Typical use of fill types depending on application, reinforcement and facing
Table A.1 — Typical combinations of fills, reinforcements and facings
|FILL TYPE||Type 1||Type 2||Type 3||Type 4|
|Geomechanical characteristics||% in weight smaller than 80micron||< 5%||< 12%||12 to 35%||12 to 35%||> 35%||Others|
|% in weight smaller than 20micron||n.a.||n.a.||< 10%||> 10%||< 40%|
|Plasticity Index||n.a.||n.a.||n.a.||< 25||< 25|
|Parts of structure exposed to flooding and/or rapid water draw-down||A||B||B||D||D||D|
|Structure supporting bridge abutments, railways, buildings||A||A||B||C (a)||D||D|
|High reinforced fill walls||A||A||B||B||D||D|
|High reinforced fill slopes||A||A||B||B||C (b)||C (b)|
|Common walls and slopes||A||A||A||B||C (c)||C (c)|
|Smooth strips or rods (metallic or polymeric)||A||A||C (d)||D|
|Ribbed strips or rods, ladders (metallic or polymeric)||A||A||B||C (d)||D|
|Bar mats, ladders, meshes, grids, sheets (metallic or polymeric)||A||A||B||C (d)||D|
|Draining geosynthetics (in-plane permeability)||B||A||A||C (b)|
|KEY:||A = Often Used|
|B = Sometimes Used|
|C = Subject to Specific Study|
|D = Not Recommended|
General The typical combinations above are given for general guidance only and are not intended to be a specification of where various fills or components may be used. The brief descriptions of the fills above are only some of the principle characteristics and do not fully describe a fill. The design documents or a project should specify the particular fills and components which should be used. Fine fill which is too wet of optimum is difficult to compact and likely to cause facings, if used, to go out of alignment during compaction. Fine fill laid and compacted in adverse weather conditions may be problematic. Frost susceptibility should be checked if applied in cold climates.
a If adequate compaction is not achieved then differential settlements between facing and reinforcements may occur which may overload the connection.
b The effect of the drainage properties on the fill characteristics should be assessed.
c Special attention should be paid to: angle of internal friction, compaction procedure with respect to moisture content and climatic conditions, need for drainage layers.
d The fill-reinforcement interaction should be assessed for long term and during construction conditions
e Special attention should be paid to the control of the alignment of the facing units (if any) during construction.