Compaction in LBRCTraining of Trainer Personnel on

Environmentally Sound Design and Implementation of Public Works-

Community Roads of the ProductiveSafety Net Program (PSNP)

Compaction in LBRC1. What do we compact?

Soil during earth work on roadGravel during road surfacingFoundation of structures and backfill around

structures (below, around and on top of pipe culvert, pipe culvert, at the back of retaining wall, any fill)

Around miscellaneous structures (scour checks, apron, riprap, etc.)

Compaction in LBRC(cont’d)

2. What other activities go with compaction? Spreading of material like soil or gravel, Watering of the material to be compacted, For good compaction:

Must have optimum moisture content Material preferably be well-graded like:

Gravel 50%, Sand 40%, Silt/clay 10%

Compaction in LBRC (cont’d)

Effect of Watering: High moisture fills voids and makes

compaction difficultVery low moisture does not wet materials

and makes compaction difficultThus, optimum moisture content is very

good for good compaction

Compaction in LBRC (cont’d)

3. What tools and light machinery are used?Hand tools for spreading, level checking, etc.Hand rammers for critical sections of a road

and fill around structures,For large earth work and gravel surfacing:

Tractor or animal pulled dead weight roller Vibratory roller attached to tractor

ILO LBRC Video

Questions or comments from trainees or other

trainers?

Training of Trainer Personnel on Environmentally Sound Design andImplementation of Public Works-

Community Roads of the ProductiveSafety Net Program (PSNP)

June 13-24, 2011Ghion Ambassel Hotel

Dessé, Ethiopia