The strength law of coir fiber-reinforced soil based on modified Duncan-Chang model

A large diameter triaxial sample of 61.9 mm was made by adding coir fiber into red clay. The range confining pressure 50–200 kPa; content 0.1%–0.4%; and length 10–40 mm. By varying the pressure, length, unconsolidated undrained tests were used to study shear strength variation law fiber-reinforced soil. experimental data processed establish a linear model segmental elastic modulus, analysis determine fitting parameters improve Duncan-Chang combining concept damage ratio. modified fits stress-strain relationship coir-reinforced results show clear dividing line for effect on samples, which is about 30 0.3%, respectively. At same time, can fit soil reflect curve characteristics