In this paper

three different percentages of basalt fiber contents

i.e.0.2%

0.4%and 0.6% by weight were randomly mixed into expansive soil.Based on consolidated-undrained triaxial test

the characteristics of stress-strain relation and reinforcing effect under different confining pressures

different reinforced contents

were studied.The results show that the stressstrain curves of reinforced expansive soil possess strain hardening characteristic

the higher the confining pressure

the deviator stress of expansive soil reinforced with basalt fiber goes bigger and reinforcing effect becomes stronger.Under the same confining pressure

the deviator stress of reinforced expansive soil first increases and then decreases with the increase of fibers.The reinforcing effect coefficient is maximum in the 0.4%fiber contents

In addition

the internal friction angle of the reinforced expansive soil only changes a little under different reinforcing patterns

but the cohesion obviously increases.