Attachment 4 - Site Investigation and Slab Report

 PLASTICITY

 Plasticity is defined by the Liquid Limit of the sample.      Code        Term                Liquid Limit Range (%)
 As such, this term relates only to cohesive soils. Liquid      CL         Low Plasticity      <35
 Limit (LL) is the water content where a soil changes            CI        Medium Plasticity   ≥35 ≤50
 from plastic to liquid in behaviour.                           CH         High Plasticity     >50

 Liquid Limit is measured as a percentage.

 MOISTURE
 This refers to the moisture content of the soil at the time of testing.

 Code      Term            Cohesive Soils                                                  Non-Cohesive Soils
   DR      Dry             Hard, Powdery, Friable                                          Free-flowing, Very Loose
  MO       Moist           Smooth
   DA      Damp            Can be moulded,                                                 Cool, dark, Tends to cohere
  VDA      Very Damp       Sticky
  WE       Wet             Weakened. Free water forms on hands when holding                Cool, dark, Tends to cohere


 CONSISTENCY / DENSITY
 Cohesive soils have consistency.
 Non-Cohesive Soils have relative density.
 Consistency – Cohesive Soils                                                       Density – Non-Cohesive Soils
 Code      Term        Description                                                  Code     Term               Index
    H      Hard        Thumb nail indents with difficulty                            VD      Very Dense         >85
   VSt     Very Stiff  Thumb nail can indent                                          D      Dense              ≥65 ≤85
    St     Stiff       Indented by thumb. Cannot be moulded by hand                  MD      Moderately Dense ≥35 ≤65
    F      Firm        Moulded by strong finger pressure                               L     Loose              ≥15 ≤35
    S      Soft        Moulded by light finger pressure                               LL     Very Loose         <15
   VS      Very Soft   Easily squeezed, sloppy


 ROCK MATERIAL
 Rock Material has Strength and can be Weathered.

 STRENGTH                                                       WEATHERING
Code    Term          Description                             Code Term                        Description
        Extremely     May break after many blows when              Fresh Rock                  No          staining        or
EX                                                             FR
        High          hit with pick. Ringing sound.                                            decomposition
        Very High     Breaks after more than one blow                  Slightly   Weathered    Slightly    discoloured    but
VH                    when hit with pick.         Ringing       SW     Rock                    little/no change in strength
                      sound.
        High          Breaks after one blow when hit                   Distinctly              Highly discoloured usually
 H                                                             DW
                      with pick. Ringing sound.                        Weathered Rock          by iron. Change in strength
        Medium        Readily scored with a knife. Broken              Extremely               ‘Soil’      properties      ie
 M                    in hand with difficulty.                 XW      Weathered Rock          disintegrates or can be
                                                                                               remoulded in water
        Low           Easily scored with a knife.                      Residual Soil           Soil developed from rock –
 L                    Indentations up to 3mm appear             RS                             structure and substance of
                      with firm pick blows. Dull sound                                         rock is no longer evident
        Very Low      Pealed with a knife. Crumbles with
VL                    firm blows. Broken by finger
                      pressure.
        Extremely     Shows soil properties. Easily
 EL
        Low           remoulded by hand