Post on 28-Aug-2014
DELHI METRO RAIL CORPORATION
ELEVATED VIADUCT FROM KM 0.62 TO KM 8.00 ON BARAKHAMBA ROAD – CONNAUGHT PLACE – DWARKA
SECTION (LINE NO.3) 3C21R
METHOD STATEMENT FOR LAUNCHING OF SEGMENTS
Document No : 215/DMRC/3C21R/MS-13/R-1Pages : 1 TO 141Date : 09.04.2004
CONTRACTORS:IJM-NBCC-VRM JV
CONSULTANTS:
ARCH CONSULTANCY SERVICES (P) LTD.IN ASSOCIATION WITH
BRIDGECON INDIA
CONTENTS
1.0 INTRODUCTION
1.1 Configuration requirement for Delhi metro project
1.1 Drawings
1.2 Steel Fabrication
1.3 Safety
2.0 MAIN COMPONENTS OF LAUNCHING GIRDER
2.1 General
2.2 Main Box Girder
2.3 Front Support
2.4 Middle Support
2.5 Rear Support
2.6 Rear Trolley
2.7 Slider Beam
2.8 Moving Trolley
2.9 Counter Weight
2.10 Fixed Mounted Hoist
2.11 Platform / Walk way
3.0 SCHEME FOR AUTOLAUNCHING
3.1 General
3.2 List of Drawings for ready reference
3.3 Steps for Auto Launching
4.0 STAGES OF ERECTION OF SPAN
4.1 General
4.2 List of Drawing
4.3.1 Erection Procedure for 31.0m Span
4.3.2 Erection Sequence of Precast Segments in Different Span
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5.0 MANUAL FOR ERECTION OF FIRST SPAN
5.1 General
5.2 List of Drawings
5.3 Erection of Launching Girder in First Span.
6.0 REFERENCES
ANNEXURE A
PROCEDURE FOR VERTICAL ROTATION
A.1 General
A.2 Detailed Description of Various Conditions of Launching Girder in Vertical
Grade & Corresponding Height Adjustment of its Supports.
A.2.1 Down Grade
A.2.2 Up Grade
A.3 Permissible Range of Height to be Ensured at Front Support
A.4 Calculation of Height at Front Support For a Known Height at Rear Trolley
and Middle Support
A.4.1 Down Grade
A.4.2 Up Grade
ANNEXURE B
PROCEDURE FOR MOVEMENT OF MIDDLE SUPPORT / REAR
SUPPORT USING MOVING TROLLEY
ANNEXURE C
PROCEDURE FOR RAISING / LOWERING OF TELESCOPIC LEG /
BOTTOM BEAM OF FRONT SUPPORT
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1.0 INTRODUCTION
This document has been specifically written for the Launching Girder to be used in
DMRC Project: BARAKHAMBA ROAD – CONNAUGHT PLACE – DWARKA
SECTION (LINE NO.3)
This document covers following sections:-
(a) Description of Launching Girder
(b) Scheme for Auto Launching & Erection
(c) Description of Operations performed by various parts of Launching Girder.
(d) Safety
1.1 CONFIGURATION REQUIREMENT FOR DELHI METRO PROJECT
This section includes requirements and information regarding the configuration of the
bridge and Launching Girder
S.No. Item Criteria
1. Maximum span length 31.0m
2. Minimum span length 16.0m
3. Maximum longitudinal slope 2.74%
4. Maximum weight of segment 80.0 t
5. Maximum length of segment 3.0m
6. Minimum Horizontal radius 302.05m
7. Total height of intermediate segment 2.0m
8. Total height of end segment 3.0m
9. Segments gluded or dry jointed Epoxy Glue
10. Loading of segments from ground / rear From ground only
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1.2 DRAWINGS:
The following drawings apply to DMRC project:
S. No. Title Drawing No.
1. General Arrangement of Launching Girder 215/LG/01
2. Details of Launching Girder (Sh.1 of 3) 215/LG/02
3. Details of Launching Girder (Sh.2 of 3) 215/LG/02
4. Details of Launching Girder (Sh.3 of 3) 215/LG/02
5. Details of Monorail 215/LG/03
6. General Arrangement Erection stage lifting 215/LG/04
7. Details of wire rope assembly for intermediate segment 215/LG/05
8. Scheme for auto launching (Sh.1 of 3) 215/LG/06
9. Scheme for auto launching (Sh.2 of 3) 215/LG/06
10. Scheme for auto launching (Sh.3 of 3) 215/LG/06
11. Details of Middle Support (Sh.1 of 7) 215/LG/07
12. Details of Middle Support (Sh.2 of 7) 215/LG/07
13. Details of Middle Support (Sh.3 of 7) 215/LG/07
14. Details of Middle Support (Sh.4 of 7) 215/LG/07
15. Details of Middle Support (Sh.5 of 7) 215/LG/07
16. Details of Middle Support (Sh.6 of 7) 215/LG/07
17. Details of Middle Support (Sh.7 of 7) 215/LG/07
18. Details of Front Support (Sh.1 of 6) 215/LG/08
19. Details of Front Support (Sh.2 of 6) 215/LG/08
20. Details of Front Support (Sh.3 of 6) 215/LG/08
21. Details of Front Support (Sh.4 of 6) 215/LG/08
22. Details of Front Support (Sh.5 of 6) 215/LG/08
23. Details of Front Support (Sh.6 of 6) 215/LG/08
24. Details of Rear Support (Sh.1 of 3) 215/LG/09
25. Details of Rear Support (Sh.2 of 3) 215/LG/09
26. Details of Rear Support (Sh.3 of 3) 215/LG/09
27. Details of Rear Trolley (Sh.1 of 5) 215/LG/10
28. Details of Rear Trolley (Sh.2 of 5) 215/LG/10
29. Details of Rear Trolley (Sh.3 of 5) 215/LG/10
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30. Details of Rear Trolley (Sh.4 of 5) 215/LG/10
31. Details of Rear Trolley (Sh.5 of 5) 215/LG/10
32. Details of Sliding Beam (Sh.1 of 2) 215/LG/11
33. Details of Sliding Beam (Sh.2 of 2) 215/LG/11
34. General Arrangement for Temporary Prestressing (25.0m) 215/LG/12
35. Details of Lifting & Temporary Prestressing for End
Segments Erection Stage (Sh.1 of 4)
215/LG/13
36. Details of Lifting & Temporary Prestressing for End
Segments Erection Stage (Sh.2 of 4)
215/LG/13
37. Details of Lifting & Temporary Prestressing for End
Segments Erection Stage (Sh.3 of 4)
215/LG/13
38. Details of Lifting & Temporary Prestressing for End
Segments Erection Stage (Sh.4 of 4)
215/LG/13
39. Details of Lifting & Temporary Prestressing for Intermediate
Segments Erection Stage (Sh.1 of 6)
215/LG/14
40. Details of Lifting & Temporary Prestressing for Intermediate
Segments Erection Stage (Sh.2 of 6)
215/LG/14
41. Details of Lifting & Temporary Prestressing for Intermediate
