ADHESION AT JUTE GEOTEXTILE : CLAY SLURRY INTERFACE

Abstract

In the use of jute fabric for the layered clay-jute geotextile-sand method for land reclamation, it is important to determine the interface behavior between the jute geotextile and various clay types commonly found in dredged seabed soils. Since jute is used to separate and support thin sand seams to form a horizontal drainage layer on top of a soft clay slurry, the interface behavior between the jute and the slurry must be examined. The adhesion on the interface between the jute and the clay slurry is measured using the incremental penetration of a suspended endweighted jute sheet under an incremental load into a prepared clay slurry with various moisture contents, in order to obtain the interface stress value under a quasi-static condition. The effects of sheet width and sheet type were investigated earlier, and found to have a negligible effect on the interface adhesion for the water content range tested. In order to examine the effects of clay-type, several mixtures of Kaolin-Bentonite in fixed proportions were prepared to produce clays of liquid limits ranging from 100% to 400%. The interface adhesion between the jute and four samples of Kaolin-Bentonite mixes at various water contents from two to six times the liquid limits were measured using the vertical sheet test. These mixes included clay types with liquid limits from 100% to 400%, thus allowing the nature of jute/slurry interaction to be studied for a wide range of clay type. When the water contents are normalized by the liquid limits, it was observed that the interface adhesion values fall into a very narrow behaviour band, thus making it possible to estimate the available interface strength between jute and clay slurry based on water contents.