Field monitoring and numerical modeling of 4.4 m-high mechanically stabilized earth wall

A full-scale mechanically stabilized earth (MSE) wall was constructed and monitored in a residential compound in New Cairo, Egypt. The height of the wall was 4.4 m and the facing consisted of modular concrete blocks. The wall was reinforced with high-density polyethylene geogrid. This paper presents the instrumentation program and interpretation of measurements recorded at end of construction and after applying loads on top of the wall. Strains in the geogrid layers were measured using strain gauges. Deformations of the wall face were surveyed using a total station device. Backfill soil properties and geogrid stiffness properties were characterized through laboratory testing. A two-dimensional finite element model was developed to simulate the performance of the instrumented wall at end of construction. Reinforcement loads deduced from measured strains were compared to different load prediction methods: AASHTO Simplified, K-stiffness, Simplified stiffness, and finite element modeling. The paper highlights important aspects to be considered in numerical modeling of MSE walls. Predicted horizontal wall displacements and reinforcement loads from finite element modeling compared well to field measurements. The Simplified stiffness method better predicted the reinforcement loads compared to the AASHTO Simplified and K-stiffness methods.