer provided by stratified vegetation results in increased soil heat flux and ground temperatures, and increased depth of the active layer, which in areas of ice rich permafrost can lead to surface subsidence.
TL;DR: In this paper, a comparison of theoretical Fourier amplitude spectra of strong ground motion (FS) with the corresponding spectras of real earthquake accelerograms is performed to elucidate the physical processes of seismic events.
Abstract: A comparison of theoretical Fourier amplitude spectra of strong ground motion (FS) with the corresponding spectra of real earthquake accelerograms is useful in elucidating the physical processes th...
TL;DR: A test program was conducted in northern Manitoba to evaluate the creep behavior and load capacity of 8-, 10-, and 15-in. screw anchors embedded in permafrost (frozen, stratified silts and clays containing ice at about 31.5 °F (−0.3 °C).
Abstract: A test program was conducted in northern Manitoba to evaluate the creep behavior and load capacity of 8-, 10-, and 15-in. (20.3-, 25.4-, and 38.1-cm) diameter power-installed screw anchors embedded in permafrost (frozen, stratified silts and clays containing ice at about 31.5 °F (−0.3 °C)). The test results show that the anchors behaved under uplift loads, in a manner that was essentially very similar to that exhibited by deep footings of the same size. No failure planes (slip surfaces) were observed around the plates but a deformed zone above the plates was clearly visible in the varved soil when the anchors were excavated after testing. A method of analysis which allows the test data to be used directly for design, based on secondary creep rates and allowable displacements, is described.
TL;DR: Significant advances in understanding Pleistocene stratigraphy have provided a new framework for geotechnical investigations in southern Saskatchewan as mentioned in this paper, and it can now be demonstrated that these problems are fundamentally related to the Plascoidean stratigraphic columns.
Abstract: Significant advances in understanding Pleistocene stratigraphy have provided a new framework for geotechnical investigations in southern Saskatchewan. In Saskatchewan, three formal stratigraphic groups have been recognized in the Pleistocene based on the concept of multiple glaciation. The engineering significance of this stratigraphic framework has now been established.Some of the geotechnical problems in Saskatchewan, related to Pleistocene deposits include slope instability, problems associated with groundwater, location of gravel aggregates, and excavating and handling embankment materials. It can now be demonstrated that these problems are fundamentally related to Pleistocene stratigraphy. Examples are included to illustrate this approach.The analysis of these deposits requires special criteria to establish the true stratigraphic column in terms of reference sections. It has been shown that the reference sections can be extended over very large areas of the region. The principal investigation techniq...