Handbook for Bridge Inspections - TSP2

The site conditions may decide which access equipment to be
used. In most cases the best choice wi ll be a bridge lift. When in
use on narrow bridges or during dense traffic, bridge lifts may
restrict the traffic flow. In such cases the inspection shou ld, ifpossib
le, be carried out from a boat, pontoon, raft or an ordinary lift
from underneath the bridge. Suspended working platforms may in
certain cases be a choice.
It is possible 10 combine different types of access equipment. An
ordinary lift can for example be used from a pontoon.
Power lines close to the bridge or the existence of a railroad under
the bridge will often influence upon the choice of access equipment.
During the win ter the inspection can, in some parts of the country,
be carried out from the ice. It is important to first control that the
ice is safe.
In the following chapters different types of access eq uipment are
described.
Ladder
fllSpectiolljrOIll (l
4.2.3 Ladder
For minor bridges or bridges with restricted height, the use of a
ladder may be sufficient to get access. Ladders longer than 4 m
must be secured by appropriate means. Inspectors working alone
are not allowed to work from a ladder.
lifts
4.2.4 Ordinary type of Lifts
Ordinary lifts that operate from ground level with the platfonn
moving upwards may be used for inspection of overhead trusses
and overhead crossing bridges. Ordinary li fts may also be useful
for inspection of bridges with access fo r the equipment from roads
or other hard surfaces under the bridge. The different types are:
* Telescopic lift with scissors action
* A hydrau lic arm with a basket mounted on trailer to be pulled by
car
* A hydraulic ann with a basket mounted on lorry
Scissor lifts
Bascet lifts
Telescopic lifts with sc issors action have rather large work platforms
that move vert ically. The vertical reach is limited to between
5 and 10 metres.
A hydraulic arm with a basket mounted on trai ler to be pul led by
car has a vertical reach from 10 to 20 m and a horizontal reac h
from 5 to 10m depending on the size and make. They are more fl e­
xible in use than te lescopic lifts and have a lifting capacity for two
persons or one person with some equipment.
Handbook for Bri dge Inspections 31