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

Document Type : Research Article


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

2 Department of Geology- University of Isfahan


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.


Main Subjects

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