Q.No. 1 Describe the method of taking up mechanized renewal of PSC sleepers in compound curve in electrified track circuited SWR track.
Ans : Mechanized renewal of PSC sleepers can be taken up either by PQRS or by TRT- By PQRS – At site – Pre block activities-
1. Linking of auxiliary track to connect line and level will be required.
2. Lubrication of bolts in fishplates joints of SWR track to be done in advance.
3. Recoup all fittings in PSC sleepers.
4. Remove U/s sleepers and joggle fish plate and wooden blocks after imposing speed restriction. Also remove S&T fittings and OHE earthing strips.
5. If required the SE of track can be modified under SR to facilitate lifting of panels by PQRS. At Base Depot-
1. Sufficient P-Way materials like PSC, fittings, lubricants etc and T&P with portal cranes to be arranged.
2. Pre-fabrication of panels by standard service rails at required sleeper density to be done.
3. Loading of Pre-fabrication panels on to the PQRS rake and proper marshalling of rake with empty wagons, machine wagon and staff rest van etc.
At site – During block activities-
1. Removing of fish plates and cutting of rails to make panels of adequate length for lifting by PQRS portal cranes.
2. Loading of panels from track on PQRS rake and laying of fabricated panels in track with proper line and level on prepared ballast bed.
3. All S&T and OHE fittings will be restored. Post block activities-
1. Ballasting, boxing, aligning and packing of tracks (At least four rounds by ON Track tampers) to relax speed restrictions.
2. Welding of rail joints and correct setting of gaps in SWR track. By TRT- At Base Depot-
1. Loading of PSC and marshalling to form proper rake.
2. Loading of new fittings in fittings wagon At site –
Pre block activities-
1. Lubrications of all fittings to release jammed ERC.
2. Easement of SE if required for working of TRT .
3. Removal of joggle fish plates, wooden blocks, rail pegs, S&T fittings, OHE earthing strips.
At site – During block activities-
1. Six PSC at the start of work will be removed to lower sled/plough.
2. TRT will pick up old PSC from track and load it on conveyor from where portals will load them on empty BFRs. Also new PSC from BFR will be loaded on Conveyors and laid in track at required sleeper density
3. All S&T and OHE fittings will be restored. Post block activities-
1. Ballasting, boxing, aligning and packing of tracks (At least four rounds by ON Track tampers) to relax speed restrictions.
2. Welding of rail joints and correct setting of gaps in SWR track.
Q.No.2 .Describe with sketch the signages to be provided at manned and unmanned levelcrossings for both train drivers and road users.
Q.. 3).Describe with sketch the correct placement of indicators for a track renewal site in site in
suburban section for both single line and double lines?
d. Obtain the signature of the station master/block Hut-in-charge on duty at the station/Block concerned for his arrival and departure and exchange patrol books with adjacent patrolmen.
d. Exchange the reports as to the conditions on their beats with adjacent patrol men and statio watchmen on the way.
d. Heed instructions from driver who may report a condition of danger at a kilometrage proceed to the place indicated and take necessary measures.
(2) it is of supreme importance that patrolmen and watchmen thoroughly understand what they hav do in the event of emergency. Every effort should be made to instruct and drill the men in t duties. In the even of an emergency the patrolmen should devote their whole time and energ the protection of the line and summoning of assistance. Having protected the line and summ assistance, they should resume their patrolling.
Q.No.7 EXPLAIN TRACK RENEWAL WORKS BY PQRS AND TRT TRACK RENEWAL MACHINES IN LWR TERRITORY WITH MINIMUM SPEED RESTRICTIONS. LWR territory with minimum speed restrictions Track renewal work by PQRS:-
Base depot on PQRS to prepare prefabricated panels. The following preparatory works before renewal shall be done. Foot by foot, survey id done to collect information about ballast requirement, lifting of
track and depth of deep screening required.
I. Final rail levels should be paint marked on OHE masts or level pegs should be provided.
I. Realignment of curves, of necessary.
I. Deep screening of track in advance of sleeper renewal.
V. LWRs to be distressed at proper temperature and converted to panels. ( multiple of sleeper spacing).
V. Impose speed restriction of 20 kmph before starting the work.
I. Auxiliary track is linked with service/new rails.
I. Opening of ballast
I. Recoupment of missing fittings (keys & cotters etc. for CST-9 sleepers)
X. Oiling & greasing of bolts.
EXECUTION OF RENEWAL
I. Under traffic block relaying train is taken to block section. Portal cranes are unloaded on A.T. I. A.T. should be laid in advance at the place of working.
