The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform
Anh Minh Tang - One of the best experts on this subject based on the ideXlab platform.
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Macro-microscopic one-dimensional compression of wet granular soils by experimental investigation
E3S Web of Conferences, 2016Co-Authors: Vinh-du Than, Jean Noël Roux, Jean-michel Pereira, Patrick Aimedieu, Michel Bornert, Anh Minh TangAbstract:The presence of liquid menisci between soil particles in wet granular soils plays a key role in the macroscopic behavior. This liquid bridge between particles may also allow the existence of metastable microstructures that lead to mechanical instabilities when the soil in subjected to external loadings. In this work, the authors present an investigation into macroscopic and microscopic behaviors of wet granular soils in very loose state under one-dimensional (1D) compression by using Oedometer Test combined with the X-ray computed tomography (X-ray CT) observations. The specimen is prepared in the presence of a small amount of a water meniscus by using the controlled pluviation method. The influences of various mechanical parameters are first studied on the compression curve. The microstructure along those compression curves are then analyzed by using X-ray CT to observe the arrangement of microstructure under growing of applied force.
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Macro-microscopic one-dimensional compression of wet granular soils by experimental investigation
The 3rd European Conference on Unsaturated Soils, 2016Co-Authors: Vinh-du Than, Jean Noël Roux, Jean-michel Pereira, Patrick Aimedieu, Michel Bornert, Anh Minh TangAbstract:© 2016 The Authors. The presence of liquid menisci between soil particles in wet granular soils plays a key role in the macroscopic behavior. This liquid bridge between particles may also allow the existence of metastable microstructures that lead to mechanical instabilities when the soil in subjected to external loadings. In this work, the authors present an investigation into macroscopic and microscopic behaviors of wet granular soils in very loose state under one-dimensional (1D) compression by using Oedometer Test combined with the X-ray computed tomography (X-ray CT) observations. The specimen is prepared in the presence of a small amount of a water meniscus by using the controlled pluviation method. The influences of various mechanical parameters are first studied on the compression curve. The microstructure along those compression curves are then analyzed by using X-ray CT to observe the arrangement of microstructure under growing of applied force.
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anisotropy in Oedometer Test on natural boom clay
2015Co-Authors: Anh Minh Tang, Pierre Delage, Xiangling Li, Xavier SillenAbstract:The mechanical behaviour of Boom Clay has been studied for many years in the context of geological disposal of radioactive waste in Belgium. The aim of this study is to investigate the anisotropic behaviour of Boom Clay in terms of compressibility and hydraulic conductivity. Oedometer Tests (with effective vertical stress (\( \sigma_{v}^{{\prime }} \)) up to 32 MPa) were carried out on samples of various orientations: parallel, perpendicular and inclined 45° to the bedding plane. The compressibility index (C c ) and swelling index (C s ) were compared. Only a slight difference between these parameters was observed, suggesting that the anisotropic behaviour of Boom Clay cannot be revealed under the Test conditions adopted. The hydraulic conductivity (k) was also determined by the Casagrande’s method for different values of vertical effective stress (\( \sigma_{v}^{{\prime }} \)). Unlike compressibility, the hydraulic conductivity, however, showed a clear anisotropic behaviour with k ver < k inc < k hor .
Vinh-du Than - One of the best experts on this subject based on the ideXlab platform.
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Macro-microscopic one-dimensional compression of wet granular soils by experimental investigation
E3S Web of Conferences, 2016Co-Authors: Vinh-du Than, Jean Noël Roux, Jean-michel Pereira, Patrick Aimedieu, Michel Bornert, Anh Minh TangAbstract:The presence of liquid menisci between soil particles in wet granular soils plays a key role in the macroscopic behavior. This liquid bridge between particles may also allow the existence of metastable microstructures that lead to mechanical instabilities when the soil in subjected to external loadings. In this work, the authors present an investigation into macroscopic and microscopic behaviors of wet granular soils in very loose state under one-dimensional (1D) compression by using Oedometer Test combined with the X-ray computed tomography (X-ray CT) observations. The specimen is prepared in the presence of a small amount of a water meniscus by using the controlled pluviation method. The influences of various mechanical parameters are first studied on the compression curve. The microstructure along those compression curves are then analyzed by using X-ray CT to observe the arrangement of microstructure under growing of applied force.
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Macro-microscopic one-dimensional compression of wet granular soils by experimental investigation
The 3rd European Conference on Unsaturated Soils, 2016Co-Authors: Vinh-du Than, Jean Noël Roux, Jean-michel Pereira, Patrick Aimedieu, Michel Bornert, Anh Minh TangAbstract:© 2016 The Authors. The presence of liquid menisci between soil particles in wet granular soils plays a key role in the macroscopic behavior. This liquid bridge between particles may also allow the existence of metastable microstructures that lead to mechanical instabilities when the soil in subjected to external loadings. In this work, the authors present an investigation into macroscopic and microscopic behaviors of wet granular soils in very loose state under one-dimensional (1D) compression by using Oedometer Test combined with the X-ray computed tomography (X-ray CT) observations. The specimen is prepared in the presence of a small amount of a water meniscus by using the controlled pluviation method. The influences of various mechanical parameters are first studied on the compression curve. The microstructure along those compression curves are then analyzed by using X-ray CT to observe the arrangement of microstructure under growing of applied force.
Khairul Anuar Kassim - One of the best experts on this subject based on the ideXlab platform.
