Development of Physics-Based Deterioration Models for Reinforced Soil Retaining Structures

Since its emergence in the 1960s, soil reinforcement has become an indispensable technology providing solutions to earth retention in the US and globally. Reinforced soil retaining walls (also known as Mechanically Stabilized Earth walls or MSE walls) have quickly gained a reputation for being cost-saving, time-efficient, environmental-friendly, and resilient to seismic events, outperforming their conventional counterparts. In current practice, reinforced soil walls represent the substantial majority of all retaining walls constructed in transportation projects. However, none of the reinforced soil walls constructed thus far has yet proven to stand the test of time. The first reinforced soil wall in the US was constructed in California in 1972, which makes it 25 years younger than the 75-year service life expectancy. Further, design guidelines and construction materials and protocols have evolved significantly since the technology was first adopted in the 1970s. That is, the early walls were constructed using design guidelines and construction protocols that are deemed inadequate according to the current state of practice. Some of these early structures have recently failed unexpectedly as a result of their deterioration over time.

This project aims to develop, for the first time, physics-based deterioration models for reinforced soil walls. These deterioration models will serve as quantitative tools that will significantly enhance how transportation infrastructure stakeholders manage their aging reinforced soil retaining wall assets. The specific objectives of the project include:

• developing element-scale deterioration models for reinforced soil wall components,
• developing asset-scale deterioration models for reinforced soil walls, and
• developing asset-scale performance models that can be readily used by infrastructure stakeholders to manage their reinforced soil wall assets.