This standard provides guidelines for the design and analysis of reinforced soil structures, such as retaining walls and embankments. It outlines the principles for ensuring both external stability (sliding, overturning, bearing capacity) and internal stability (reinforcement rupture, pullout).
Provides general guidelines for the design of reinforced soil structures.
Quick Reference Values
Min. Factor of Safety against Sliding (Static)1.5
Min. Factor of Safety against Overturning (Static)2.0
Min. Factor of Safety against Bearing Capacity (Static)2.5
Min. Factor of Safety against Reinforcement Rupture1.5
Min. Factor of Safety against Reinforcement Pullout1.5
Max. allowable percentage of fines in backfill< 15% passing 75 micron sieve
Key Formulas
Ti = Ka * σv * Sv — Maximum tension per unit width of wall in a reinforcement layer
Le = (Ti * FS_p) / (2 * σv * C_i * tan(φ'_fill)) — Required effective pullout length behind failure plane
Practical Notes
Drainage is critical for the long-term performance of reinforced soil walls; proper drainage systems behind and at the base of the wall must be included as per Clause 10.
The selection of backfill material is as important as the reinforcement. It must be granular and free-draining to prevent pore pressure buildup and ensure predictable soil-reinforcement interaction.
The interaction coefficient (Ci or F*) between soil and reinforcement is a key design parameter. If not reliably provided by the manufacturer, it should be determined from project-specific laboratory tests like pullout tests.