I. Fish plate gang goes well ahead of portal crane removing fish plates for 5-6 rail lengths.
V. Assuming 2 portal cranes are available, the portal cranes are positioned at the centre of first & second rail panel to be lifted. The rail grippers are lowered. They should be in alignment with rail head at 4 points. First & second panels are lifted up and cranes move towered the PQRS train. The released panels are unloaded centrally on empty BFRs.
V. Similarly 2 more panels 3rd &4th are lifted and unloaded on empty BFR. I. Ballast is leveled up manually to correct level. It is desirable to use template.
I. On return 2 preassembled panels are lifted from loaded BFRs, cranes move and place at position (1) & (2) in correct alignment.
I. 5th & 6th panels of old track are lifted and operations repeated.
X. In the last, new panels are placed to close the gap at predetermined point depending on block duration.
X. Fish plate gang fixes the fish plates on newly laid panels. The new panels should be properly matched in the base depot, otherwise adjustment of the rail gap at joints of newly laid panels will be required. At the closing point insertion of rail closer will be required.
I. Ballast is inserted below sleeper seat and kuttcha packing is done with showel. TRT can work in following these modes-------
I. Complete track renewal.
I. Replacement of sleepers.
I. Replacement of rail.
A. Base Depot--- a. Base depot for TRT working shall be centrally located in working area of 30-40 kms,shall have the facility of water, electricity, communication and accommodation for machine & P.way staff.
b. Provide sufficient stock of new sleeper, ERCs/ fastenings, liners, rail pads in the base depot.
c. 30 Nos. modified BFRs/BRHs shall be required for one set of TRT (10 Nos. for 1600 sleepers + 1 empty & remaining for rectifying supply & dispatch of released material ). Wooden battens of 75*75 mm shall be provided between two layers on the outside of MCI inserts.
d. Loadfastening s like ERCs, liners and rail pads as required during block.
B. Preparatory arrangements in the field.
a. Sleepers shall be checked for their condition. All corroded broken / steel / cst-9 sleepers shall be marked. Foot by foot survey shall be carried out to identify the locations having lateral or longitudinal infringements within one metre of sleeper ends like creep posts, alignment posts etc.
b. Availability of adequate ballast before relaying shall be ensured foe tamping and restoration of speed at the earliest.
c. Deep screening shall be carried out in advance, excess ballast removed 7 shoulders brought down to sleeper level. Consolidation of ballast bed shall be ensured.
d. Check rails at level crossing falling in the working range shall be removed in advance.
e. All longer fish plates / joggled fish plates clamps and wooden blocks etc. shall be removed from the working range.
f. New rails shall be unloaded paired, fish plated or welded in one piece as required foe day’s work and set around 1.5m from centre of track. Rails shall be kept o for with adequate support to avoid shifting during working of TRT.
g. In case of CST-9 sleepers all reverse jaw sleepers shall be removed or their lip may be cut by lip cutter and gauging done.
h. Interlaced sleepers if any having difference in height shall be removed.
i. Ensure easing out of fitting s/fastenings.
j. Seven wooden sleepers shall be laid in track out of which 5 sleepers behind the rail cut and ballast around them removed for easy lowering of plough.
k. Walkie - talkie sets for communication should be available with engine driver, JE/SE (P.Way), machine staff and adjoining stations.
l. Ensure availability of S&T and OHE staff ( in electrified section) for removal and bonding back including earth bonding of new rail panels where required.
m. Replace 2 rail lengths of existing PSC sleeper with wooden.
n. Existing track shall be distressed at 100C below the maximum temperature likely to be attained during the work if the rail temperature falls beyond td-200C +100C
C. Sequence of Operations-----
• TRT is stopped at site in a position that side plough is on first of cut rail
• Shoulder/side plough is lowered.
• Remove 3.40 m long rail closure.
• Lower sled from beam car on to the rail seats of rail closure.
• Bring idle bogie of handling car on to the sled and lock up (by bringing back the machine)
• Slew out old rail and move TRT ahead so that sled clears rail closure portion.
• Remove the old sleepers manually from the closure area and level the ballast bed.
