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Engineering design aims to link economic, social, environmental and of course safety factors to produce the best solution. This is especially true in earthquake engineering where it is possible to design a building that is “safe” for all types of earthquakes but does not fit the design brief. For example, it is not economically feasible to design buildings in Bristol to withstand a large earthquake as the chances are very small. Similarly a square concrete structure that has small windows and thick walls may be the ideal design for a particular area; however, it wouldn’t fit a design brief asking for a modern high-tech design. This balance of factors can only be achieved by engineers combining experience and knowledge of the area where the structure is to be located.

Design practice has been changing over the last few years. The older design requirements used to insist that in an earthquake the building should maintain enough structural integrity to remain standing. This meant that if the serviceability limit state was passed the structure would have to be demolished, as it would be no longer safe to use. Although this concept saves lives as people can escape from buildings, it does nothing to prevent the huge financial cost of a large earthquake as a large proportion of buildings have to be demolished and rebuilt. Thus the new design requirements demand that the structure should remain standing in an earthquake and additionally not have to be demolished.

The other factor often left unconsidered is the effect of after shocks. These shocks generally have little effect on undamaged buildings; however, on damaged ones they can have destructive effect and stop rescue operations. In the assessment of buildings the energy from an aftershock should be considered.

Apparently the damage caused by earthquakes is almost entirely associated with man-made structures. Earthquakes only cause death by the damage they induce in structures such as buildings, dams, bridges and other works of man. And this is one of the reasons why earthquake engineering is so important.

1. What is the main idea of the passage?

A)     Earthquake engineers with experience and knowledge.

B)      Some factors for building design in earthquake engineering.

C)     Buildings to withstand all possible earthquakes.

D)     Equal consideration in earthquake engineering.

2. The word “demolish” in the second paragraph means _ _ _ _ _ _ _ _ _ _ _ _ .

A)     pull down        B) pull up        C) pull away        D) pull apart

3. Which of the following is not true about the new design requirement?

A)     Building should remain integrated in an earthquake.

B)      Building should be reconstructed after an earthquake.

C)     Building should let people escape in an earthquake.

D)     Building should be made to avoid rebuilding after an earthquake.

4. The damage of all the following causes the death of people except _ _ _ _ _ _ _ _ _ _ _ _ .

A)     dams and bridges                  B) buildings and dams

C) bridges and buildings                D) some works like steel works and brick works

5. When assessing buildings, we should take into account the _ _ _ _ _ _ _ _ _ _ _ .

A) undamaged buildings                B) man-made structures

C) effect of aftershocks                 D) rescue operations