Compaction, Hydraulic, and Consolidation Characteristics of Reinforced Clays with Carpet Waste

Document Type : Research Paper


1 Faculty of Civil Engineering, Sahand University of Technology, Tabriz, Iran

2 Ph.D. Candidate, Department of Civil Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran


Due to the importance of environmental issues and reducing energy consumption, the use of waste materials to improve the engineering properties of soils has been widely noticed by researchers in recent years. This research investigates the effect of carpet waste fibers on the compaction, hydraulic, and consolidation properties of kaolinite clay. Standard compaction, falling head permeability, and one-dimensional consolidation tests were performed on soil samples containing 0.5, 1, and 2 percent of fibers (relative to the dry weight of the soil). In order to investigate the effect of the fiber length on the results, the length of the fibers was changed from 6 to 30 mm. The results showed that the presence of carpet waste fibers decreases the maximum dry density and increases the optimal moisture content of the samples. Also, the carpet fibers increased the hydraulic conductivity of the samples and reduced the settlement of clay soil and its swelling index. So that the compression index and swelling index for the sample with 2% fibers with a length of 30 mm decreased by 35 and 64%, respectively. The presence of carpet fibers in the soil increases the speed of clay consolidation. From the obtained results, it was found that the changes in the consolidation properties of clay are more significant with the content of fibers compared to the length of the fibers.


Main Subjects

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