civil 200
types of rock
igneous, sedimentary and metamorphic
igneous rock
solidified from magma, volcanic or plutonic
sedimentary rock
mechanically deposited, organically deposited or lithified in place
metamorphic
high heat and/or pressure
atterberg limits
to classify characteristics fine graded soils (silts & clays)
non fine graded = sands and gravel
hydrometer test theory
larger particles have greater settling velocity
process of sedimentary rock
weathering ->erosion/transportation ->deposition ->accumulation -> lithification
lithification process
soils, compaction, cementation
clastic classification
gravel > sand > silt > clay
crustal deformation
rock deposits deformed due to earth processes
tyopes of crustal deformation
compressive, tensional, shearing forces
types of faults
strike-slip, reverse, normal
strike-slip faults
shear, horizontal movement, tectonic forces
normal faults
tensional forces, extensional response, vertical movement
reverse faults
compressional tectonic forces, compressive, shortening, vertical
engineering aspects of deformation and defects
strength (loss due to voids), movement of water (permeability)
weathering types
mechanical/physical, chemical, biological
gravel diameter
>2mm
sands diameter
0.06mm-2mm
fines diameter
<0.06mm
alluvium
transported by rivers/streams, particles get smaller
colluvium
transported by mass movement and surface water flow
residual soils
weathered, (different from sedimentary soils), either chemical/decomposition or mechanical/disintegration
factors that influence weatheringg rate
mineral type, bedding & defects, high rainfall/temp(increases rate), dryer/colder (increases), presence of soil (increases)
how is Liquid limit found
casagrande apparatus (read at N=25) or LL cone penetrometer (read at 20mm)
how is plastic limit found
rolling into threads, (water weight/total soil weight) x 100
what is plasticity index (in words)
the range of water content where soil behaves plastically
liquidity index
state of the natural condition of soil in field
what does water content near or greater than LL mean?
soft, low strength soil
what does water content near PL mean
stiff, strong soil
consistency limits for clay
shrinkage limit -> plastic limit -> liquid limit
effective stress
excess over pore pressure, carried by solid phase
outcrop - sediment process?
done by weathering, erosion, transportation & deposition (WETC)
sedimentary soil - sedimentary rock process?
burial, compaction & cementation (BCc)
sedimentary rock to methamorphic rock process?
Deeper burial, heat & pressure (DBHP)
(Dont be a hoe patrick)
Metamorphic to magma process?
Melting
Extrusive / instrusive igenous rock process?
Burial
Magma to intrusive/extrusive ingeous rock process?
Cooling
Extrusive/Intrusive rock to outcropped rock?
Uplift
Sedimentary or Metamorphic rock to Outcropped rock process?
Uplift