Effect of different fiber combinations on density and unrestricted compressive strength of clay

Document Type : Research Article

Authors

1 Faculty of Civil Engineering, Islamic Azad University of Najafabad Branch, Isfahan, Iran

2 Department of Geology- University of Isfahan

Abstract

In recent years, a lot of research has been done on soil reinforced with different fibers. However, in most of these studies, one type of fiber has been used and less attention has been paid to the problems of combining different fibers. Also, the use of waste fibers has been less considered economically and environmentally. Therefore, in this study, the shear strength of clay has been investigated using 5 types of fibers including industrial steel, scrap steel, glass, polypropylene and straw, individually and in combination. The research process is that first, a control design is prepared from fiber-free soil. Then, soil samples were prepared with the mentioned fibers individually with the values ​​of 0.5, 0.75 and 1%. And in the third stage, samples of soil with fibers, in dual composition including: industrial steel and glass, industrial steel and polypropylene, glass and polypropylene, scrap steel and straw with weight percentages (0.25 and 0.75), (0.5 and 0.5) and (0.75 and 0.25), respectively. Finally, the maximum specific gravity and uniaxial compressive strength of all designs have been studied and compared. The results of this study showed that among the samples made with one type of fiber, glass with a value of 1%, the highest specific gravity and compressive strength, and among binary compounds, a combination of industrial steel and glass with a value of (0.75 0.25%), the highest specific gravity and with the amount (0.25 and 0.75%), the highest compressive strength is obtained.

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[1] F. Schlosser, P. Delage, Reinforced soil retaining structures and polymeric materials, in:  The Application of Polymeric Reinforcement in Soil Retaining Structures, Springer, (1988) 3-65.
[2] R. Kaushik, T. Sharma, Influence of waste polypropylene fibers on resilient modulus of clay soil, Int. J. Res. Advent Technol, 7(1) (2019) 251-255.
[3] M. Zaryoun, M. Hosseini, Lightweight fiber-reinforced clay as a sustainable material for disaster resilient architecture of future buildings, Architectural Engineering and Design Management, 15(6) (2019) 430-444.
[4] A. de Oliveira Júnior, J.F. Jucá, J. Ferreira, L. Guilherme, Geotechnical Behavior and Soil-Fiber Interaction of Clayey Soil Mixed with Randomly Dispersed Coconut Fibers, Soils and Rocks, 42 (2019) 127-138.
[5] Q. Cheng, J. Zhang, N. Zhou, Y. Guo, S. Pan, Experimental Study on Unconfined Compression Strength of Polypropylene Fiber Reinforced Composite Cemented Clay, Crystals, 10(4) (2020) 247.
[6] T. Sharma, R. Kaushik, Effect of Polypropylene Fiber on Properties of Bagasse Ash-Cement Stabilized Clay Soil, 10 (2019) 255-266.
[7] A. Saygılı, M. Dayan, Freeze-thaw behavior of lime stabilized clay reinforced with silica fume and synthetic fibers, Cold Regions Science and Technology, 161 (2019).
[8] M. Mirzababaei, A. Arulrajah, A. Soltani, N. Khayat, Stabilization of soft clay using short fibers and poly vinyl alcohol, Geotextiles and Geomembranes, 46 (2018).
[9] ASTM Standard D-4318, Standard Test Methods for Liquid Limit, Plastic Limit, and Plasticity Index of Soils, ASTM International, (2010).
[10] ASTM Standard C-127, Standard Test Method for Relative Density (Specific Gravity) and Absorption of Coarse Aggregate, ASTM International, (2001).
[11] ASTM D-854, Standard Test Methods for Specific Gravity of Soil Solids by Water Pycnometer, ASTM International, (2010).
[12] ASTM D-698, Standard Test Methods for Laboratory Compaction Characteristics of Soil Using Standard Effort (12 400 ft-lbf/ft3 (600 kN-m/m3)), ASTM International, (2012).
[13] ASTM D-2487, Standard Practice for Classification of Soils for Engineering Purposes (Unified Soil Classification System), ASTM International, (2011).
[14] ASTM Standard D-422, Standard Test Method for Particle-Size Analysis of Soils, ASTM International, (2007).
[15] ASTM D-2166, Standard Test Method for Unconfined Compressive Strength of Cohesive Soil, ASTM International, (2013).
[16] ASTM D-4767, Standard Test Method for Consolidated Undrained Triaxial Compression Test for Cohesive Soils, ASTM International, (2011).