Segments Erection Stage (Sh.3 of 6)
215/LG/14
42. Details of Lifting & Temporary Prestressing for Intermediate
Segments Erection Stage (Sh.4 of 6)
215/LG/14
43. Details of Lifting & Temporary Prestressing for Intermediate
Segments Erection Stage (Sh.5 of 6)
215/LG/14
44. Details of Lifting & Temporary Prestressing for Intermediate
Segments Erection Stage (Sh.6 of 6)
215/LG/14
45. Scheme for Erection of precast segments (Sh.1 of 2) 215/LG/15
46. Scheme for Erection of precast segments (Sh.2 of 2) 215/LG/15
47. Details of Bracket for fixed-mounting-hoist 215/LG/16
48. Details of counter weight 215/LG/17
49. Erection sequence of launching girder in first Span (Sh.1 of 3) 215/LG/18
50. Erection sequence of launching girder in first Span (Sh.2 of 3) 215/LG/18
51. Erection sequence of launching girder in first Span (Sh.3 of 3) 215/LG/18
Note: A complete set of above drawings should be available at site for ready reference.
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1.3 STEEL FABRICATION
The Launching Girder including all its accessories will be fabricated with the
drawings supplied by Arch Consultancy Pvt. Ltd. unless otherwise communicated
through a written document.
Items modified or rectified during assembly shall be reported for discussion & final
details must be supplied to Arch Consultancy Services Pvt. Ltd.
1.4 SAFETY
Safety shall be ensured as per safety manual.
This manual should include the following information:
- Safety Personnel
- Site Training
- Personal Protection Equipments i.e. safety boots, safety nets.
- Lifting of parts and equipments
- Use of flame cutter and welding sets
- Storm wind / Emergency conditions
- High power cable
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2.0 MAIN COMPONENTS OF LAUNCHING GIRDER
2.1 General
This sections gives a brief description of main parts of Launching Girder. Reference
shall be made to the detailed drawings.
This section is built up as follows:
Main Box Girder……………..(Refer Drg .No. LG /02 sheet 1 of 3 to 3 of 3)
Front Support………….……..(Refer Drg .No. LG /08 sheet 1 of 6 to 6 of 6)
Middle Support………..……..(Refer Drg .No. LG /07 sheet 1 of 7 to 7 of 7)
Rear Support……….…….…..(Refer Drg .No. LG /09 sheet 1 of 3 to 3 of 3)
Rear Trolley……….………....(Refer Drg .No. LG /10 sheet 1 of 5 to 5 of 5)
Slider Beams……….………...(Refer Drg .No. LG /11 sheet 1 of 2 to 2 of 2)
Moving Trolley……...……….(Refer Sketch No. LG/SK-02)
Counter Weight……………....(Refer Drg .No. LG /17)
Fixed Mounted Hoist…….…..(Refer Drg .No. LG /16)
Platform / Walk ways…….…..
2.2 Main Box Girder
Main Box Girder has been split in seven close plate girder (box type steel structures)
of length 9.250m each. These are spliced at their ends with the help of 24 dia. HSFG
bolts. The details of splicing & bolting arrangements have been shown in drawing no.
(LG/02 Sheet 1 of 3 to Sheet 3 of 3).
Bearing stiffeners have been provided at all support locations covering all span
ranges. In addition normal stiffeners are also provided at 975 c/c.
The Launching Girder main box structure rests on four supports viz.
Front Support
Middle Support
Rear Support
Rear Trolley
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2.3 Front Support
Front Support consists of following parts
Top Beam
Top vertical leg
Telescopic leg
Bottom Beam
Slide bracing & Tie members
This support has in built ability for adjustment of height depending upon the situation
encountered at the site. This flexibility is provided by the telescopic leg which can
move into the top vertical leg & can be locked using 100Ø pin provided in the
support. The tie members are fixed to the top vertical leg. The side bracing connects
top vertical leg with the bottom beam. The change in length of side bracing during
adjustment in height of support can be partially done by changing its points of
connection with vertical leg for which four different connection holes have been
provided & partially by 300mm long screw jack provided at its bottom.
The entire support rest on concrete pedestals provided in the pier cap as shown in the
drawing no. LG/08, The Front Support is secured to the pier cap using 32Φ anchor
bolts.
Note: Maximum height of the front support = 5370mm
Minimum height of the front support = 3690mm
Measured from top of support to bottom of its bottom beam.
The front support is fixed at 2500 mm from the front of the launcher. Two nos.
vertical hydraulic jacks (150t capacity) are provided to carry out vertical adjustment
of the support. Side shifting of front support with respect to Launching Girder is not
possible.
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2.4 Middle Support
The middle support is positioned on the rear pier segment and supports the launching
girder together with the front support during the span erection. The level of middle
support can be varied using 4 number single acting hydraulic jacks, (200T capacity).
Middle Support consist of following main parts
(1) Side beam B2 – 2nos.
(2) Cross beam B1
(3) Launching bearing – 2nos.
3.1 Longitudinal sliding bearing
3.2 Kunckle bearing
3.3 Cradle
(4) Longitudinal pushing assembly
(5) Braking assembly
Side beams (B2) rests over 200t capacity single acting jacks as shown in the drawing
no. LG/07 & forms the basic supporting structure of middle support. Side Beams (B2)
are connected by cross beam B1 provided at its top. Cross beam provide support and
sliding surface (Stain less Steel top) for the Launching Bearing.
