Angle of repose Angle of repose The angle of repose, or critical angle of repose, of a granular material is the steepest angle of descent or dip relative to the horizontal plane to which a material can be piled without slumping. At this angle, the material on the slope face is on the verge of sliding. The angle of repose can range from 0° to 90°. The morphology of the material affects the angle of repose; smooth, rounded sand grains cannot be piled as steeply as can rough, interlocking sands. The angle of repose can also be affected by additions of solvents. If
Type 90 Kyū-maru procurement plan was established in the 1980s while Japan was experiencing asset price bubble. After the asset price bubble burst in 1991 and the collapse of Soviet Union in 1992, Japan started to cut its defence budget. In order to save budget for Kongo Class missile destroyers and other new weapons, Japan made a plan to reduce the size of its tank force. The production of Type 90 therefore slowed down and part of its budget was shifted to the research and development of the new Type 10 main battle tank. Being 12 tonnes heavier than its predecessor Type 74