Mechanically stabilized earth (MSE) walls are widely used earth retention systems. MSE walls often contain galvanized steel strips as mechanical reinforcement between layers of specified backfill material. Inclusion of these strips creates a stronger composite material connected to a visually appealing wall facing; however, galvanized steel reinforcement is potentially vulnerable to corrosion. Corrosivity of MSE backfill may be characterized using electrical resistivity. Many designers currently use variations of the American Association of State Highway and Transportation Officials (AASHTO) standard T 288 to calculate resistivities of MSE backfill and require a minimum resistivity value for metal-reinforced backfill, typically 30 to 50 ohm-meters. A new procedure has been developed that appears to more accurately simulate field conditions. Material resistivities determined using this Proposed ASTM were up to two orders of magnitude higher than those determined for the same select materials using T 288 and matched well with field tests conducted by Kansas State University on the same compacted aggregate backfill.
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