Launching Bearing consists of three parts
a) Longitudinal sliding bearing which consists of a sliding surface over which the
launching girder slides during auto launching process.
b) Knuckle bearing, it consist of a 165Ø pin connecting four vertical plates. The
launching girder can be vertically rotated over this knuckle pin.
c) Cradle consists of a vertical pin embedded into steel stool over which the whole
Launching girder can rotate horizontally. It is provided with a PTFF sliding
surface at its bottom side, which assists its transverse movement over cross beam
– B1.
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The whole assembly of launching-bearing can be pulled when required by the help of
macalloy bar connecting the cross B1 & the cradle to ensure proper position of the
launching bearing with respect to the cross beam B1.
Longitudinal pushing assembly is an independent device attached to the monorail on
front side of middle support through longitudinal movement jack connected to a
bracket provided at center of plate connecting the two cradles. This assembly is
responsible for forward movement of launching girder during auto launching
operation.
Braking assembly is another independent assembly provided at the rear side of middle
support. It is mounted on monorail & can be connected to the middle support through
40Ø pin as shown in the drawing LG/07. When this assembly is connected to the
support it restricts forward movement of launching girder with respect to the support.
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2.5 Rear Support:-
Rear Support is a replica of middle support except that longitudinal pushing assembly
is not provided in this support. As rear support shares lesser load compared to load
shared by middle support therefore the capacity of supporting jacks have been
restricted to 100t as shown in the detail drawing LG/09.
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2.6 Rear Trolley
The Rear trolley is positioned 4450mm from the rear end of the main box girder and
provides support during longitudinal launching.
It is A type truss supported on eight wheels which rests on 90R rails laid on the
erected superstructure at a spacing of 4.7m c/c.
The top beam of the truss is connected through four no knuckle pins so that it can
rotate vertically if required & maintain proper contact with the Launching Girder.
Launching Girder rest directly on the top beam of this support through SS verses SS
interface provided between the two.
After launching along a curved span, it is necessary for the main box to be side shifted
on the rear trolley. Macalloy bars have been provided to pull the main box over
stainless steel plates fixed on top beam of the rear trolley.
The Launching Girder can be locked with respect to this support with the help of four
set of macalloys bars passing through brackets provided in launching girder &
movable bracket consisting of two ISMC 200 & bolted at top & bottom end.
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2.7 Slider Beams
Slider beams are independent assembly of two built up I sections connected together
with the help of stiffeners. Slider beams rests on 40 x 40 plate with 3 thick SS plate
fitted on top of launching girder main box as shown in drawing no.LG/02.
The slider beams are provided with two suspender bars at each end, which can move
500mm on either side in transverse direction while maintaining a constant distance of
5.8m among themselves.
The tension bars are connected to two beams that have been secured to the precast
segment. Vertical adjustment is carried out using the vertical tension bars while
transverse movement is done using the horizontal jacks positioned on top of the slider
beam.
The longitudinal position of segment / slider beam is adjusted through a cable running
through all the slider beams which is pulled by two monojack fitted at extreme ends
of the launching girder main box.
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2.8 Moving Trolley
Moving trolley is an independent device consisting of two stools resting on a platform
mounted on four wheels. It is mainly used for forward movement of middle support &
rear support.
Moving trolley is also useful for temporarily supporting the rear support & middle
support for minor repair / maintenance of supporting jacks.
Note: Moving trolley is not designed for supporting middle support or rear support
during erection & the same shall be avoided.
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2.9 Counter Weight
A counterweight is provided in the form of pre-cast concrete segments, which will
remain fixed at the rear end of Launching girder during entire launching process
unless otherwise specified in some special circumstances. This counter weight
balances the launcher during auto launching of the Launching Girder.
2.10 Fixed Mounted Hoist
It is a electrically operated device fixed over a bracket provided at 13.4m from the
front end of the Launching Girder. It has a lifting capacity of 80 t & is meant for
lifting of precast segment during erection stage.
2.11 Platform / Walk way
Working platforms have been provided at all the supports for operating mechanisms
associated with each support. Details of access plat forms have been provided in the
detailed drawings of the supports.
The main body of the Launching Girder is a close – box type structure with a width of
2.0m so that persons operating the Launching Girder can walk along its entire length
when required. However, in general practice, a separate ladder shall be used wherever
permanent access is not provided.
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3.0 SCHEME FOR AUTOLAUNCHING OF LAUNCHING GIRDER
3.1 GENERAL
The term auto launching used here stands for forward movement of Launching
Girder from already erected span to the span to be erected.
This section gives a simplified step-by-step sequence of auto launching of
Launching girder in chronological order of auto launching process. Extracts
from various drawings have been incorporated for ready reference to site
engineers.
To simplify and to avoid mishapenings during auto launching several
checklists have been presented along with the following detail, which shall be
strictly adhered by the construction engineers.
3.2 LIST OF DRAWINGS FOR READY REFERENCE
Drawing nos. Title
LG/06
(Sh. 1 of 3 to Sh. 3 of 3)
Scheme for Auto Launching
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3.3 STEPS FOR AUTO LAUNCHING
STAGE – 1
Step 1 The Launching Girder rests on the already erected span as shown.
Step 2 Bring the slider beams backward so that one slider beam rests at 4.45 m from
the end of Launching Girder (Near Rear Trolley) & all other slider beams rests
in succession at spacing of 0.9m.
Step 3 Affix the 90 R rails on the newly erected span for further movement of
Launching Girder.
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STAGE – 2
Step 1 Remove the brakes provided at middle support by removing pins connecting
monorail & the braking assembly.
Step 2 Check the Jacks of Rear Support & ensure that it experiences a minimum
reaction of 10tonnes (total reaction on four jacks) on it.
Step 3 Position the moving trolley below the middle support exactly at the center of
it.
Step 4 Close the jack of middle support so that the reaction on the jack of middle
support is fully released. As a result of which, the reactions will be transferred
on the jacks of rear support & the middle support finally rests on the moving
trolley.
