Utilizing Silkworm Cocoon Fibres for Improving Strength of Clay: An Experimental Study

Clayey soils are always associated with undesirable mechanical properties that limit their direct use as foundation materials without a particular treatment process. Many methods have been developed to improve the mechanical characteristics of the problematic clay soil. Using different types of fibre in ground improvement has generally approved a significant enhancement of the engineering properties of the soil. Silkworms are insects that produce cocoons enriched with durable silk fibres. Although these products are being used in valuable industrial sectors, the waste of such material can be used in alternative fields. This study aims to investigate the contribution of cocoon fibres to the strength and stiffness of kaolinite clay. For that purpose, cocoons have been cut into two different shapes of threads and mixed with a specific amount of clay and water to gain a desired predetermined density. The UCS test was performed on each specimen, and the results were analysed. The results showed that the inclusion of cocoon threads in clay samples has shown a significant improvement in the unconfined compression strength of the mixture. However, it reduces the initial elastic modulus of the soil.