Assessment of Retaining Wall Inventories for Geotechnical Asset Management

With federal transportation funding legislation for asset management, state departments of transportation are expanding the scope of assets included in their transportation asset management plans. Retaining walls represent a significant portion of the overall assets in an agency's transportation corridor system. However, under the conventional approach, significant human resources and time are required to develop retaining wall inventories from physical condition surveys and to follow a bridge inspection program for management of retaining walls. The proposed alternative to physical inventory and condition assessment for managing systemwide retaining wall assets is based on asset density in specified subsets of the transportation corridors. Systemwide retaining wall assets are estimated from corridor subsets with similar wall densities per unit length of the corridor. Then, the systemwide condition of retaining wall assets is evaluated with a deterioration function based on age (i.e., life expectancy) of the asset. The resulting conclusions provide program managers with a tool for predicting systemwide needs for maintenance, rehabilitation, and replacement. The proposed alternative offers the flexibility of integrating physical inventories and condition assessments with time, as well as incorporating improved asset deterioration functions or forecast curves.