Advances in Volume Measurement in Unsaturated Soil Triaxial Tests

Laloui, Lyesse; Peron, Hervé; Geiser, F.; Rifa’i, Ahmad; Vulliet, L.

doi:10.3208/sandf.46.341

Cited by 41 publications

(18 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In contrast to the saturated case, for sample volume measurements under unsaturated conditions, both air and water exchanges contribute to the variation in soil specimen volume. Laloui et al (2006b) summarized commonly used methods for measuring volume changes in unsaturated soil specimens.…”

Section: Introductionmentioning

confidence: 99%

Experimental Investigations of Temperature and Suction Effects on Compressibility and Pre-Consolidation Pressure of a Sandy Silt

Salager

Baudin

Youssoufi

et al. 2008

Soils and Foundations

View full text Add to dashboard Cite

Section: Introductionmentioning

confidence: 99%

Experimental Investigations of Temperature and Suction Effects on Compressibility and Pre-Consolidation Pressure of a Sandy Silt

Salager

Baudin

Youssoufi

et al. 2008

Soils and Foundations

View full text Add to dashboard Cite

“…As with lasers, direct contact with the specimen is not required, and the soil profile is measured over its entire height. Laloui et al (2006) reported volume change measurements during shearing of unsaturated sandy silt at a constant suction of 100 kPa (the air-entry value of the tested soil was 80 kPa) using both mixed air/water controller and image processing techniques. Both techniques showed reasonably good agreement until the appearance of strain localization (at an axial strain of approximately 12%; Fig.…”

Section: Direct Measurements On the Specimenmentioning

confidence: 99%

“…Soil volume change cannot be computed purely on the basis of variation in water volume, nor can it be measured by using the same techniques used in conventional saturated soil testing. Several measurement techniques have been developed for unsaturated soil volume change, which can be classified in three broad categories (Laloui et al 2006):…”

Section: Volume Change Measurementsmentioning

confidence: 99%

Mechanical Testing in Unsaturated Soils

2008

Self Cite

View full text Add to dashboard Cite

The state-of-the-art report presented herein is aimed at documenting, to the largest extent possible, some of the recent advances in laboratory testing of unsaturated soils for stress-strain-strengthstiffness characterization under suction-controlled isotropic, axisymmetric, and true triaxial stress states. The report is intended to be neither comprehensive nor fully inclusive, offering plenty of room for further discussion on recent refinements and techniques not yet reported in the literature. The main sections in this report are devoted to describing current methods and technologies using cylindrical triaxial systems, including advances in volume change measurements; resonant column/torsional shear systems; bender element-based systems; and suction-controlled testing under true triaxial stress states. Concluding remarks are included in the last section of the report.

show abstract

“…The techniques of volume change measurement of unsaturated soils are well documented by Ng et al (2002), Laloui et al (2006), and Hoyos et al (2008). Generally, these techniques can be classified in three broad categories: (1) cell liquid measurement, of which the volume change of the specimen is measured indirectly by observing the liquid surrounding the specimen, such as the earlier work by Bishop and Donald (1961), the double-walled cell system (Wheeler 1988), and the double cell system with the open-ended inner cell (Cui and Delage 1996;Toyota et al 2001;Aversa and Nicotera 2002;Ng et al 2002); (2) direct air-volume and water-volume measurements, of which the measurement systems are connected to the pore air or pore water network directly and usually used in the drained test (Adams et al 1996;Laudahn et al 2005); and (3) direct measurement on the specimen locally by placing the contact or non-contact displacement transducers, such as Hall effect transducers, Wheatstone bridge circuit transducer, proximity transducer, laser transducer, etc.…”

Section: Introductionmentioning

confidence: 99%

A System to Measure Volume Change of Unsaturated Soils in Undrained Cyclic Triaxial Tests

Wang

Sato²,

Koseki

et al. 2016

Geotech. Test. J.

View full text Add to dashboard Cite

It is common to employ a traditional double cell system, of which an open-ended inner cell is installed in an ordinary triaxial apparatus, to measure the volume change of unsaturated specimens. In such a system, the total apparent volumetric strain of the specimen (e v ) is deduced from the water level change in the inner cell, monitored by a differential pressure transducer (DPT) considering, meanwhile, the top cap intrusion into the inner cell recorded by a vertical displacement transducer (VDT). Severe apparent volumetric strain, caused by the compliance of the double cell system (e v,SC ), was observed during the undrained cyclic loading tests in a previous study. Test results on a steel-spring dummy specimen revealed that e v,SC was induced not only by such as the meniscus effect, but unexpectedly also by the asynchronous responses between the DPT and the VDT (i.e., the response of the DPT was delayed compared with that of the VDT). By doing some treatment e v,SC could be reduced to some extent, whereas the magnitude of e v,SC was still too high to be acceptable when the tested specimen approached the liquefied state. To radically solve these technical difficulties, a modified double cell system, named the linkage double cell system, was developed in this study. In this modified system, a linkage rod moving simultaneously with the loading shaft was introduced, through which the DPT could directly measure e v without considering the top cap or loading shaft intrusion. Test results for the steel-spring dummy specimen as well as for saturated and unsaturated soil specimens demonstrated that the linkage double cell system has major advantages in measuring accurately the volume change of the specimen during undrained cyclic triaxial loading tests compared with the traditional double cell system. Keywords linkage double cell system, triaxial apparatus, unsaturated soil, volumetric strain, undrained cyclic loading test Manuscript

show abstract

Advances in Volume Measurement in Unsaturated Soil Triaxial Tests

Cited by 41 publications

References 23 publications

Experimental Investigations of Temperature and Suction Effects on Compressibility and Pre-Consolidation Pressure of a Sandy Silt

Experimental Investigations of Temperature and Suction Effects on Compressibility and Pre-Consolidation Pressure of a Sandy Silt

Mechanical Testing in Unsaturated Soils

A System to Measure Volume Change of Unsaturated Soils in Undrained Cyclic Triaxial Tests

Contact Info

Product

Resources

About