Note: Allowable reaction to be transferred on intermediate segment through rear
support = 120tonnes
Step 5 Open the anchors of middle support to allow its forward movement.
Step 6 Move the middle support with the help of moving trolley & position it over the
front pier segment of newly erected span so that a distance of 0.9 m is
achieved between the expansion joint of the span & centerline of the middle
support.
(Refer sketch showing position of middle support over pier segment in plan on
next page)
Note: Refer detailed procedure for movement of middle support /rear support using
moving trolley from annexure B.
Step 7 Open the jacks of middle support to transfer a minimum reaction of 10tonnes
on it ensuring that the moving trolley is released.
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Step 8 Anchor the middle support (i.e. tie it with the pier segment). Now move the
moving trolley from the middle support position & place it below rear support.
Step 9 Apply brakes at middle support.
Step 10 Remove the brakes provided at rear support by removing pins connecting
monorail & the braking assembly.
Step 11 Close the jacks of rear support so that the reaction on jacks is fully released as
a result of which the reaction will be transferred automatically over jacks of
middle support & the rear support finally rests on the moving trolley.
Step 12 Open the anchors of rear support to allow its forward movement.
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STAGE - 3
Step 1 Move the rear support with the help of moving trolley & position it over pier
segment as shown so that a distance of 0.9m is achieved between center line
expansion joint of the span & the center line of the rear support.
(Refer sketch showing position of rear support over pier segment in plan on
next page)
Note: Refer detailed procedure for movement of middle support /rear support using
moving trolley from annexure B.
Step 2 Anchor the rear support at this position (i.e. tie it with the pier segment).
Step 3 Open the jacks of rear support so that the jacks experiences a reaction of
10tonnes (total reaction on four jacks) on it.
Step 4 Apply brakes at rear support.
Step 5 Move the moving trolley from rear support position & place it below middle
support.
Step 6 Remove the brakes provided at middle support by removing pins connecting
monorail & the braking assembly.
Step 7 Close the jacks of middle support so that the reaction on jacks is fully released
as a result of which, the reaction will be transferred over jacks of rear support
& the middle support rests over moving trolley.
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STAGE - 4
Step 1 Move the middle support & position it over front pier segment of the newly
erected span so that a distance of 0.9m is achieved between centerline
expansion joint of the span & the centerline of middle support as shown.
(Refer sketch showing position of middle support over pier segment in plan on
next page)
Step 2 Open the jacks of middle support to transfer a reaction of 10tonnes (total
reaction on four jacks) on it.
Step 3 Anchor the middle support (i.e. tie it with the pier segment).
Step 4 Attach longitudinal movement jack with the middle support
Step 5 Remove the 100Ø pin provided in the telescopic leg of the front support using
jacks provided over the bottom beam of front support.
Step 6 Close the jacks of the front support & remove the jacks along with stools
provided, so that the reaction is fully transferred to the middle support.
STAGE - 5
Step 1 Close the telescopic leg of front support to its minimum length as shown in the
drawing and lock it in this position so that the front support hangs over the
launching girder.
Note: Refer detailed procedure for lowering / raising of bottom beam/ telescopic leg
of front support from annexure C.
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STAGE – 6
Step 1 Rotate the Launching Girder vertically by lowering the jacks of rear support so
that the bottom of launching girder rests over the top beam of rear trolley.
Procedure for vertical rotation
1. Lock the knuckle pins of rear trolley using 20 bars provided on its both sides.
2. Close the jacks provided in box S-7 of Launching Girder
3. Lower the jacks of rear support until the bottom of launching girder touches
the top of rear trolley.
Note: In case the minimum height of rear support is achieved before achieving
contact between launching girder & rear trolley then the same can be achieved
by raising the jacks of middle support.
4. Remove the 20 bars provided on the sides of Knuckle pins of rear trolley to
allow free rotation of Knuckle pins in vertical plane.
Step 2 Align the Girder horizontally by pulling macalloy bar at rear trolley so that
centerline of Launching Girder passes through the center of middle support
and rear trolley.
For straight span this step is not required.
PROCEDURE FOR HORIZONTAL ROTATION
1. Ensure that the Rear Trolley, Rear Support & Middle Support are properly
anchored at their respective positions.
2. Ensure that the Front Support telescopic leg is closed to its minimum so that
there is no possibility of clash between brackets / projections in bottom beam
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of the front support & the pier segment of the already erected span & the shear
key provided at the pier cap during rotation.
3. Loosen the Macalloy bars connecting the launching girder with top beam of
the rear trolley
Note: Do not remove the channels provided below top beam for anchoring unless it
is required to cross the knuckle pins.
4. Anchor the middle support cradles using the Macalloy bars provided over the
cross beam B1 so that it doesn’t get pulled during rotation process.
Note: The cradles must be connected to each other by a suitable system so that their
c/c distance of 1.8m is maintained during rotation.
5. Clamp the anchor plates of longitudinal sliding bearing of middle support &
rear support as shown.
(Refer sketch on next page)
6. Loosen the macalloy bar anchor provided at top of cross beam B1X at rear
support so that the cradles are free to move in the required direction along with
the launching girder while it is pulled at rear trolley for rotation.
Note: The cradles must be connected to each other by a suitable system so that their
c/c distance of 1.8m is maintained during rotation.
7. Lock the knuckle pins of rear trolley using 20 bars provided on its both sides.
8. Pull the launching girder in the required direction using macalloy bars
provided on the side face of top beam of rear trolley so that launching girder
slides over top beam to the center of rear trolley.
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9. Put the 100Ø vertical pin passing through the launching girder bottom flange
& the center of the top flange of top beam of rear trolley.
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Note: In case the holes provided in the launching girder & the top beam flanges does
not match after rotation adjust them by pulling launching girder longitudinally
using the turn buckles provided at the center of top beam of the rear trolley.
10. After horizontal rotation the centerline of Launching Girder should pass
through the center of rear trolley and middle support, the placement of 100Ø
pin will ensure it at rear trolley however at middle support it shall be checked
and rectified if wrong by pulling the cradles using macalloy bar provided in
transverse direction over top of cross beam B1 of middle support.
Note: The cradles must be connected to each other by a suitable system so that their
c/c distance of 1.8m is maintained.
