Multistage Consolidated Drained Triaxial Behavior of Shallow Landslide-Prone Soils in Rangamati Sadar, Bangladesh: Implications for Slope Stability and Critical State Analysis
DOI:
https://doi.org/10.64862/Keywords:
Triaxial test, Landslide, Critical stateAbstract
Shallow landslides are a common geo-hazard in the hilly regions of southeastern Bangladesh, particularly in Rangamati Sadar, where slope instability poses significant risks to infrastructure and human settlements. This study investigates the Multistage Consolidated Drained Triaxial behavior of normally consolidated clay and silty sandy soils obtained from shallow landslide-prone zones. A series of drained triaxial tests were conducted under varying effective confining pressures to evaluate stress-strain response, volume change, and critical state behavior. Results reveal stress strengthening characteristics, with maximum deviator stress occurring between 2.6% and 15% axial strain, followed by strain softening or stabilization. The soils exhibited contractive behavior during shearing, stabilizing near peak stress. Shear strength parameters were determined, with cohesion (c′) of 23.3 kPa and friction angle (ϕ′) of 30°. Critical State Soil Mechanics (CSSM) parameters—λ = 0.396, Γ = 1.84, and M = 0.044—were estimated, although a well-defined single Critical State Line (CSL) could not be established. These findings contribute to the understanding of soil behavior under drained loading conditions and provide valuable input for slope stability analysis and geotechnical design in landslide-prone areas.
References
Allman, M. A., and Atkinson, J. H. (1992). Mechanical properties of reconstituted Bothkennar soil. Géotechnique, 42 (2), 289–301. https://doi.org/10.1680/geot.1992.42.2.289
Craig, R. F. (2004). Craig’s soil mechanics (7th ed.). CRC Press.
Goodman, R. E. (1974). Methods of geological engineering in discontinuous rocks. West Publishing Company.
Ho, D. Y. F., and Fredlund, D. G. (1982). A multistage triaxial test for unsaturated soils. Geotechnical Testing Journal, 5 (1–2), 18–25. https://doi.org/10.1520/GTJ10795J
Hossain, A. T. M. S. (2001). The engineering behaviour of the tropical clay soils of Dhaka, Bangladesh (Doctoral dissertation, Durham University). https://etheses.dur.ac.uk/3959/
Houston, S. L., Perez-Garcia, N., and Houston, W. N. (2008). Shear strength and shear-induced volume change behavior of unsaturated soils from a triaxial test program, Journal of geotechnical and geoenvironmental engineering, 134 (11), 1619-163. https://doi.org/10.1061/(ASCE)1090-0241(2008)134:11(1619)
Khatun, M., Hossain, A. T. M. S., and Sayem, H. (2023). Multistage triaxial behavior of shallow landslide hazard site soil of Rangamati Sadar area, Bangladesh. Engineering, 15 (10), 581–595. https://doi.org/10.4236/eng.2023.1510041
Kovári, K., and Tisa, A. (1975). Multiple failure state and strain controlled triaxial tests. Rock Mechanics, 7 (1), 17–33. https://doi.org/10.1007/BF01239232
Mishra, B., and Verma, P. (2015). Uniaxial and triaxial single and multistage creep tests on coal-measure shale rocks. International Journal of Coal Geology, 137, 55–65. https://doi.org/10.1016/j.coal.2014.11.005
Nambiar, M. R. M., Venkatappa Rao, G., and Gulhati, S. K. (1985). Multistage triaxial testing: A rational procedure. In R. C. Chaney and K. R. DeMars (Eds.), Strength testing of marine sediments: Laboratory and in-situ measurements (ASTM STP 883, pp. 274–293). ASTM International. https://doi.org/10.1520/STP36340S
Parker, J. C., Amos, D. F., and Sture, S. (1980). Measurement of swelling, hydraulic conductivity, and shear strength in a multistage triaxial test. Soil Science Society of America Journal, 44 (6), 1133–1138. https://doi.org/10.2136/sssaj1980.03615995004400060002x
Taylor, D. W. (1951). A triaxial shear test investigation on a partially saturated soil. Massachusetts Institute of Technology, Soil Mechanics Laboratory Report.
Youn, H., and Tonon, F. (2010). Multi-stage triaxial test on brittle rock. International Journal of Rock Mechanics and Mining Sciences, 47 (4), 678–684. https://doi.org/10.1016/j.ijrmms.2009.12.017
Downloads
Published
Data Availability Statement
Department of Geological Sciences
Issue
Section
License
Copyright (c) 2025 Nepal Society of Engineering Geology (NSEG)
This work is licensed under a Creative Commons Attribution 4.0 International License.
