On the Walkability of Gravel as a Pavement Material in Garden Road from the Walking Posture Analysis

Abstract

A penetrometer is improved to a foot-pressure gauge by installing a circular plate of which area is equivalent to the active foot area. And penetration into gravel layer is measured to estimate the particle movement by force. This is restricted by the scale of road width and depth, penetration rod plate size and by the size of gravel. Penetration into gravel of which size is larger than some special value shows suddenly larger values than expected from the smaller size experiment. This is caused from the random collision between rod and gravel particles. On the other hand, the knee-bending angles and body-rolling acceleration are measured and analysed to know the walkability of gravel pavement. The ratio of the landing interval by both legs to one wave cycle of the knee-bending angle can be considered as the walkability index because this interval can be recognized as that of confirming the safety of walking. The walkability is dependent both on the sinking of the body in small gravel size and on the unevenness in large gravel size.