Dilatancy (granular material) / internal erosion. The use of appropriate filters is critical to managing these materials; I like a #4 sized clear gravel / coarse-grained sand as a commercial aggregate which is generally readily available. Some non- woven filter fabrics are also suitable. As with all filters, D15 and D50 compatibility criteria should be checked. Dilatancy (granular material) Dilatancy is the volume change observed in granular materials when they are subjected to shear deformations. This effect was first described scientifically by Osborne Reynolds in 1885/1886 and is also known as Reynolds dilatancy. Unlike most other solid materials, the tendency of a compacted
Campden Tunnel Gravel Pit Midlands and the Upper Thames terraces (Evenlode Valley). The site also links with others in the Moreton-in-Marsh area, for example Stretton-on-Fosse. The site is considered precious so it must only be used for research purposes. Campden Tunnel Gravel Pit Campden Tunnel Gravel Pit () is a geological Site of Special Scientific Interest in Gloucestershire, notified in 1988. The site is listed in the 'Cotswold District' Local Plan 2001-2011 (on line). The site exposes a mixture of gravels, sands and silts which make up the Campden Tunnel Drift (Pleistocene period). These are glacial sediments which fill a deep channel. The melt