袋詰めエアミルクの性能と道路路盤材料としての適用性

抄録

It is often being used for construction works such as backfill, void packing and widening of embankment because the foamed cement milk (FCM) consisting of cement, water and air bubble is a lighter and more fluid material. On one hand, the geotextile which has function to strengthen earth structure with a tensile resisting force of fiber has been employed in the reinforcing construction of banking and reinforced soil wall method from the past. In the present study, we have devised a material combining these advantages namely the geotextile-made bag (hereinafter referred to as “FCM bag”) which was filled with FCM, and have ascertained its efficiency as pavement materials by examining the bending strength of square column specimen and the elastic modulus of slab sized to actual execution.
According to result obtained from the laboratory test, both bending strength and deformation before reaching a failure of FCM bag tended to become larger than those of specimen without bag. This is considered to be the effect of adhesion between solidified FCM and an inner side of bag on increase of a tensile stress due to bending occurring in specimen. Secondly, we carried out the non-destructive bearing capacity test by dropping a weight as to the slablike FCM bags (a length of 5m, a width of 2m and thickness of 0.15 to 0.2m) which were laid on improved ground and conventional ground. Having executed the inverse analysis with measurement records following the site investigation, it was found that the elastic moduli of FCM bags were equal to or greater than those of about 0.5m thick stabilized layers. Moreover, the output consequences of the structural calculations of asphalt pavement using multi-layer elasticity theory indicated that the appropriating of FCM bag to subbase course brought a reduction in thickness of pavement, providing elastic modulus of subgrade exceeded 40MPa.
Based on such results, it can be concluded that the FCM bag is particularly suitable for material of the subbase course built on soft subgrade, because of its superior lightness and its prominent attendantness against flexural tension.