California Bearing Ratio of a Cohesive Soil Reinforced with Waste Tyre Fibres

Abstract

This paper investigates the influence of waste tyre fibres on the geotechnical properties of clayey soil used as a subgrade material. Laboratory California bearing ratio (CBR) tests were conducted for the unsoaked condition as a measurement of pavement performance under the normal rainfall. Three types of tyre fibres as TFA, TFB and TFC used in the present study were mixed in a proportion of 0.25, 0.5, 0.75 and 1% by dry mass of clayey soil. In each test, the specimen was prepared in accordance with the compaction characteristics achieved from the modified compaction energy. The test results reported that the compaction characteristics of cohesive soil were getting increased with an increase in fibre content. In general, regardless of the fibre size, the CBR values get increased with an increase in fibre content. The experimental results showed that clayey soil achieves five times higher CBR value for the addition of 0.75% TFC. From the test results, it can be concluded that the use of waste tyre fibres considerably reduces the pavement thickness and hence reduces the construction cost.