11. Anchor the middle support cradles using the Macalloy bars provided over the
cross beam B1 so that it doesn’t move in transverse direction during
auto launching.
Note: Macalloy bar anchor provided at top of cross beam B1X at rear support shall
remain loose during auto launching so that the cradles are free to move in the
required direction along with the launching girder while it is auto launched
along a curved span.
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STAGE - 7
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Step 1 Remove the anchors of rear trolley to allow its forward movement.
Step 2 Remove the 20 bars provided on the sides of Knuckle pins of rear trolley to
allow free rotation of Knuckle pins in vertical plane.
Step 3 Unclamp the anchor plates of longitudinal sliding bearing of middle support &
rear support as shown so that the Launching girder is guided by the rollers
during further auto launching.
(Refer sketch on next page)
Step 4 Remove brakes provided in the middle support & rear support.
Step 5 Start pushing the launching girder using longitudinal movement jack provided
in front of middle support, so that the launching girder slides over the middle
support & rear support & the rear trolley moves along with the launching
girder on rails provided along the erected span.
Step 6 Continue pushing of Launching Girder until the rear trolley reaches close to
the rear support so that the further movement is not possible.
Note: A minimum clear distance of 300mm between rear trolley and rear support
must be ensured
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STAGE – 8
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Step 1 Remove anchors of rear support.
Step 2 Lower the jacks of rear support and move rear support using moving trolley
and position it over S-9 segment as shown.
Note: Do not open the jacks of rear support so that it remains inactive during further
auto launching.
Step 3 Anchor the rear support at this location.
STAGE – 9
Step 1 Start pushing launching girder again using longitudinal movement jack
provided in front of middle support so that the front support reaches the next
pier location as shown in the drawing.
Note: Brakes shall be applied at middle support in all conditions where launching
girder is at rest or auto launching has stopped / completed.
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STAGE – 10
For straight span this stage is not required.
Step 1 For curved span remove the 100 vertical pin passing through center of top
beam of rear trolley and launching girder & rotate the launching girder about
middle support by pulling macalloy bar provided along the top beam of the
rear trolley so that the launching girder is now aligned along the chord of next
span to be erected.
PROCEDURE FOR HORIZONTAL ROTATION
1. Ensure cantilever of length equal to (Span to be erected + 4.250) in meters
measured from centerline of middle support to front end of launching girder.
2. Apply brakes at middle support. {Incase the holes provided in monorail and
braking system does not match the launching girder shall be auto launched
forward by few millimeters (Less than 100mm)}
3. Ensure that the Rear Trolley, Rear Support & Middle Support are properly
anchored at their respective positions.
4. Ensure that the Front Support telescopic leg is closed to its minimum so that
there is no possibility of clash between brackets / projections in bottom beam
of the front support & the pier segment of the already erected span & the shear
key provided at the pier cap during rotation.
5. Loosen the vertical Macalloy bars connecting the launching girder with top
beam of the rear trolley
Note: Do not remove the channels provided below top beam for anchoring unless it
is required to cross the knuckle pins.
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6. Anchor the middle support cradles using the Macalloy bars provided over the
cross beam B1 so that it doesn’t get pulled during rotation process.
Note: The cradles must be connected to each other by a suitable system so that their
c/c distance of 1.8m is maintained during rotation.
7. Clamp the anchor plates of longitudinal sliding bearing of middle support as
shown.
(Refer sketch shown in stage 6 of auto launching)
8. Loosen the macalloy bar anchor provided at top of cross beam B1X at rear
support so that the cradles are free to move in the required direction along with
the launching girder while it is pulled at rear trolley for rotation.
Note: The cradles must be connected to each other by a suitable system so that their
c/c distance of 1.8m is maintained during rotation.
9. Remove the 100Ø vertical pin passing through the launching girder bottom
flange & the center of the top flange of top beam of rear trolley.
10. Lock the knuckle pins of rear trolley using 20 bars provided on its both sides.
11. Pull the launching girder in the require direction using macalloy bars provided
on the side face of top beam of rear trolley so that launching girder slides over
top beam to attain the required position.
12. Unclamp the anchor plates of longitudinal sliding bearing of middle support as
shown so that the Launching girder is guided by the rollers during further
auto launching.
(Refer sketch shown in stage 7 of auto launching)
Note: No auto launching shall be done after side shifting of the Launching Girder at
rear trolley
62
Step 2 Rotate the Launching girder vertically to ensure that acceptable heights at all
supports is achieved before anchoring the front support
Note: Refer detailed procedure for vertical rotation from annexure A.
63
64
STAGE - 11
Step 1 Open the telescopic leg of the front support so that the bottom beam of front
support rests over the concrete pedestal as shown in the drawing.
Step 2 Anchor the front support over pier cap by tightening anchor bolts in the
sleeves provided in the pier cap.
Note: Refer detailed procedure for lowering / raising of bottom beam/ telescopic leg
of front support from annexure C.
STAGE – 12
Step 1 Open the jacks of rear support & ensure that it experiences a minimum
reaction of 10tonnes (total reaction on four jacks) on it.
Step 2 Apply brakes at rear support using braking assembly provided at rear side of
the rear support.
Step 3 Tighten the vertical macalloy bars provided at top beam of rear trolley to
ensure that there is no possibility of relative movement between top beam of
rear trolley & launching girder during erection of next span.
Step 4 Move slider beams forward for the erection of next span as shown in the
drawing.
65
66
67
4.0 STAGES OF ERECTION OF SPAN
4.1 General
This section gives a general guideline for erection of precast segments in
various spans.
This section is divided in two parts.
4.3.1 This part gives a detailed description for erection of 31.0m span and
4.3.2 This part gives the sequence of erection of segments in all spans
assuming that the general procedure for lifting of individual segment shall
remain same as that detailed out for 31.0m span.
4.2 List of Drawings
Drawing no. Title
LG/15 Scheme for Erection of Precast Segments
(Sheet 1 of 2 & Sheet 2 of 2)
68
4.3.1 ERECTION PROCEDURE FOR 31.0M SPAN
STAGE – 1
Step 1 Move all the slider beams towards the span to be erected as shown.
