Open Access Open Access  Restricted Access Subscription or Fee Access

A Laboratory Study on the Influence of Anisotropy on the Soil Behavior

Mohammed A. Al-Neami(1*)

(1) Civil Engineering Departemnt, Univesity of Technology, Iraq
(*) Corresponding author



Anisotropy refers to any directional-dependence on material property. In recent years, the anisotropy of intermediate-strain behavior and shear strength, small-strain stiffness anisotropy has attracted attention. The main aim of this paper is to clarify the influence of inherent anisotropy on the compressibility characteristics and shear strength behavior of fine-grained soils. A special manufactured device has been made in order to prepare and collect the samples in different directions. Then, a series of conventional tests have been carried out on the soil samples consists of unconfined compressive and Oedometer tests. Low plasticity clay has been used with three liquidity indices (0.22, 0.32, and 0.44) in order to achieve the goal of the study. The results have showed that the anisotropy had an impact on the undrained shear strength of cohesive soil and the soil strength can be considered as strength anisotropy. The higher anisotropy angle causes the more reduction in the shear strength. The settlement is affected by anisotropy, increasing of the anisotropy leads to the increase of the settlement, the compression and the swelling indices. The coefficient of consolidation in the vertical direction is lower than the coefficient in inclined direction and the ratio of (ch/cv) tends to increase with anisotropy angle the highest ratio is 1.4.
Copyright © 2020 Praise Worthy Prize - All rights reserved.


Anisotropy; Orientation Angle; Shear Strength; Compressibility; Sampling

Full Text:



S. Nishimura, Laboratory Study on Anisotropy of Natural London Clay, Ph.D. thesis, University of London, 2005.

W. H. Ward, S. G. Samuels and N.E. Butler, Further studies of the properties of London clay. Geotechnique Vol. 9, No. 2, pp.33-58, 1959.

P.W Mayne, Stress Anisotropy Effects on Clay Strength, Journal of Geotechnical Engineering. ASCE. 111(3), 1985.

C. Zarei, H.S. Jigheh, and Z. Badv, Effect of Inherent Anisotropy on the Behavior of Fine-Grained Cohesive Soils. International Journal of Civil Engineering, 2018.

J. Chai, T. Negami, K. Aiga, and T. Hino., Effect of pore water chemistry on anisotropic behavior of clayey soil and possible application in underground construction. Underground Space. Vol. 1, Issue 2, pp. 114-123, 2016.

A Laskar and S. K. Pal, Investigation of the Effects of Anisotropic Flow of Pore Water and Multilayered Soils on Three-Dimensional Consolidation Characteristics, Advances in Materials Science and Engineering, volume 2017.

K. Ueda, K. Uratani and S. Lai, Influence of inherent anisotropy on the seismic behavior of liquefiable sandy level ground. Soils and Foundations, Vol. 59, Issue 2, pp 458-473, 2019.

Q. Huang Jin, F. Zou and Z. Qian, Face stability analysis for a longitudinally inclined tunnel in anisotropic cohesive soils. Journal of Central South University. Vol. 26, Issue 7, pp 1780–179, 2019.

K. B. Agarwal, The Influence of Size and Orientation of Sample on the Undrained Strength of London Clay, Ph.D. thesis. Imperial College of Science and Technology, University of London, 1968.

H. Ohta and A. Nishihara, Anisotropy of Undrained Shear Strength of Clay under Axi-Symmetric Loading Conditions, Soil and Foundations, Japanese Geotechnical Society of Soil Mechanics and Foundation Engineering. Vol. 25, No. 2, pp. 73-86, 1986.

L. C. Kurukulasuriya, M. Oda and H. Kazama, Anisotropy of Undrained Shear Strength of an Over-Consolidated Soil by Triaxial and Plane Strain Tests. Soil and Foundations, Japanese Geotechnical Society. Vol. 39, No. 1, Pp 21-29, 1999.

S. F. Su and H. J. Liao, Effect of Strength Anisotropy on Undrained Slope Stability in Clay, Géotechnique, Vol. 49, Issue 2, pp. 215-230, 1999.