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Criteria of Acceptance for Constant Rate of Strain Consolidation Test for Tropical Cohesive Soil
Geotechnical and Geological Engineering, 2016Co-Authors: Khairul Anuar Kassim, Ahmad Safuan A. Rashid, Ahmad Beng Hong Kueh, Lam Chee SiangAbstract:In this study, the rapid consolidation equipment (RACE) was developed as an alternative device to the conventional consolidation Test using Oedometer, consuming merely a few hours for the whole precedure to determine the consolidation characteristics of cohesive soil. RACE operates based on the constant rate of strain (CRS) consolidation theory, which is a continuous loading method of Testing, requiring a good estimation of the loading rate such that it is ideal for the achievement of steady state condition during Testing. The steady state condition is achieved when the c _ v values from drained and undrained face of CRS converged with the c_v from Oedometer Test. A slightly modification has been made on the normal constant rate of strain (CRS) Test by proposing a direct back pressure system to the specimen using a tube to saturate the soil sample. This research has produced a set of criteria for determining the suitable rate for the rapid consolidation Test based on the ratio of normalized strain rate, β , and proposed a new coefficient in terms of a ratio of β to clay fraction (CF), as a part of new criteria for Testing a fine soil. Four types of sample were Tested with different rates of strain using the RACE and their results were compared with those conducted using the Oedometer on the same soil type, from which fairly good agreements were evident in many specimens. It was found from the study that the minimum value of normalized strain rate, β , for the CRS Test is 0.005 and for the u _ a / σ_ v ratio is suggested as 0.01. Also, the maximum β /CF for soils with clay friction lower and higher than 50 % are 0.008 and 0.001, respectively. The minimum β /CF value for both conditions is 0.0001.
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consolidation characteristics of lime stabilised soil
Malaysian Journal of Civil Engineering, 2000Co-Authors: Khairul Anuar Kassim, Shiao Huey ChowAbstract:Soft clay is always associated with settlement and consolidation. Stabilisation of soft clay with lime as bearing stratum is an alternative to replacement of that material. The compression and consolidation characteristics of the stabilised material need to be fully understood for design purposes. This paper presents the results of study on the consolidation characteristics in terms of compressibility, rate of consolidation and the permeability characteristics of both unstabilised and lime stabilised soil samples using Oedometer Test. Oedometer specimens of 50 mm diameter and 20 mm height were Tested with respect to age at 0,7, 14 and 28 days and effective stress at 0, 200, 400, 800 and 1600 kPa. Three soil types were selected and studied in this project; they are Tapah Kaolin, Sungai Buloh clay and UTM clay. From the Test results, it is discovered that lime stabilisation improved the consolidation characteristics and reduced the settlement of unstabilised clay with age especially after stabilisation phase is achieved, i.e., after the age of 14 days.
Lam Chee Siang - One of the best experts on this subject based on the ideXlab platform.
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Criteria of Acceptance for Constant Rate of Strain Consolidation Test for Tropical Cohesive Soil
Geotechnical and Geological Engineering, 2016Co-Authors: Khairul Anuar Kassim, Ahmad Safuan A. Rashid, Ahmad Beng Hong Kueh, Lam Chee SiangAbstract:In this study, the rapid consolidation equipment (RACE) was developed as an alternative device to the conventional consolidation Test using Oedometer, consuming merely a few hours for the whole precedure to determine the consolidation characteristics of cohesive soil. RACE operates based on the constant rate of strain (CRS) consolidation theory, which is a continuous loading method of Testing, requiring a good estimation of the loading rate such that it is ideal for the achievement of steady state condition during Testing. The steady state condition is achieved when the c _ v values from drained and undrained face of CRS converged with the c_v from Oedometer Test. A slightly modification has been made on the normal constant rate of strain (CRS) Test by proposing a direct back pressure system to the specimen using a tube to saturate the soil sample. This research has produced a set of criteria for determining the suitable rate for the rapid consolidation Test based on the ratio of normalized strain rate, β , and proposed a new coefficient in terms of a ratio of β to clay fraction (CF), as a part of new criteria for Testing a fine soil. Four types of sample were Tested with different rates of strain using the RACE and their results were compared with those conducted using the Oedometer on the same soil type, from which fairly good agreements were evident in many specimens. It was found from the study that the minimum value of normalized strain rate, β , for the CRS Test is 0.005 and for the u _ a / σ_ v ratio is suggested as 0.01. Also, the maximum β /CF for soils with clay friction lower and higher than 50 % are 0.008 and 0.001, respectively. The minimum β /CF value for both conditions is 0.0001.
Shigeki Yoshitake - One of the best experts on this subject based on the ideXlab platform.
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interpretation of Oedometer Test data for natural clays
Soils and Foundations, 1995Co-Authors: Katsutada Onitsuka, Zhenshun Hong, Yutaka Hara, Shigeki YoshitakeAbstract:ABSTRACT Two alternative approaches to the conventional e—log p method for determining yield stress are critically examined in this paper, and their advantages and limitations are identified. The yield stresses defined in both alternative approaches are also theoretically verified as identical for the Oedometer Test data. A comparison of the advantages and limitations of both alternative approaches suggests that the In (1 + e)-log p approach should be used to interpret the Oedometer Test data for natural clays, and the defined yield stress can be interpreted as being responsible for the critical state of structure collapse. Systematic analyses on the Oedometer Test data for undisturbed Ariake clays and Shimabara clay demonstrate that it is valid to use the In (1 + e) – log p approach for determining the yield stress and both the compression and swelling indices of natural clays. In addition, some analysis implications are also given for useful parameters, such as, the critical-state pore pressure parameter in predicting the undrained strength of overconsolidated clays and the compression index ratio in evaluating the aging effect of natural clays. Finally, Nagaraj’s sample disturbance degree concept based on Oedometer Test data is extended to take into account both the effects of stress release and mechanical disturbance. The analysis results indicate that the defined degree of sample disturbance can reflect the combined extent of stress release and mechanical disturbance during sampling and handling.
