Selection of Site-specific Stabilization Techniques
5.3.2.2 Labor
A lack of funds can sometimes be overcome if volunteer or low-wage labor is
available. Labor-intensive techniques are:
Hand-placed stone, blocks, or rubble;
Sacks filled with cement mix or other material;
Mattresses of gabions, used tires, lumber, poles, or brush;
Many types of permeable dikes and retards; and
Vegetative treatment.
5.3.2.3 Materials
Ingenious use of locally available materials instead of imported materials can
sometimes compensate for a lack of funds. Some examples are:
Armor of concrete blocks, sacks, soil-cement, or rubble;
Mattresses of used tires or wooden material;
Gabions filled with stream cobbles;
Dikes and retards of timber or scrap metal;
Dikes with a core of local material capped by armor; and
Vegetative treatment.
A materials-related constraint in urbanized areas, or areas where the terrain is difficult
to traverse, is the availability of stockpile and handling areas for bulky materials. A technique
which makes efficient use of easily handled material would then be preferred.
5.3.2.4 Equipment
Equipment availability will not be a factor for projects advertised for construction on
the open market in an area that has general construction contractors. Contractors are usually
quite competent to identify equipment requirements. However, the choice of techniques may
more be restricted for projects to be constructed by the sponsor's employees, or those of some
other specific organization. In that situation, the design engineer should consult with the
appropriate construction personnel early in the planning stage to eliminate impractical
techniques. Equipment rental or contracting-out those features of the work that require
specialized equipment may be feasible. However, problems of coordination and contract
administration frequently occur when the work is subdivided, and should not be considered
unless significant savings in cost or construction time will be gained.
Equipment-related concerns include access to the jobsite, which in turn is affected by
weather, terrain, vegetation, river levels, navigability for floating plant on larger rivers,
feasibility of working in the streambed on smaller streams, environmental impacts, and
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