Evaluating the Moisture Content Variation on Critical Strain of Geo-materials: A Case Study


  • Dlshad Khurshid Khailany Department of Civil Engineering Cihan University Erbil, Kurdistan Region, Iraq
  • Mohammed M. Saleh Department of Civil Engineering College of Engineering Universita Della Calabria Casenza, Italy
  • Ako Daraei Department of Civil Engineering Faculty of Engineering Soran University Soran Kurdistan Region, Iraq




The tunnel’s stability during construction is a very important matter. Some methods have been proposed for stability evaluation, but the hazard warning levels (HWLs) are more applicable among these methods. Despite monitoring and applying HWLs, several collapses in Shibli twin tunnels in Iran have cast doubts on the accuracy of this criterion in the presence of water. In this study, the critical strains under different water contents were measured through uniaxial compressive strength tests on 11 different shale and marl samples. A comparison of laboratory tests and numerical results shows that the influence of the moisture content on the critical strain is negligible. In addition, the results show that there is no direct relationship between the critical strain and uniaxial compression strength.


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How to Cite

Al-Khailany, D. K., Mohammed M. Saleh and Daraei, A. . (2022) “Evaluating the Moisture Content Variation on Critical Strain of Geo-materials: A Case Study”, Journal of Engineering, 28(6), pp. 27–38. doi: 10.31026/j.eng.2022.06.03.