Aiming at cost-effective use of cement-mixed gravel as the backfill of critical civil structures allowing small deformation, such as bridge abutments, a series of drained triaxial compression tests were performed on cement-mixed well-graded gravel. Based on these test results, new construction management standard for the cement-mixed gravel for the backfill of bridge abutment was prescirbed and it was applied to the current project of new bullet line at Kyushu. Additional large triaxial tests on core-sampled cement-mixed gravel specimen at Kyushu were also carried out and these specimens cleared the required strength, indicating that the standard is reasonable and practical.