Behavior of jointed rock masses during construction of embankment dams
Many sites for embankment dams in Japan are composed of soft, weathered, or jointed rocks. Because these rocks often have many fine joints, it is difficult to reduce the permeability in these rock foundations, particularly in shallow areas, by cement grouting. However, because of the large deformability of these foundations, they will be considerably deformed due to fill placement. If the deformation takes place in a compressive direction and fine joints become narrower, the permeability of the foundation will decrease. The deformation and the change in permeability of foundation due to the fill placement of embankment dams were measured at two dam sites composed of jointed rocks. This paper reports the measurements, and discusses effective and rationalized grouting specifications in consideration of the consolidation influence on the reduction of permeability due to the fill placement in embankment dams.