Titel_SS06

0

20

40

60

80

100

Structural

damage

692

Cost of

damages

692

Injuries

60

Remaining and combinations

Usage

Planning and execution

Execution

Planning

(^54)
6
20
46
20
8
14
22
20
40
35
18
5
37
Figure 1.13: Relative distribution of when in the phases of the projects failures and errors originate in
inadequate treatment of risks (Matousek and Schneider (1976)).
In Figure 1.14 a similar illustration is given based on numbers from Stewart and Melchers
(1997), summarizing parts of a number of studies of failures and errors in structural
engineering. In Figure 1.14 it is seen that the distribution found by Matousek and Schneider
(1976) is consistent with other studies; however, it is also seen that the distribution might
deviate when specific types of structures, such as bridges, are considered.
Figure 1.14: Relative distribution of failures and errors in the life-phases of building and bridge
structures (Stewart and Melchers (1997)).
In Figure 1.15 the failures and errors originating in inadequate treatment of risks during the
planning phase are considered in more detail. It is seen that concept and structural analyses in
general contribute the most. When failures and errors leading to economic consequences are
considered, structural analysis dominates. However, in relation to failures and errors leading
to loss of lives and injuries it is seen that also work preparation plays an important role.