A STUDY ON EROSION CONTROL USING JUTE GEOTEXTILES

Abstract

Erosion is the removal of top valuable fertile soil from the rivers, streams, seas; oceans, agricultural lands, canal banks, highway and railway embankments, etc. One of the most striking and intriguing features of erosion is their tendencies widen to from time to time. Erosion control is thus the technique that aims to prevent loss of material from bed and/or bank. Geotextiles serve as erosion control material in addition to other functions of separation, reinforcement, filtration and drainage. Jute geotextile is all effective erosion control material and has advantages over all other conventional techniques where vegetation is considered to be the long term answer to slope protection and erosion control. The work reported in this thesis is an experimental investigation concerning the study of erosion using non-uniform graded sand and clay material for preparation of the bed and bank of a one side bank channel flume with and without being covered by different types of jute geotexitiles. The main objective was to determine reliable erosion control mechanism by simple and inexpensive techniques involving the use of geofabrics. Experiments were performed in a one side vertical and other side banked channel; 3.4m long, 0.50m wide flume and having a constant side slopes of IV: 1.5H and IV: 1H. Non-uniform graded sediment of two different types viz. sand and clay, and five different specifications of woven jute geotextiles, viz. Type I, Type II, Type III, Type IV and Type V, and one rot resistance and bitumen treated jute viz. Type VI were used. The data were collected from steady flow conditions on the bed and sides of the channel. The steady state condition was identified only by visual observations on the bed and sides of the channel. In this study using single and combination of the following parameters i.e., shear stress distribution, velocity profile, Froude number, various longitudinal and bank slopes, if soil texture, etc, the extent and amount of eroded volume of the bed and bank on the experimental flume were observed. From the analysis of experimental data, it was found that the channel covered by thick thread, smaller mesh size, and heavy weight woven jute geotextile with bed and bank covered material non-uniform graded cohesive soil have a better erosion control performance over the others used in the experiment excepting the rot resistance and bitumen treated jute.