Heterogeneous settlement is a common engineering problem in the soft soil foundation or at the juncture between new and old subgrade induced by consolidation settlement

rainfall or earthquake. The reinforced soil structure is commonly applied to reduce the unequal settlement in practices. However

less attention goes to theoretical research on the deformation of reinforcing material under differential settlement condition at present. To improve and simplify the design theory of reinforced earth structure

the deformation of reinforcement in reinforced soil structure is investigated based on the theory of parabolic cable. A method is developed to calculate reinforcement material deformation under differential settlement condition. The feasibility and accuracy of the proposed method are verified by laboratory experiment and theoretical analysis. The method does not require repeated numerical simulation. The calculation results can satisfy the needs of the actual project.