1. SAFETY& HIRA OF LAUNCHING GIRDER
SUBMMITED BY
RAMASWARUP MISHRA
ROLL NO.-214CH2469
M-tech In Safety Engineering
2. Contents:
Introduction
Main Component of launching girder
Erection procedure
Erection and assembling of launching girder and its components
Safety precautions need to follow during “Erection of front and mid support”
Safety precautions for “Erection of launching girder”
Erection of slider beams
Launching girder load test and winch load test
Safety measures for Auto Launching
Hazard Identification And Risk Assessment
Risk Assessment
Conclusion
3. Introduction:
• Launching girders are most commonly used for placing pre-cast concrete box
segments form viaducts and bridges.
• It is used in congested urban conditions due to their ability to move themselves
forward to the next span.
• It can also accommodate curvature laterally.
• For most situations the balanced cantilever method is the favoured sequence of
construction.
4. Main components of launching girder:
o Main box girder
o Front support
o Middle support
o Rear support
o Rear trolley
o Slider beam
LAYOUT DIAGRAME OF LAUNCHING GIRDER
5. Front Support:
•It is a support consists of telescopic beam which is used for auto launching.
•The front support consist of top beam, a pair of vertical legs, a pair of telescopic
legs, bottom beam.
Middle Support:
• The middle support is seated on the pier head segment. During erection of the
segments most of the erection load is carried by the middle support.
6. Rear Support:
• As Rear Support shares lesser load compared to load shared by Middle Support
therefore the capacity of supporting jacks have been reduced to 100T.
Rear Trolley:
• Launching Girder rests on top beam of this support through PTFE (fixed on
launching girder) versed stainless steel plate (fixed on Rear Trolley).
Slider Beam:
• Horizontal beams over LG for Holding Segment temporarily till completion
of permanent pre-stressing works.
7. Precast segmental erection procedure of launching girder:
Erection and Assembling of Launching girder
Transportation of segments to site
Applying glue/epoxy to match cast surfaces
Aligning and Dry matching of segments
Pressure Grouting
8. Traffic management
Erection of Front Support and Middle Support
LG (5 or 4 boxes)Tandem lifting by using 250 MT Cranes
Erection and Assembling of Launching Girder and its Components:
Stage I
Erection of Segmental first span
Erection of Rear Support
Erection of Rear Trolley
Stage II
10. LG Assembling over Temporary Trestles:
Splicing of Joints with 24 mm dia
tenile bolts or HT Bolts
Torque application of 105 Kg-m
required for tensile bolts
13. Safety precautions need to follow during “Erection of Front and Mid support” :
1. Area preparation and other preparatory work:
1. Area surrounding pier is properly leveled and compacted
2. Top of pier should be properly cleaned and ready to receive structure
3. “Work at height Permit” must be taken and display at the location
4. All mandatory PPEs must be worn by entire team
14. •Prior to start the lifting activity LG boxes or assembled LG must be checked to ensure
structural integrity with respect to quality
• It must be ensured that LG boxes are properly tighten and bolted as per drawing
• LG boxes to be secured properly at ground level
• Lifting points of LG boxes are to be indicated very clearly
•Once LG boxes are lifted top it should be secured properly, and then only load to be
released from the crane
Safety precautions for “Erection of Launching Girder :
15. Erection of Slider Beams:
•Horizontal beams over LG for Holding Segment temporarily till
completion of permanent prestressing works.
•Beams can be moved Horizontally by using Mono strand jacks – 2 Nos
(HT Strands ,Barrel & Wedges)
Weight - 3 MT
Slider
beam is
lifted
with
the
help
crane
16. Launching Girder Load Test and Winch load test:
Load test must be done under
supervision of “Third Party”
The sequence must be followed as
per relevant drawing
Brakes must be applied at Mid
Support in all conditions where
LG is at rest
The winch load test is done at
every 15 minute interval
White rope
with fall
back arrestor
is used for
safety
17. Auto launching:
Shifting of launching girder from one span to other span is known as
auto launching
For launching the launching girder various mechanical/hydraulic jacks,
power section and other things are used .
The power pack machine and mono pulley jack is used , at the time of
launching.
