How do mechanically stabilized earth (MSE) walls work?

MSE walls use horizontal reinforcement (steel strips, geogrids, geotextiles) placed in compacted fill behind a facing. Reinforcement develops friction/interlock with soil, creating a stable composite mass. Design checks: internal stability (reinforcement pullout and breakage), external stability (sliding, overturning, bearing capacity, global stability), and facing connection capacity. Advantages: flexibility tolerates settlement, rapid construction, cost-effective for large heights, aesthetically versatile. Used for bridge abutments, retaining walls, and slopes.