Defects Flashcards
what causes defects
tectonic forces and pressure relieft
what are joints
defects that exhibit little to o movement parallel to the fracture
what are the important characteristics of a joint
attitude - strikes and dips in a plane, spacing - defines the size of individual blocks, persistence - length, surface morphology
how do joints relate to engineering
failure generally occurs in planes of weakness, meaning that stability of rock mass is based on joints
what are faults
plannar fractures that exhibit movement paralled to the fracture plane
what are the fault plane orientations
dip-sip, strike-slip and oblique slip
what are dip-slips
movement in response to tectonic forces creating vertical and horizontal movement
what are strike slips
movement in response to tectonic shearing creating only horizontal movement; dextral - right, sinstral - left
what are oblique slip faults
a combination of dip and strike slips
what are pwaves
compressional waves which cause the ground to be compressed and dilated in the direction of propagation
what are swaves
transverse waves that displace the ground perpendicular to propagation
what are rayleigh waves
they roll along the ground moving the ground up and down - side to side
what are love waves
roll along the ground causing horizontal shearing
what is liquefaction
unconsoidated sediment that are transformed into a substance that behaves like water due to the shaking
what is lateral spreading
lateral displacement of gently sloping ground as a result of liquefaction in a subsurface area