SAFETY IN LG OPERATIONS
19. Safety measures for Auto Launching:
Prior to start auto launching it must be ensured that erected segments are
properly stressed and approved through quality check
Clearance for Auto Launching to be ascertained
Sequence must be followed as per drawing
Prior to remove each support it must be ensured that new locations supports are
provided, checked and made ok.
Each step of removing support and auto launching must have specific check list
which should be ensured at the spot
Load balancing is the most critical safety requirement for auto launching, must
be ensured.
21. Risk Matrix:
Severity (S)
1 2 3 4
Probability(P)
1 1 2 3 4
2 2 4 6 8
3 3 6 9 12
4 4 8 12 16
Green indicates “
low risk”
Yellow indicates
“moderate risk”
Red indicates “
high risk”
From 1 to 3, it is low risk.
From 4 to 8, it is moderate risk
From 9 to 16, it is very high level of risk
22. SEVERITY VALUE PROBABILITY
FATAL 4 Event which is certain to occur.
Reportable injury 3 Event which occur in most circumstance
Non-reportable injury 2 Event which occur exceptional circumstance
Injury 1 Event which occur in moderately
23. Risk Assessment:
SL
.
N
O.
Activity/
Observation
Hazard Risk
Involved
Proba
bility(
P)
SEVE
RITY
(S)
Total
Risk
Existing Control measure Control measure
to be taken
Proba
bility
Se
ve
rit
y
Residu
al Risk
1 Lifting Operation Falling from
height
Heating of
object
Structural
Collapse
Multiple
facture
3 4 12(H) ASLI & limit switch is installed in
lifting equipment
SWL load of hitch is calculated
before lifting
Lifting permit should be
taken.
Lifting plan is to be
prepared , before lifting.
2 1 2(L)
2 Transportation of LG Traffic
mismanagement
Collision with
other vehicle
Road
accident
4 4 16(H) Periodic inspection of trailer is to
be done.
Component should be tied of with
chains & turn buckles.
Traffic marshal should be
provided with trailer .
Valid fitness tag should
be given.
1 6 6(M)
3 LG erection &
alignment
Heating of
moving object
Failure of hand
held tool
Cut injury
Crush injury
3 2 6(L) Specific lifting plan is prepared
before lifting.
All lifting tool/ tackles should have
valid TPC.
No one should be allowed
to work under the
suspended load.
TBT should be conducted.
2 1 2(L)
4 Trestle foundation &
erection
Heating by
moving object
Hit injury
Crush injury
Crush
3 3 9(H) Tag line is provided in suspended
load.
Monthly inspection & colour coding
of tools & tackles is done.
ASLI & limit switch should
be installed on lifting
equipment.
Lifting is to be carried out
through competent
person.
1 3 3(L)
5 Electrical Installation Electrical shock Burn
Electrocution
3 4 12(H) Competent person is engaged in electrical
installation work.
Proper earthling is done.
LOTO is to be implemented.
4 2 8(M)
24. Nuts & bolts
are not
tighten.
Proper
inspection is
not taken
Nuts & bolts are
tighten properly.
TBT should be
conducted
Risk Assessment ( Tightenof nuts & bolts ):
Hazard:
Injury, facture , crush etc…
Existing control measure:
Nuts & bolts are tighten.
TBT should be conducted.
Probability: 3
Total Risk : 6(M)
Severity: 2
Additional control measure:
Proper inspection
should be conducted.
Corroded parts are to
be greased by some
liquid substance.
Probability: 2
Total Risk:2(L)
Severity: 1
25. Conclusion:
While ,I have worked through the launching girder , I have observed that various
type of hazards present in LG . By which the risk level also increases
tremendously in a high rate . So, to minimise the risk level , I have added some
control measures .
The safety work method is needed to look through the matter of the risk
assessment. The most important aspect of the demonstrated methodology is that it
encourages the designer to examine the potential consequences of failure, and to
consider appropriate safety levels commensurate with the risk.
As , HIRA plays a vital role for knowing the risk assessment and also hazard
present within the activity , which can be controlled by the additional control
measure which is taken by me.
