ATTRITION RATES OF SOIL-CEMENT SUBJECTED TO WATER JETS

Laboratory erosion tests were conducted on clement stabilized loess-derived alluvium and sand mixtures that had been subjected to 12 cycles of freeze-thaw activity. At a constant water velocity the erosion rate decreased with increasing time and followed a semi-log relationship: the specimens lost 54 percent to 97 percent of their total weight loss during the first 30 min of the 5-hour tests. The attrition rate decreased with increasing relative durability of the soil-cement. Although the results of these tests cannot be used to predict the behavior of this material in the field, the general time-loss behavior appears to be valid. The implications of this study that might be applied to field conditions are (a) soil-cement composed of loess-derived alluvium and sand mixtures will withstand high water velocities, (b) at a given flow rate the erosion rate will decrease rapidly, and (c) the soil-cement will reach a stable configuration relatively early in the flow event.