In areas supporting a portion of a roadbed, retaining wall, or embankment, place backfill in uniform layers at most 8 in. deep (loose. measurement). Compact each layer to meet the density requirements of the roadbed, retaining. wall, embankment material, or as shown on the plans.
A hierarchy (in Greek: often used in Geographic studies á¼±ÎµÏÎ±ÏÏÎ¯Î±, it is derived from á¼±ÎµÏÏÏ -hieros, sacred, and á¼ÏÏÏ -arkho, rule) is a system of ranking and organizing things or people, where each element of the system (except for the top element) is subordinate to a single other element.ost evolutionary biologists assert a hierarchy extending from the level of the specimen (an individual living organism -- say, a single newt), to the species of which it is a member (perhaps the Eastern Newt), outward to further successive levels of genus, family, order, class, phylum, and kingdom.
In a ' branching hierarchy' , one or more objects has a degree of 2 or more (and therefore the maximum degree is 2 or higher). For many people, the word hierarchy automatically evokes an image of a branching hierarchy.wo types of containment hierarchies are the subsumptive containment hierarchy and the compositional containment hierarchy. A subsumptive hierarchy  subsumes  its children, and a compositional hierarchy is  composed  of its children.