The Use of High-Capacity Tensiometer for Cyclic Triaxial Testing of Railway Formation Material

Kumar, Ashutosh; Azizi, Arash; Toll, David G.

Abstract

The formation layers of railway embankments are often unsaturated and subjected to coupled cyclic traffic-induced and hydraulic loading. Understanding this coupled response requires the development of a testing protocol capable of subjecting soil samples to cyclic loading while continuously monitoring water retention response of the soil. An accurate measurement of the suction variation for the case of repeated cyclic loading is crucial for interpreting the response of the soil considering the principles of unsaturated soil mechanics that are commonly neglected during the design of this infrastructure. In this paper, we present the use of a high-capacity tensiometer of capacity 2 MPa and resolution 0.5 kPa developed at Durham University, capable of measuring suction on the body of soil samples. The setup allowed continuous monitoring of suction at the mid-height of the unsaturated soil sample during cyclic triaxial testing while continuously measuring the volumetric deformations with the help of local displacement transducers. The obtained results indicated that the volumetric compression during cyclic loading reduced the voids ratio leading to an increase in the degree of saturation under constant water content conditions that reduced the soil suction. The obtained results were then interpreted by using mean Bishop’s stress where the permanent strain was consistently found to increase with an increase in the Bishop’s stress ratio. The resilient modulus was also found to be correlated to Bishop’s stress ratio.

Citation

Kumar, A., Azizi, A., & Toll, D. G. (2024, November). The Use of High-Capacity Tensiometer for Cyclic Triaxial Testing of Railway Formation Material. Presented at 5th International Conference on Transportation Geotechnics (ICTG) 2024, Sydney, Australia

• Presentation Conference Type: Conference Paper (published)
• Conference Name: 5th International Conference on Transportation Geotechnics (ICTG) 2024
• Start Date: Nov 20, 2024
• End Date: Nov 22, 2024
• Acceptance Date: Apr 23, 2024
• Online Publication Date: Oct 22, 2024
• Publication Date: 2025
• Deposit Date: Oct 22, 2024
• Publicly Available Date: Oct 24, 2024
• Publisher: Springer
• Peer Reviewed: Peer Reviewed
• Volume: 1
• Pages: 307-315
• Series Title: Lecture Notes in Civil Engineering
• Series ISSN: 2366-2557
• Book Title: Proceedings of the 5th International Conference on Transportation Geotechnics (ICTG) 2024, Volume 1
• ISBN: 9789819782123; 9789819782130
• DOI: https://doi.org/10.1007/978-981-97-8213-0_33
• Public URL: https://durham-repository.worktribe.com/output/2979078