Note: Only number of slider beams required for the erection of the span shall be
moved
CHECK LIST BEFORE ERECTION
1. All Supports are properly anchored with the span erected/pier cap.
2. Supporting jacks of middle & rear support are locked using lock nut provided
in the jacks.
3. Brakes are applied at middle support using braking assembly provided at their
rear side.
4. The Launching Girder is anchored to the top beam of rear trolley using four
no. macalloy bars provided.
5. Middle support cradles are anchored using the Macalloy bars provided over
the cross beam B1 so that it doesn’t move in transverse direction during
erection of precast segments.
69
70
STAGE – 2
Step 1 Position the trailer having precast segment S-1 between the spans to be erected
in such a manner that the center of segment to be erected lies as close as
possible to the fixed mounted hoist while looking at it from top of launching
girder.
Step 2 Attach the lifting beam hanging from the fixed mounted hoist to the
Temporary Prestressing beams attached to the segment at sofit level.
Note: Temporary Prestressing beams will be vertically stressed at casting yard
before its delivery at site for erection.
Step 3 Lift the segment slightly & rotate it to the required direction for erection.
Step 4 Lift the segment up to the required height i.e. maintaining a distance of 3.5m
between sofit of launching girder & the top of crown of the segment.
71
72
STAGE – 3
Step 1 Attach the suspenders through wire rope assembly of first slider beam to the
temporary prestressing beams at sofit level of the segment.
Step 2 Slightly lift the suspender by monojacks.
Procedure For Transferring The Weight of Segment From Hoist To Suspender Bars
1. Lift the suspenders by monojacks and transfer a force of not more than
0.5tonne per suspender in order to remove initial slackness in the suspender
bars.
2. Release the weight of segment from the fixed mounted hoist so that the weight
is transferred automatically on the suspenders of the slider beam.
Note: It shall be monitored that the slider beam remain in contact with both the flats
provided on top of the Launching Girder i.e. there is no uplift (uplift is an
indication of load getting transferred on one suspender slightly more than the
load getting transferred on the other).
In case of uplift, raise the hoist and release the suspenders and check the slider
beam and suspenders carefully for the possible reasons and rectify them and
then repeat the procedure 1 and 2.
3. After transferring complete load from the fixed mounted hoist to the
suspenders remove the pins connecting the lifting beam and the Temporary
Prestressing beams.
Step 3 Raise the lifting device (Lifting Beam) so that it does not obstruct the
movement of slider beam while the segment is shifted to its required position.
Step 4 Move the first slider beam along with the suspended segment to the position as
indicated.
73
Step 5 Line and level S-1 as per latest G.A.D. of Alignment for the concerned span.
Step 6 Lock the slider beam in this position using removable brackets provided for
locking (refer details from Drg. No. LG/04 and Sketch No. LG/SK-1).
Step 7 Secure the position of the segment by placing wooden packing in the gap
between segment and shear key.
74
75
STAGE – 4 TO STAGE – 6
Step 1 Repeat steps of stage 2 & stage 3 with segments S-1, S-2, S-3, S-4, S-5, & S-6,
one by one, so that the segments from S-1 to S-6 are erected as shown.
Note: The correct position / alignment of segments S-2 to S-6 shall be ensured by
dry matching S-2 with S-1, S-3 with S-2 and so on in the sequence of their
erection.
STAGE – 7
Step 1 Move remaining slider beams towards segment S-6 as shown.
STAGE – 8
Step 1 Lift the pier segment S-11 exactly in the same manner as the earlier segments
& position it with the respective slider beam as near to the shear key as
possible, as shown.
Note: Do not pack the segment S-11 with the shear key
STAGE – 9
Step 1 Lift the segment S-10 exactly in the same manner as the earlier segments &
park it over S-11 segment as shown.
Note: Maintain a minimum vertical gap of 100 mm between segment S-11 and S-10
76
77
78
79
80
81
82
STAGE – 10 TO STAGE – 11
Step 1 Lift the segments S-9 & S-8 & S-7 in the similar manner as done in earlier
cases & positions them as shown.
Step 2 Dry match segment S-6, S-7, S-8 & S-9.
Step 3 Lower the segment S-10 and dry match with the segment S-9
Step 4 Dry match segment S-11 with S-10
Step 5 Check the levels and alignment of span
Step 6 After ensuring correct alignment shift the segment S-11 and S-10 by 100mm
and 50mm respectively toward shear key
Step 7 Lift segment S-10 ensuring a vertical gap of 100mm (minimum) between
segment S-10 and S-11
Step 8 Shift segment S-2 to S-9 by 300mm toward S-11 so that a gap is created
between Segment S-1 and S-2 for gluing.
83
84
85
STAGE – 12
Step 1 Apply epoxy glue between segment S1 To S2
Step 2 Do Temporary Prestressing of the segments S-1 & S-2 by Macalloy Bars.
Note: After temporary prestressing a gap of 300mm will be automatically created
between segment S-2 and S-3.
Step 3 Repeat the step – 1 & step – 2 up to segment S-9
Note: Epoxy shall be applied on both surfaces to be bonded as per the instructions of
the supplier.
STAGE – 13
Step 1 Apply Epoxy glue on remaining segments i.e. surfaces between S-9, S-10 and
S-11 simultaneously.
Step 2 Lower the segment S-10 by vertical suspender of sliding beam and position it
close to segment S-9.
Step 3 Shift the segment S-11 close to segment S-10.
86
87
88
STAGE – 14
Step 1 Do Temporary Prestressing of segments S-9 To S-11 by macalloy bars one by
one.
Note: The entire procedure of lowering of segment S-10 and subsequent shifting of
S-10 and S-11 for closing the gaps and the Temporary Prestressing shall be
done with in the open time of the Epoxy adhesive to be used as per the
supplier’s manual for application of Epoxy adhesive.
STAGE – 15
Step 1 Insert Prestressing tendons and install their anchors.
Step 2 Do Longitudinal Prestressing of entire span.
STAGE – 16
Step 1 After Prestressing load is transferred on temporary bearings.
Step 2 Release the suspenders & remove the Temporary Prestressing beams.
Step 3 Move the sliding beams towards the counter weight side.
Step 4 Launching Girder is ready for Auto Launching.
