抄録
The use of randomly distributed fibre as a reinforcement medium for cement-treated soil has been receiving some attention in recent years. Studies have shown this to be an efficient method to control and improve the brittle behavior of cement-treated soil. However, the fibres may be non-uniformly distributed over the mixture. This issue with non-uniform fibre concentration or difficulties with fibre mixing could be significant in the field, and it may affect the overall behavior of the treated soil mass. This paper presents a laboratory study on fibre distribution effect on behavior of fibre-reinforced cement-treated Singapore marine clay. The fibre distribution analysis will be conducted with randomly selected samples while the behaviour will be investigated mainly through unconfined compression test. Polypropylene (PP) fibres with 6 to 12mm cut length and 0.25% to 2.0% fibre content (by weight) will be mixed with high cement-admixed clay. The results show that for 6mm long PP fibres reinforced mixture, fibre distribution shows higher non-uniformity when fibre content is lower(0.5%) or higher(2.0%), which results in higher variability in peak strength and ductility. This non-uniform fibre distribution has more significant effect on ductility than on peak strength. Corresponding density analysis indicates very minor fibre distribution effect. For 12mm long PP fibres reinforced mixture, the high non-uniform fibre distribution due to lower or higher fibre content seems to be more significant. However, the fibre distribution effect on strength and ductility looks quite similar to 6mm long PP fibres reinforced specimens.
