Influence of fine‐grained content on strength characteristics of Sabo soil‐cement



Sabo soil‐cement utilization is a construction method that constructs and reinforces Sabo structures. A strength of Sabo soil‐cement is affected by a synergism obtained from compaction of the soil and induration of Sabo soil‐cement by hydration reaction in case of INSEM method. At this time, the soil indurates under conditions where a cement hydrate spread throughout the soil, and especially, the amount of cement is proportional to the compressive strength. If the cement hydrate cannot spread all over the soil, `the indurating space’ and `the un‐indurating space’ arise in the soil. Herein, the strength properties of Sabo soil‐cement gradually turn from strength properties of Sabo soil‐cement to strength properties of cement by an increase of a unit cement amount. Then, we investigated the change of the strength properties, using a consolidated‐drained triaxial compression test on soils. It based on a change between the adhesive force of Sabo soil‐cement and the change of strength properties. The more amount of fine fraction increases, the more cement hydrates cannot spread all over the soil. The peak value of compressive strength is not clear despite fine‐grained fraction content when the cement is less than50kg/m3. The fine‐grained fraction content of soil reduced less than20%to appear strength of the Sabo soil‐cement. In addition, Sabo soil‐cement mixes the cement amount fewer, and the shear resistance angle increase. On the other hand, Sabo soil‐cement mixes the cement amount more, and the shear resistance angle decrease conversely. Lastly, the fracture morphology of the soil‐cement test‐piece gets to barrel fracture which swells the center about strength properties of soil, and comes to cleavage like lengthwise crack or slanting shear fracture like concrete.

Key words

Sabo soil‐cement, Strength properties, Minimum management strength, Uniaxial compression test, Triaxial compression test