Effects of Biomass Soil Mixture on Dynamic Behavior

Toyama Prefecture has a thriving fishing and forestry industry, which generates a large amount of waste biomass in the manufacturing process. The authors have considered if we could make effective use of these biomass instead of throwing it away. Specifically, the authors have considered if we could make effective use of snow crab shells and Moso bamboo as recycled materials. On the other hand, as large earthquakes often occur in Japan, it is necessary to investigate the dynamic behavior of the biomass-mixed soil under earthquake conditions before it can actually be used. Therefore, the authors carried out the cyclic undrained triaxial test on soil in this study using a mixture of 10 and 20% of these biomasses by mass in the soil as it was mixed. The results showed that adding bamboo and crab powder to the masa soil increased the liquefaction strength. However, the liquefaction strength decreased as the mixing ratio of biomass increased. The author also considered that the reason for the increase in liquefaction strength was due to the shape and skeleton of the biomass and made microscopic observations using a SEM. The results showed that the biomass contained a large number of large and small fibrous T-bamboos and crab shells with rough and sharp H-surfaces. This is thought to have increased the stickiness of the material and made it more difficult to liquefy.