Liedu Intensity Scale

Unlike the magnitude scales that objectively estimate the released seismic energy, Liedu denotes how strongly an earthquake affects a specific place. It is determined by a combination of subjective evaluations (such as human senses and building damages) and objective kinetic measures. Building damages are further refined with a combination of descriptive qualifiers and a numeric evaluation process.

Liedu I

  • PERCEIVED SHAKING
  • NOT FELT
  • SENSES BY PEOPLE ON THE GROUND
  • Insensible
  • DAMAGES ON BUILDINGS
  • -
  • MEAN DAMAGE INDEX
  • -
  • OTHER DAMAGES
  • -

  • PEAK GROUND ACCELERATION
  • -

Liedu II

  • PERCEIVED SHAKING
  • NOT FELT
  • SENSES BY PEOPLE ON THE GROUND
  • Sensible by very few still indoor people
  • DAMAGES ON BUILDINGS
  • -
  • MEAN DAMAGE INDEX
  • -
  • OTHER DAMAGES
  • -

  • PEAK GROUND ACCELERATION
  • -

Liedu III

  • PERCEIVED SHAKING
  • LIGHT
  • SENSES BY PEOPLE ON THE GROUND
  • Sensible by a few still indoor people
  • DAMAGES ON BUILDINGS
  • Slight rattle of doors and windows
  • MEAN DAMAGE INDEX
  • -
  • OTHER DAMAGES
  • Slight swing of suspended objects

  • PEAK GROUND ACCELERATION
  • -

Liedu IV

  • PERCEIVED SHAKING
  • LIGHT
  • SENSES BY PEOPLE ON THE GROUND
  • Sensible by most people indoors, a few people outdoors; a few wake up from sleep
  • DAMAGES ON BUILDINGS
  • Rattle of doors and windows
  • MEAN DAMAGE INDEX
  • -
  • OTHER DAMAGES
  • Obvious swing of suspended objects; vessels rattle

  • PEAK GROUND ACCELERATION
  • Less than 0.22 m/s²

Liedu V

  • PERCEIVED SHAKING
  • MODERATE
  • SENSES BY PEOPLE ON THE GROUND
  • Commonly sensible by people indoors, sensible by most people outdoors; most wake up from sleep
  • DAMAGES ON BUILDINGS
  • Noise from vibration of doors, windows, and building frames; falling of dusts, small cracks in plasters, falling of some roof tiles, bricks falling from a few roof-top chimneys
  • MEAN DAMAGE INDEX
  • -
  • OTHER DAMAGES
  • Rocking or flipping of unstable objects

  • PEAK GROUND ACCELERATION
  • 0.22–0.44 m/s²

Liedu VI

  • PERCEIVED SHAKING
  • STRONG
  • SENSES BY PEOPLE ON THE GROUND
  • Most unable to stand stably, a few scared to running outdoors
  • DAMAGES ON BUILDINGS
  • Damages - Cracks in the walls, falling of roof tiles, some roof-top chimneys crack or fall apart
  • MEAN DAMAGE INDEX
  • 0 - 0.10
  • OTHER DAMAGES
  • Cracks in river banks and soft soil; occasional burst of sand and water from saturated sand layers; cracks on some standalone chimneys

  • PEAK GROUND ACCELERATION
  • 0.45–0.89 m/s²

Liedu VII

  • PERCEIVED SHAKING
  • VERY STRONG
  • SENSES BY PEOPLE ON THE GROUND
  • Majority scared to running outdoors, sensible by bicycle riders and people in moving motor vehicles
  • DAMAGES ON BUILDINGS
  • Slight destruction - localized destruction, crack, may continue to be used with small repairs or without repair
  • MEAN DAMAGE INDEX
  • 0.11 - 0.30
  • OTHER DAMAGES
  • Collapse of river banks; frequent burst of sand and water from saturated sand layers; many cracks in soft soils; moderate destruction of most standalone chimneys

  • PEAK GROUND ACCELERATION
  • 0.90–1.77 m/s²

Liedu VIII

  • PERCEIVED SHAKING
  • SEVERE
  • SENSES BY PEOPLE ON THE GROUND
  • Most swing about, difficult to walk
  • DAMAGES ON BUILDINGS
  • Moderate destruction - structural destruction occurs, continued usage requires repair
  • MEAN DAMAGE INDEX
  • 0.31 - 0.50
  • OTHER DAMAGES
  • Cracks appear in hard dry soils; severe destruction of most standalone chimneys; tree tops break; death of people and cattle caused by building destruction

  • PEAK GROUND ACCELERATION
  • 1.78–3.53 m/s²

Liedu IX

  • PERCEIVED SHAKING
  • VIOLENT
  • SENSES BY PEOPLE ON THE GROUND
  • Moving people fall
  • DAMAGES ON BUILDINGS
  • Severe destruction - severe structural destruction, localized collapse, difficult to repair
  • MEAN DAMAGE INDEX
  • 0.51 - 0.70
  • OTHER DAMAGES
  • Many cracks in hard dry soils; possible cracks and dislocations in bedrock; frequent landslides and collapses; collapse of many standalone chimneys

  • PEAK GROUND ACCELERATION
  • 3.54–7.07 m/s²

Liedu X+

  • PERCEIVED SHAKING
  • EXTREME
  • SENSES BY PEOPLE ON THE GROUND
  • Bicycle riders may fall; people in unstable state may fall away; sense of being thrown up
  • DAMAGES ON BUILDINGS
  • Most collapse
  • MEAN DAMAGE INDEX
  • 0.71 - 0.90
  • OTHER DAMAGES
  • Cracks in bedrock and earthquake fractures; destruction of bridge arches founded in bedrock; foundation damage or collapse of most standalone chimneys

  • PEAK GROUND ACCELERATION
  • 7.08-14.14 m/s²