Civil Engineering Reference
In-Depth Information
FIGURE 2.21
Figure for Prob. 2.2.
TABLE 2.3
Modified Mercalli Intensity Scale
Intensity level
Reaction of observers and types of damage
I
Reactions: Not felt except by a very few people under especially favorable
circumstances.
Damage: No damage.
II
Reactions: Felt only by a few persons at rest, especially on upper floors of
buildings. Many people do not recognize it as an earthquake.
Damage: No damage. Delicately suspended objects may swing.
III
Reactions: Felt quite noticeably indoors, especially on upper floors of buildings.
The vibration is like the passing of a truck, and the duration of the earthquake
may be estimated. However, many people do not recognize it as an earthquake.
Damage: No damage. Standing motor cars may rock slightly.
IV
Reactions: During the day, felt indoors by many, outdoors by a few. At night,
some people are awakened. The sensation is like a heavy truck striking the
building.
Damage: Dishes, windows, and doors are disturbed. Walls make a creaking
sound. Standing motor cars rock noticeably.
