Field Materials Testing, Methods & Safety

Question 1

Selecting Fill - Pros and Cons of Soils

Answer 1

See Table 2 in NAVFAC
Organic materials are least desirable for compaction
Well graded gravels and gravel sand mixes are most desirable for compaction

Question 2

Piping in Embankment

Answer 2

Particuarly dangerous for zoned embankments
Internal drainage system D/S of core to mitigate piping
Uniform sand and silty sand and silt have lowest piping resistance
Lean and fat clays or some SC have greatest piping resistance

Question 3

OSHA definition of Trench - width and depth?
Depth required for protective systems?

Answer 3

Narrow excavation –> depth must be greater than width.
Width cannot be greater than 15 ft

Trenches 5 ft deep require protective system, unless made entirely of stable rock

Question 4

Surface lateral deformation measurement method?

Answer 4

Surveying

Question 5

Soil degradation effects on unit weight?

Answer 5

Increase max unit weight in lab