EXPERIENCES WITH MECHANICALLY STABILIZED STRUCTURES AND NATIVE SOIL BACKFILL

Practices and experience with mechanically stabilized backfill retaining structures typically using native soil backfill on low and moderate standard rural roads by the U.S. Department of Agriculture, Forest Service, are documented. Information is provided describing innovative and low-cost alternative earth-reinforced retaining structures, including welded wire walls, chainlink fencing walls, geotextile walls, and walls faced with materials such as timbers, tires, hay bales, geocells, and concrete blocks. The design process has involved either generic or custom in-house designs, or proprietary designs with custom site adaptation and materials evaluation. Local, often marginal-quality backfill material is typically used. Its use is discussed, along with advantages and problems with marginal materials. Selected case histories with various wall types and backfill materials are presented.