89
90
91
92
4.3.2 ERECTION SEQUENCE OF PRECAST SEGMENTS IN DIFFIRENT SPANS
General procedure for lifting of segments remains same for all the spans. However in span of
smaller length, only number of segments and their sequence for erection changes.
Erection Sequence of Precast Segments For 31m Span
Total number of Segments = 11 (S1, S2, S3, S4, S5, S6, S7, S8, S9, S10, S11)
STAGES
1. Move 11 Sliding beams towards the Front support & Erect Segment S1
2. Erect Segment S2
3. Erect Segment S3
4. Erect Segment S4
5. Erect Segment S5
6. Erect Segment S6
7. Move remaining 5 Sliding beams towards the Segment S6 then Erect Segment S11 &
position it near shear key as possible
8. Erect Segment S10 & park Segment S10 over the Segment S11
9. Erect Segment S9
10. Erect Segment S8
11. Erect Segment S7
93
Erection Sequence of Precast Segments For 28m Span
Total number of Segments = 10 (S1, S2, S3, S4, S5, S7, S8, S9, S10, S11)
STAGES
1. Move 10 Sliding beams towards the Front support & Erect Segment S1
2. Erect Segment S2
3. Erect Segment S3
4. Erect Segment S4
5. Erect Segment S5
6. Move remaining 5 Sliding beams towards the segment S5 then Erect Segment S11 &
position it near shear key as possible
7. Erect Segment S10 & park Segment S10 over the Segment S11
8. Erect Segment S9
9. Erect Segment S8
10. Erect Segment S7
94
Erection Sequence of Precast Segments For 25m Span
Total number of Segments = 9 (S1, S2, S3, S4, S6, S8, S9, S10, S11)
STAGES
1. Move 9 Sliding beams towards the Front support & Erect Segment S1
2. Erect Segment S2
3. Erect Segment S3
4. Erect Segment S4
5. Move remaining 5 Sliding beams towards the segment S4 then Erect Segment S11 &
position it near shear key as possible
6. Erect Segment S10 & park Segment S10 over the Segment S11
7. Erect Segment S9
8. Erect Segment S8
9. Erect Segment S6
95
Erection Sequence of Precast Segments For 22m Span
Total number of Segments = 8 (S1, S2, S3, S4, S8, S9, S10, S11)
STAGES
1. Move 8 Sliding beams towards the Front support & Erect Segment S1
2. Erect Segment S2
3. Erect Segment S3
4. Move remaining 5 Sliding beams towards the segment S3 then Erect Segment S11 &
position it near shear key as possible
5. Erect Segment S10 & park Segment S10 over the Segment S11
6. Erect Segment S9
7. Erect Segment S8
8. Erect Segment S4
96
Erection Sequence of Precast Segments For 20.5m Span
Total number of Segments = 7 (S1, S2, S3, S6, S9, S10, S11)
STAGES
1. Move 7 Sliding beams towards the Front support & Erect Segment S1
2. Erect Segment S2
3. Erect Segment S3
4. Move remaining 4 Sliding beams towards the segment S3 then Erect Segment S11 &
position it near shear key as possible
5. Erect Segment S10 & park Segment S10 over the Segment S11
6. Erect Segment S9
7. Erect Segment S6
97
5.0 MANUAL FOR ERECTION OF FIRST SPAN
5.1 GENERAL
The erection of precast segments for the construction of superstructure
requires segments to be lifted by the Launching Girder, however while
erection of first span there is no permanent platform available for the
Launching Girder to stand, therefore a temporary structure is required initially
to support the Launching Girder for the erection of first span.
This section is an attempt to enumerate step-by-step procedure of erection of
Launching Girder for first and second span and the superstructure required for
the movement of Launching Girder.
To simplify the process detailed drawing sketches showing position of
launching girder and its accessories have been shown along with the detailed
step by step procedure.
5.2 LIST OF DRAWINGS
Drawing no. Title
215/LG/22 ERECTION SEQUENCE OF LAUNCHING
(SH. 1 OF 3 TO SH. 3 OF 3) GIRDER BETWEEN PIERS 122 TO 123
98
5.3 ERECTION OF LAUNCHING GIRDER IN FIRST SPAN
This section gives a series of sketches showing various stages of Launching
Girder and corresponding condition of erection of span.
The complete erection of Launching Girder includes erection of Launching
Girder and Three spans. It shall be understood that once the Launching Girder
is fully erected then it is capable of auto launching and erecting the spans in
continuation as explained is section 3 and section 4 of this manual.
The scheme has been covered in 23 Stages covering all possible conditions
encountered in the process.
Note: It is important to note that the scheme for Erection of Launching Girder
Between Piers 122 To 123 is specifically meant for erection of Launching
Girder between piers 122 to 123 and the same can not be applied as it is for
initial erection between any other pier combination for which detailed
drawings will be developed separately as and when required.
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
6.0 REFRENCES
Detailed manual of supplier for different items shall be referred for their
operation
123
Annexure A
PROCEDURE
FOR
VERTICAL ROTATION
124
A.1 GENERAL
For spans with no change in gradient the vertical rotation is not required so
that the height of various support shall be 3.5m each measured from top of
crown of the segment to the bottom of Launching Girder.
Note: Height front support will be 5.2m from top of pier cap to bottom of Launching
Girder.
For change in gradient following procedure shall be followed.
125
A.2 Detailed description of various conditions of launching Girder in vertical
grade & corresponding height adjustment of its supports
Direction of Launching
Front Middle Rear RearSupport Support Support Support
Grade g1% 5.6m Grade g2% Grade g3%
Span to be Erected Newly Erected Span
A.2.1 Down Grade
The Launching Girder is said to be moving on down grade if > 0 or grade g 1% < g 2%
(with +ve / -ve signs considered)
Procedure
1. Reduce the height of middle support & try to achieve the required height at
Front Support.
Note: The minimum height to kept at middle support shall be 3.4m however in odd
conditions it can be reduced to 3.35m.
