Consolidated drained behaviour of PVA fibre reinforced cemented Toyoura Sand

ABSTRACT

In this study, a series of consolidated drained (CID) compression tests were performed On unreinforced and reinforced cemented Toyoura sand specimens. Specimens were cured for 3, 7, 14, 28, 56 days, with cement contents of 0–3% (dry weight), and different Polyvinyl alcohol (PVA) fibre contents of 0, 0.5, 1, 2, and 3% (weight ratio). Samples were prepared to a target dry density value (e.g. ${\rho }_d$ = 1.489 g/cm³) of Toyoura sand using under-compaction moist tamping technique with 10% water content by dry weight of soil. Triaxial compression tests (CID) were carried out at a confining pressure of 100 kPa. The monotonic stress–strain, stiffness, volumetric change behaviour, dilatancy angle, peak strength, and residual strength and brittleness index of the samples were investigated in greater detail. Results show that peak strength increases due to increase in curing duration by approximately 50–700%, and 0–300% in residual strength at 30% axial strain, compared to Toyoura sand. For reinforced cemented specimens there is an increase in volumetric strain with increasing curing duration or in other words, the rate of dilation increases with the increase in curing period. The dilatancy behaviour increases due to the addition of fibres and cement, this dilative behaviour has been attributed to cemented particles forming highly interlocked clusters. Brittleness of the cemented specimens reinforced with 0.5%-1% fibres have been supressed significantly compared to the higher concentrations of fibre (2–3%). Hence, it shows that there might be a threshold fibre concentration range (0.5%-1%), where fibres are considered to be the most effective and beyond this concentration, fibre causes further adverse effects.

KEYWORDS:

• Fibre reinforced sand
• cemented sand
• triaxial test
• curing duration
• stress-strain

Acknowledgments

The research project was financially supported by the Western Graduate Research Scholarship at the Department of Civil and Environmental Engineering, Western University, London, Ontario, Canada. The authors would also like to acknowledge the Department of Civil Engineering, Fukuoka University, Fukuoka, Japan for providing Toyoura Sand and cement for the current research project.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data Availability Statement

The data that support the findings of this study are available from the corresponding author, upon reasonable request.

Additional information

Notes on contributors

Muhammad Safdar

Dr. Muhammad Safdar is a freelance geotechnical and educational consultant, currently working as an Assistant Professor at the Earthquake Engineering Center (EEC), Department of Civil Engineering (CED), UET Peshawar, Pakistan. Dr. Safdar completed his PhD in Geotechnical Engineering from Western University, London, Ontario, Canada. He also worked as a Research Associate at the School of Civil and Environmental Engineering, NTU, Singapore. He completed his master degree in Geotechnical Engineering from Pusan National University, Busan, South Korea and completed his Bachelor's in Civil Engineering from UET Peshawar, Pakistan.

Tim Newson

Dr. Tim Newson is a member of the Canadian Geotechnical Society and now the Vice-President North America for the ISSMGE from 2017 to 2021. Dr. Newson received his undergraduate degree in Civil and Structural Engineering (1988) and PhD in Geotechnical Engineering (1992) from the University of Wales, Cardiff, which is one of the premier civil engineering departments in the United Kingdom. Dr. Newson is currently a faculty member in the Department of Civil and Environmental Engineering and Research Director of the Geotechnical Research Centre of the University of Western Ontario. Dr. Newson interests have become quite varied and made contributions in soft soil and clay engineering, offshore and energy geotechnics, buried structures and foundations, geotechnical physical modelling (1g & centrifuge), static and dynamic laboratory testing of soil and constitutive modelling of soils and structures, leading to more than 150 technical papers in peer reviewed international conferences and journals.

Colin Schmidt

Colin Schmidt is an experienced geotechnical engineer focused on trenchless installations using horizontal directional drilling (HDD), auger boring, pipe ramming, and microtunnelling at Thurber Engineering, Ltd., Calgary, Alberta, Canada. He has managed scope, budget, schedule, and quality for a wide variety of geotechnical and environmental projects including site investigations, retaining wall and foundation installations, and environmental site assessments. He received his bachelors and masters degrees from Western University, London, Ontario, Canada.

Kenichi Sato

Dr. SATO Kenichi is affiliated to Civil Engineering, Fukuoka University, Japan, where Dr. SATO Kenichi is currently working as Professor. Dr. SATO Ken-ichi has authored and co-authored several national and international publications and also working as a reviewer for reputed professional journals. Dr. SATO Kenichi is having an active association with different societies and academies around the world. Dr. SATO Kenichi made his mark in the scientific community with the contributions and widely recognition from honourable subject experts around the world. Dr. SATO Ken-ichi has received several awards for the contributions to the scientific community. Dr. SATO Kenichi major research interest involves Geotechnical engineering, Geo-environmental engineering, Road engineering, Pavement engineering and Gor-waste engineering.

Takuro Fujikawa

Dr. FUJIKAWA Takuro is affiliated to Civil Engineering, Fukuoka University, Japan, where Dr. FUJIKAWA Takuro is currently working as Professor. Dr. FUJIKAWA Takuro has authored and co-authored several national and international publications and also working as a reviewer for reputed professional journals. Dr. FUJIKAWA Takuro is having an active association with different societies and academies around the world. Dr. FUJIKAWA Takuro made his mark in the scientific community with the contributions and widely recognition from honourable subject experts around the world. Dr. FUJIKAWA Takuro has received several awards for the contributions to the scientific community. Dr. FUJIKAWA Takuro major research interest involves Soil Foundations Engineering and Geo-environmental Engineering.