Three chemical stabilization methods--sulfate resistant cement (Type V), low-calcium fly-ash (Class F) mixed with sulfate resistant cement (Type V), and ground granulated blast furnace slag--were used in a series of repeated load triaxial tests on clayey soil to assess the effectiveness of these three stabilizers in enhancing resilient modulus (M sub R) properties of the soil. M sub R results were measured from repeated load triaxial tests conducted on both control and treated soils at optimum moisture content levels. Test results were analyzed to understand the potentials of each stabilizer on M sub R response of the soils and to study the effects of confining and deviatoric stresses on resilient response of the treated soils. Mechanisms for M sub R enhancements in treated soils were developed, and a series of flexible pavement design exercises was conducted to evaluate the impact of each stabilizer on the design thickness of the asphalt surface layer of pavements.