FALLING HEAD TEST FOR GEOTEXTILE DRAINAGE CAPACITY

Abstract

One of the leading causes of roadway degradation in the world is contamination of the aggregate base which results in strength loss. Thus, it will decrease the effective aggregate thickness destroying the road support and reducing roadway performance. Authorities and practitioners have found out that using geotextile in road construction can overcome the problems. However, there are a few tests must be done before the geotextile can be approved by the responsible party for use in road construction. One kind of the test is permittivity test. This paper presents an analysis of developing a prototype of falling head test for geotextile drainage capacity (permittivity) according to ASTM standard D4491-99. The tests were carried out in order to ensure all the parts of the apparatus can work smoothly and can give the accurate output data. The type of geotextile used in this analysis is a non-woven geotextile. The test was performed using different number of the layers and finally the head. The permittivity value obtained from this apparatus satisfies the standard values of permittivity of the materials tested.