Measurement of Pressure Distribution on Roadbed Using Soil Bags During Plate Loading Tests

When constructing temporary roads for disaster recovery, it is necessary to improve the ground or replace the soil with high-quality soil when the ground conditions at the site are not good. However, it may be difficult to procure and transport a sufficient quantity of high-quality soil for replacement at some sites. In addition, when using cement to improve the ground, for example, the high strength of the ground can be maintained for a long period of time, but disadvantages are also encountered with its use. A ground improved by the addition of cement cannot be restored to its original condition. Moreover, cement is relatively expensive and has a negative impact on the environment. The use of soil bags, known as “do-nou” in Japan, is one of the effective methods for constructing temporary roads. The advantages of soil bags are that the strength of the ground can be improved more easily and quickly without the need for heavy machinery or modification by cement, and that the damaged areas can be repaired by replacing damaged soil bags with new soil bags. Thus, a roadbed can be simply removed and rapidly restored to its original condition. The loading characteristics of soil bags arranged as a stacked structure need to be understood. In the present study, in order to evaluate the loading characteristics of soil bags, cyclic plate-loading tests were conducted to investigate the pressure transfer among the soil bags and from the soil bags to the lower roadbed layer. It was found from the experiments that the earth pressure was distributed over a wider area in the structure with the staggered stacking of the soil bags than in the structure with the flat stacking of the soil bags.