Information response - GEOTECH REPORT

Field Investigation Report cont'd

 

 

 

 

 

 

Client: BROAD, PHIL Job No: 15960
Site Location: Lot 5, No. 528 Black Mountain Road, Cooroy Your Ref:
GLOSSARY OF TERMS
ROCK MATERIAL WEATHERING CLASSIFICATION
Term Symbol Definition
Residual! Soil RS Soil developed on extremely weathered rock; the mass

structure and substance fabric are no longer evident;
there is a large change in volume but the soil has not
been significantly transported.

 

Extremely weathered rock XW Rock is weathered to such an extent that it has ‘soil’
properties, i.e. it either disintegrates or can be
remoulded, in water.

 

Distinctly weathered rock DW Rock strength usually changed by weathering. The rock
may be highly discoloured, usually be ironstaining.
Porosity may be increased by leaching, or may be
decreased due to deposition of weathering products in
pores.

 

Slightly weathered rock Sw Rock is slightly discoloured but shows little or no
change of strength from fresh rock.

 

 

 

Fresh rock FR Rock shows no sign of decomposition or staining

 

STRENGTH OF ROCK MATERIAL

 

 

Term Symbol Point load
index (MPa)
1,50

Field guide to strength

 

Very Low VL >0.03 <0.1 Material crumbles under firm blows with sharp end of
pick; can be peeled with knife; too hard to cut a
triaxial sample by hand. Pieces up to 3cm thick can
be broken by finger pressure.

 

Low L 20.1 <0.3 Easily scored with a knife; indentations imm to 3mm
show in the specimen with firm blows of the pick point;
has dull sound under hammer, A piece of core
150mm long 50mm diameter may be broken by hand.
Sharp edges of core may be friable and break during
handling.

 

Medium M 70.3 <1.0 Readily scored with a knife; a piece of core 150mm
long by 50mm diameter can be broken by hand with
difficulty.

 

High H >4 <3 A piece of core 150mm long by 50mm diameter
cannot be broken by hand but can be broken by a pick
with a single firm blow; rock rings under hammer.

 

 

 

 

 

 

 

 

 

Thursday, 19 May 2011 Page 5 of 5