Liquefaction is an important cause of damage to civil infrastructures during earthquakes. It is most likely to occur in fine to medium sands or even finer non-plastic soils. An increase of the percentage of plastic fines within the soil decreases the likelihood of rearrangement of soil particles during cyclic loading and reduces the potential for liquefaction. Treatment of a soil with bentonite increases the percentage of plastic fines, restrains the movements of the soil grains, and thus reduces the potential for liquefaction of the soil. As a result, the treated soil performs as a passive autoadaptive material where its properties are most useful when an unexpected and potentially catastrophic event occurs. In this project the following issues are investigated: (1) Changes in liquefaction potential of clean sands as a result of the addition of bentonite. (2) Corresponding changes in characteristic soil properties such as stiffness, strength, and hydraulic conductivity. (3) A novel means by which to deliver bentonite suspensions to the soil pores in time-release fashion in which the bentonite hydrates after it has been delivered.
