Abstract:

Inferior strength, which is caused by salt expansion, dissolution and water absorption of inshore saline soil, will be prevented with the help of reinforcement with wheat straw and lime. First, some samples are prepared, which including saline soil, reinforced saline soil with wheat straw, lime-saline soil, and reinforced saline soil with lime and wheat straw as the way of reinforcement in whole, upper and lower position respectively. Then, unconfined compressive strength tests of 50 mm, 152 mm (heavy compaction specimen) and 102 mm (lightly compaction specimen), as well as triaxial shear test of 61.8 mm in diameter are carried out. Finally, strength increment, ratio of deviator stress, and cohesion increment are defined to evaluate the reinforcement effect. The results show that: 1. Reinforcement raise the strength and the anti-deformation of soil. 2. Reinforced action increase largely the cohesion of soil, and the reinforcement in lower position can contribute a more effective role. 3. Strength of reinforced soil is contributed mostly by wheat straw and lime; the strength in water depends on chemical reaction of lime. 4. Lateral deformation of reinforced soil is restricted by means of wheat straw within a lower confining pressure, and that is supported jointly by reinforcement and confining pressure within a higher confining pressure. Reinforcement with wheat straw is one of the suitable means for improving strength and anti-deformation of inshore saline soil.

Key words: reinforced soil, compressive strength, shear strength, strength increment, stress-strain, wheat straw, inshore saline soil