The behaviour of a fibre-reinforced cemented soil

Triaxial compression tests with internal measurement of deformation and scanning electron microscopy were carried out to evaluate the effect of randomly distributed glass fibre reinforcement and cement content on the response of a sandy soil to load. Cemented specimens were prepared with cement contents varying from 0 to 5% by weight of dry soil and cured for 7 days. The fibre length was 12·8 mm, varying in a content from 0 to 3% by weight of dry soil. The cementation itself notably increased in stiffness and peak strength, while fibre inclusion increased both residual and peak strength and reduced stiffness, changing the behaviour of the cemented soil from brittle to more ductile. Peak strength envelopes indicated that the friction angle was increased from 35 to 41° as a result of cementation and 46° as a consequence of fibre inclusion. However, the peak cohesion intercept was unchanged after fibre addition, being a function only of cementation.