Ethical issues in engineering design - 3TU.Centre for Ethics and ...

Design of a bridge
geotechnical codes could be used. These codes differ and can lead to different
required material thicknesses and qualities. In the construction codes the
principal loads are vertical and come from the road onto the wall. Using a
geotechnical code the principal loads will be horizontal, and due to the force
exerted by the soil which will push against the wall. According to the engineers
interviewed it is uncommon for a choice to have to be made between different
types of codes but it does occur as it did in the bridge case. The engineers
indicated that what code is chosen for the calculations is based on experience
with similar situations.
People and drivers on the bridge participate in traffic, thus, all traffic safety
legislation is relevant for a road bridge. All the requirements pertaining to traffic
safety, such as the width of the bridge, protecting of cyclists and pedestrians
from cars and illuminating the roads, must be included in the design process.
The IBA did not design the road deck on the bridge, this was the responsibility
of the DRO. The IBA only made the engineering design for the bridge. Because
exact division of the bridge into road, pavement, cycle path etc was not done by
the IBA and was not that important with regard to the construction of the bridge
I will not get into the details of regulation and codes pertaining to road. It was,
however, important for this engineering design to take into account the fact that
traffic accidents can happen on a bridge. A car or truck might crash into the
guard rail on one of the sides of the bridge or crash into a load bearing structure
of a bridge. A bridge should not collapse in such exceptional circumstances. The
codes include rules for calculations that should be made to simulate cars or
trucks crashing into the load bearing structures of the bridge and for trucks
standing very near to the sides of a bridge.
The IJburg bridge will be partly on publicly accessible terrain, so it is possible for
people to access all parts of the bridge. People will be walking or cycling on the
bridge. The bridge will be about 9 meters above water level and the arches will
be about 22 meters above the bridge deck. The building decree requires that
preventive measures should be in place to prevent people being blown of the
bridge in high winds. To protect cyclists and pedestrians on the bridge a rail will
be installed on the bridge, using building decree guidelines.
In the preliminary design phase no measures to prevent people from
climbing on the arches were taken into account. One of the engineers said in an
interview that he thought that something should be done to prevent people from
climbing onto the arches because the arches were not steep, the inclination is
such that it might be possible to walk on the arch. The arches of some arched
bridges are so steep that it is impossible to climb on them. In this case, the
engineer thought that a gate to prevent people from walking onto the arch might
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