Load Development in Soil Nails from a Strain-Gauge Instrumented Wall

This paper contains analyses of an instrumented temporary soil nail wall in which strain-gauged nails were installed and monitored during and after construction. Three test sections were installed consisting of a total of 43 strain gauges on 10 soil nails and monitored for a total of nearly 6 months. The maximum stresses measured in the monitoring were significantly less than those predicted by the limit equilibrium design process used to analyze the walls. Loads continued to increase in the nails until the end of the monitoring program without any observable decrease in stress-accumulation rate. These observed mechanisms have far-reaching impacts on the design of temporary and permanent soil nail walls and should be further investigated with additional instrumentation.