H. Toyota, A. Susami and S. Takada, Anisotropy of Undrained Shear Strength Induced by K0 Consolidation and Swelling in Cohesive Soils, International Journal of Geomechanics, vol. 14, Issues 4, 2014.

M. Goudarzy, D. König, JC. Santamarina, T. Schanz The influence of the anisotropic stress state on the intermediate strain properties of granular material. Géotechnique: 1–12. p.180. 2017.

A. H. J. Al-Rkaby, A. Chegenizadeh, H. R. Nikraz, Directional dependence in the mechanical characteristics of sand: a review, Int. J. Geotech. Eng., vol. 10, no. 5, pp.499-509, 2016.

K. Senetakis and H. Li, Influence of stress anisotropy on small-strain stiffness of reinforced sand with polypropylene fibres. Soils and Foundations. Vol. 57 pp. 1076–1082, 2017.

L.T. Yang, X. Li, H.S. Yu, and D. Wanatowski, A laboratory study of anisotropic geomaterials incorporating recent micromechanical understanding. Acta Geotech. 11 (5), pp. 1111–1129. 2016.

A. H. J. Al-Rkaby, A. Chegenizadeh, H. R. Nikraz, Anisotropic Shear Strength of Sand Containing Plastic Fine Materials. World Academy of Science, Engineering and Technology International Journal of Geotechnical and Geological Engineering, Vol:11, No:3, 2017.

Mohammed A. Al-Neami, Falah H. Rahil & Khaldoon S. Al-Bayati (2016) Bearing capacity of batter piles embedded in sandy soil, International Journal of Geotechnical Engineering, 10:5, 529-532.

G. Wrzesinski, K. Pawluk, M. Lendo-Siwicka, and A. Miszkowska, Undrained shear strength anisotropy of cohesive soils caused by the principal stress rotation. IOP Conference Series: Materials Science and Engineering, 2019.

P. Pakdel, J. Reza and M. Veiskarami, An estimate of the bearing capacity of shallow foundations on anisotropic soil by limit equilibrium and soft computing technique. Geomechanics and Geoengineering. Vol. 14, - Issue 3, pp.202-2017, 2019.

Y. Liu, D. Zhang, X. Wang, P. Yu and W. Hua, Anisotropic Strength of Granular Material Considering Fabric Evolution, Latin American Journal of Solids and Structures, Vol. 16 (3), e174. 2019.

J. Freeland Soil Anisotropy: Mechanisms and Hydrologic Consequences. 2013. Published by American Geophysical Union an Earth and space science blog network 2019.

M. A. Al-Neami, F.H. Rahil and K.S. Al-Bayati, A Laboratory Driving System to Simulate the Insertion of Piles Models with Various Angles, Patent No.5334, the IPC E02D7/08. 2016.

M. A. Al-Neami, Investigation of Sampling Error on Soil Testing Results. International Journal of Civil Engineering and Technology, 6(7), pp. 44-52. 2018.

B. Farhadi and A. Lashkari, Influence of soil inherent anisotropy on behavior of crushed sand-steel interfaces, Soils and Foundations. Vol. 57, pp. 111–125, 2017.

B.C. O’Kelly, Consolidation anisotropy of some natural soft soils. Proceedings of International Conference on Problematic Soils, Cyprus, Vol. 3, pp. 1183 – 1192. 2005.

R. Jia, Consolidation behavior of Ariake clay under constant rate of strain, Ph.D. Saga University, Japan 2010.

Shestopalov, A., Boitsev, A., Methods for Evaluation Structural Anisotropy of Asphalt, (2017) International Review of Mechanical Engineering (IREME), 11 (5), pp. 361-364.

Al-Sultan, A., Al-Wakel, S., Al-Taie, A., Experimental Study of Heavy Metal Dispersion through Cohesionless Soil: a Case Study of Cd+, (2019) International Review of Civil Engineering (IRECE), 10 (6), pp. 288-293.


  • There are currently no refbacks.

Please send any question about this web site to
Copyright © 2005-2022 Praise Worthy Prize