2. If the required height is not achieved raise the height of rear trolley.
126
A.2.2 Up Grade
The Launching Girder is said to be moving on upgrade if < 0 or grade g 1% > grade 2%
(with +ve / -ve signs considered)
Procedure
1. It is required to reduce the height of rear trolley however during auto
launching the Height of rear trolley has to be kept 3.5m deliberately which
happens to be its minimum possible height therefore this operation in not
required.
2. Raise the height of middle support to achieve the required height at front
support.
A.3 Permissible range of height to be ensured at front support
Minimum height* - 3.35m (measured from top of crown of the segment to the bottom of
Launching Girder)
Or 5.05m (measured from top of pier cap to the bottom of Launching
Girder)
Maximum height** - 3.7m (measured from top of crown of the segment to the bottom of
Launching Girder)
Or 5.4m (measured from top of pier cap to the bottom of Launching
Girder)
*Minimum height for inserting middle support during further auto launching
**Maximum length of suspenders available for erection of segments
127
A.4 Calculation Of Height At Front Support For A Known Height At Rear
Trolley And Middle Support
A.4.1 Down Grade
Assuming following data for sample calculation
Span to be erected = S1 = 25m
Span already erected = S2 = 25m (over which Launching Girder is resting at Present)
Grade g1 = + 1.3% (The height of structure is increasing in the direction of launching)
Grade g2 = + 2.4% (The height of structure is increasing in the direction of launching)
Grade g3 = + 2.5% (The height of structure is increasing in the direction of launching)
Grade g1% < Grade g2% therefore the launcher is moving on down grade
Height at rear trolley = 3.5m (assumed)
Height at middle support = 3.4m (assumed)
Distance between middle support & rear trolley
= 64.75 - *4.45 - **2.5 - ***(25 + 1.8)
= 31.0m
*Cantilever Distance beyond center line of rear trolley
**Cantilever Distance ahead center line of front support
***Distance between center line front support & middle support
128
Grade of Launching Girder
Top of Crown of Segment
Newly Erected
Span
Bottom of
Launching Girder
Direction Span to be
Of Erected
Launching
a
b
c
d
X
0.9m
0.9m
CL Pier
CL Pier
CL Pier
FrontSupport
MiddleSupport
RearTrolley
Grade g1%
Grade g2%
Grade g3%
129
a = [ 31 - ( 25 - 0.9 ) ] x 2.5 = 0.1725m
100
b = ( 25 - 0.9 ) ] x 2.4 = 0.5784m
100
c = Height of Middle Support – (Height of Rrear Trolley – a - b)
= 3.4 – (3.5 – ( 0.1725 ) – ( 0.5784 ))
= 0.6509 m
Grade of Launching Girder = 0.6509 X 100 = 2.09968%
31
Height of Front Support
X = Height of Middle Support – D + ( Span + 1.8 ) x Grade of Launching Girder
100
d = 0.9 x Grade g2 + ( Span ) x Grade g1
100 100
= 0.9 x ( 2.4 ) + ( 25 ) x ( 1.3 )
100 100
= +ve 0.3466m
x = 3.4 – ( 0.3466 ) + ( 25 + 1.8 ) x ( 2.09968 )
100
= 3.616m > 3.35m & < 3.7m ok
Height of Front Support = 3.616m
For Height at Middle Support = 3.400m
And Height at Rear Trolley = 3.500m
On the same lines the heights at front support, middle support & rear trolley can be
calculated for any span.
130
A.4.2 Up Grade
Assuming following data for sample calculation
Span to be erected = S1 = 25m
Span already erected = S2 = 25m (over which Launching Girder is resting at Present)
Grade g1 = - 1.3% (The height of structure is decreasing in the direction of launching)
Grade g2 = - 2.4% (The height of structure is decreasing in the direction of launching)
Grade g3 = - 2.5% (The height of structure is decreasing in the direction of launching)
Grade g1% > Grade g2% therefore the launcher is moving on up grade
Height at rear trolley = 3.5m
Height at middle support = 3.6m (assumed)
Distance between middle support & rear trolley
= 64.75 - *4.45 - **2.5 - ***(25 + 1.8)
= 31.0m
*Cantilever Distance beyond center line of rear trolley
**Cantilever Distance ahead center line of front support
***Distance between center line front support & middle support
131
Grade of Launching Girder
Top of Crown of Segment
Newly Erected
Span
Span to be
Bottom of Erected
Launching Girder
Direction
Of
Launching
a
b
c
d
X
0.9m
0.9mFrontSupport
MiddleSupport
RearTrolley
CL Pier
CL Pier
CL Pier
Grade g1%
Grade g2%
Grade g3%
132
a = [ 31 - ( 25 - 0.9 ) ] x ( -2.5 ) = -0.1725m
100
b = ( 25 - 0.9 ) ] x ( -2.4 ) = -0.5784m
100
c = Height of Middle Support – (Height of Rrear Trolley – a - b)
= 3.6 – (3.5 – ( -0.1725 ) – ( -0.5784 ))
= -0.6509 m
Grade of Launching Girder = -0.6509 X 100 = -2.09968%
31
Height of Front Support
X = Height of Middle Support – D + ( Span + 1.8 ) x Grade of Launching Girder
100
d = 0.9 x Grade g2 + ( Span ) x Grade g1
100 100
= 0.9 x ( -2.4 ) + ( 25 ) x ( -1.3 )
100 100
= -ve 0.3466m
x = 3.6 – ( -0.3466 ) + ( 25 + 1.8 ) x ( -2.09968 )
100
= 3.384m > 3.35m & < 3.7m ok
Height of Front Support = 3.384m
For Height at Middle Support = 3.600m
And Height at Rear Trolley = 3.500m
On the same lines the heights at front support, middle support & rear trolley can be calculated
for any span.
133
Annexure B
PROCEDURE
FOR
MOVEMENT OF
MIDDLE SUPPORT / REAR SUPPORT
USING MOVING TROLLEY
134
135
136
137
Annexure C
PROCEDURE
FOR
RAISING / LOWERING OF
TELESCOPIC LEG / BOTTOM BEAM
OF FRONT SUPPORT
138
139
140
141
REFER AUTOCAD FILEREFER AUTOCAD FILE
FOR SKETCHESFOR SKETCHES
ON BLANK PAGES OF THE BOOKLETON BLANK PAGES OF THE BOOKLET
142