Civil Engineering Reference
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carriageway level. The forces should not be considered to act simultaneously
with any variable load. For some intermediate members where damage to
one of which would not cause collapse (e.g., hangers or stays), smaller forces
may be defined for the studied bridge.
3.5.3.8 Actions on Pedestrian Parapets
Forces that are transferred to the bridge deck by pedestrian parapets should
be taken into account in structural design as variable loads and defined,
depending on the selected loading class of the parapet as stated in EC1.
For loading classes of pedestrian parapets, class C is the recommended min-
imum class. A line force of 1.0 kN/m acting, as a variable load, horizontally
or vertically on the top of the parapet is a recommended minimum value for
footways or footbridges. For service side paths, the recommended minimum
value is 0.8 kN/m. For the design of the supporting structure, if pedestrian
parapets are adequately protected against vehicle collision, the horizontal
actions should be considered as simultaneous with the uniformly distributed
vertical loads. Where pedestrian parapets cannot be considered as adequately
protected against vehicle collisions, the supporting structure should be
designed to sustain an accidental load effect corresponding to 1.25 times
the characteristic resistance of the parapet, exclusive of any variable load.
3.5.4 Actions on Footways, Cycle Tracks, and Footbridges
Load models applicable to footways, cycle tracks, and footbridges are also
covered by EC1. The models comprise a uniformly distributed load
q
fk
and a concentrated load
Q
fwk
that should be used for road and railway brid-
ges and for footbridges, where relevant. All other variable actions and actions
for accidental design situations defined in this section are intended only for
footbridges. EC1 also specifies that for large footbridges (for example, more
than 6 m width), load models defined in this section may not be appropriate
and then complementary load models, with associated combination rules,
may have to be defined for the individual project. Indeed, various human
activities may take place on wide footbridges. Models and representative
values given in this section should be used for serviceability and ultimate
limit state calculations excluding fatigue limit states. EC1 specifies that
the imposed loads defined in this section result from pedestrian and cycle
traffic, minor common construction and maintenance loads (e.g., service
vehicles), and accidental situations. These loads give rise to vertical and hor-
izontal and static and dynamic forces. Loads due to cycle traffic are generally
much lower than those due to pedestrian traffic, and the values given in this
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