Abstrait

Strength and Stiffness Response of Itanagar Soil Reinforced With Arecanut Fiber

T.Muni, Y. Jeram, K. Padu, Omo Yachang1, H.P. Singh

Natural fibers like coir, sisal, jute, cotton and others have attracted the attention of various researchers for applications in civil engineering works because they are cheap, locally available, biodegradable, eco-friendly and their inclusion significantly increases the engineering properties of soil. Among all the natural fibers Arecanut fiber appears to be one of the promising fiber because it is inexpensive, available in abundant and it is a very high potential perennial crop. India is in the top position in Arecanut production in world with its share of 55 percent. Keeping this in view the present study was taken up. In this study a series of triaxial compression tests under different confining pressures were conducted on locally available (Itanagar, Arunachal Pradesh, India) soil without and with Arecanut Fiber. The percentage of Arecanut fiber by dry weight of soil was taken as 0.25 %, 0.5 %, 0.75 and 1 % and they were randomly mixed with the soil. The soil samples of unreinforced and reinforced soil for triaxial tests were prepared at maximum dry density corresponding to optimum water content The shear strength parameters (c and 􀔄) and stiffness modulus (ϭd /􀔖 i.e. ratio of deviator stress to corresponding strain) of soil corresponding to each fiber content was determined. The effect of change in length of fiber was also investigated. Tests results indicate that on inclusion of Arecanut fiber, the shear strength parameters (c and 􀔄) and stiffness modulus (ϭd /􀔖) of soil increases. It was also observed that on increasing the percentage of Arecanut fiber, these parameters further increases and this increase is substantial at fiber contents of 1 %. It was further observed that the increase in length of fiber increases the shear strength parameters of reinforced soil. Thus there is a significant increase in shear strength parameters and stiffness modulus of soil due to addition of Arecanut fiber and this will considerably increase the load carrying capacity and reduce the value of immediate settlement of soil significantly.