Learning from Earthquakes - Earthquake Engineering for Structural Design - page 89

Figure 3.15 Overturning of building contents (FEMA, 2003)
3.4 LESSONSFORMITIGATIONOFSEISMICRISK
The experiences of so many earthquakes produced in the last period have shown
that the lessons can be related at urban and building levels.
The urban lessons refer to the improving of measures to limit the consequences
of severe earthquakes on a large area scale.
- It is required to avoid high density of population in areas near to known
faults, especially in case of poor soil conditions. The worst examples are
the San Francisco and Kobe earthquakes, where a densely urbanized city
was developed in an area over a fault and liable to liquefaction site.
- Special attention must be paid to the water system serving an earthquake-
prone area. The Shinh-kang Dam was severely damaged during the Taiwan
earthquake (Fig. 3.16), due to the fact that the fault surface line ran across
through the dam; also the water gates were damaged. The resulting
reservoir discharge did not inundate downstream, but the water was
interrupted for some time.
- Strategical centers for the post-earthquake emergency, like hospitals, fire
stations and electrical facilities, police headquarters and so on, must be
invulnerable to seismic effects and placed with direct access from the main
road network. During the Mexico City and Californian earthquakes many
hospitals were seriously damaged, so that they were not operational after
the earthquake (Fig. 3.17).