NEW EARTH REINFORCEMENT METHOD BY SOILBAGS ("DONOW")

HAJIME MATSUOKA and SIHONG LIU 

ABSTRACT: This paper presents a new earth reinforcement method by soilbags ("Donow" in Japanese) and its applications to such earth reinforcements as the reinforcement for a ballast foundations under railway sleeper, reinforcement for soft building foundations and the construction of retaining walls. The strength properties of soilbags are studied theoretically and verified through the biaxial compression tests on 2D model soilbags and the unconfined compression tests on real soilbags with various kinds of materials contained. It is found that the high strength of the soilbag is produced due to the tensile force of the bag when the soilbag is subjected to an external force and the bag expands. This reinforcing mechanism contains a "reversal idea" of making use of an external force, which is the "enemy" against the foundation. The earth reinforcement using soilbags has the advantages of improving greatly the bearing capacity for soft ground, resisting flexibly against deformation and being friendly to our environment with less noise during construction and no use of any chemical agents. It also has the effect of reducing traffic- or machine-induced vibration and preventing frost heave. 

Key words: bearing capacity, "Donow", frost heave, reinforcement, retaining wall, soft foundation, soilbag, vibration (IGC: K14)