• Old sleeper pickup wheel & dynamic plough are lowered in space cleared by removal of old
sleepers.
• Rail ends of preceding day’s work shall be connected to the new rail laid on the sleeper
shoulder
• Start removing old sleepers by pick up wheel.
• Set CAM wheel on to the rail and commence laying of new concrete sleepers by advancing
the machine by automatic mode.
• As TRT moves ahead old rails are threaded out and new rails are threaded in with the help of
5 pairs of guiding rollers provided all along the length of TRT.
D. Operations during block---
• Ensure proper protection at work site, lookout and hooter in proper working order to give
warning or train approaching on the adjacent line.
• Take power block if staff is required to climb on the top of machine for repairs in case any
breakdown.
E. Post Block operations----
• Ballasting of track shall be done immediately after relaying.
• Ballast regulator, tie tamping machine and dynamic track stabilizer shall be deployed to
enable restoration of speed at the earliest.
• In- situ welding of isolated joints shall be done to convert the track in LWR/CWR.
• SEJs shall be provided at locations as per approved LWR/CWR plan. TRT is used for track relaying works. The CTR/TSR can be done by TRT.
Before introducing TRT for track renewal works, there are some pre- requisite before deployment of any machine in section, which are as under—
Pre-Tamping operation & the following temporary shall be completed before undertaking work---
i. Field survey should be carried out to determine existing profile of track and to decide the general lift. In case of design mode working, the survey should be done as per guidelines.
i. The beginning and the end of curves/ transition curves should be marked on sleepers.
Super- elevation and slew should e marked on alternate sleepers to act as guide for the operator.
i. Low cess should be made-up. v. Track drainage should be improved for better retentivity of packing . pumping locations should be attended. Rounded ballast should be replaced with clean and angular ballast. v. Deficient fittings and fastenings should e made food and all fittings and fastenings like fish bolts. Keys, cotters, loose jaws elastic rail clips, pads etc. should be properly tightened. Worn out fittings should be replaced. i. Broken and damaged sleepers shall be replaced.
ii.Distressing of rails, adjustment of creep, expansion gaps in joints, buffer rails and SEJs etc, if necessary, shall be carried out.
Q.8. What precautions should be observed while unloading a Ballast DMT in the section?
Answer: - 1) SSE/P.Way/ Incharge should supervise unloading of Ballast DMT personally.
2) Sufficient trained departmental personnel along with blacksmith must be deputed for unloading of Ballast.
3) Ensure timely examination of Ballast hoppers by TXR.
4) Before unloading of DMT, doors of all hoppers must be checked & released. There should be no Jamming of doors.
5) Brake power must be checked by Driver and the DMT should be manned by a Guard.
6)Proper planning for unloading of Ballast hoppers TP wise should be done by PWI in advance and clear signal should be shown to drivers to stop at exact required locations.
7) PWI must explain and brief the mate, keyman, Driver and Guard about the location and safe
working of DMT.
8) Door flaps of Ballast hoppers should be opened slowly to avoid sudden discharge and heaping of ballast.
9) PWI must move along with the DMT while ballast is being unloaded and instruct the staff on DMT as per need.
10) Do not move DMTs at speeds higher than 8 to 10 kmph while unloading of Ballast.
11) DMT shall move only in one direction and no pushing back should be done.
12) Do not stop DMT while unloading is in process.
13) Do not move DMT if it has stopped to any reason without ensuring clearance of ballast from
track.
14) Ballast should not be unloaded on and near Level X-ings, points and crossings and Girder bridges.
15) Do not work DMTs after sunset and on foggy days.
16) Uneven unloading must be avoided.
Q.No.9. Describe working of TRT with requirement of yard, loading/unloading of sleepers, marshaling of rake to achieve optimum out put. Also mention benefits over renewal with PQRS.
Ans. Pre work for TRT working –
1. Removal of crib ballast 4 to 5” from top of sleeper
2. Fitting should not be jammed.
3. All the broken sleepers should be removed/replaced in advance.
4. Any lateral obstruction min 50cm from the end of PRC to be removed.
5. Electrical/S&T/Water pipes etc buried under the ballast or sleeper upto 6” to be protected to facilitate complete renewal
6. Long size fish plate bolts/joggle plate removed.
7. SEJ falling in length should be replaced with rail.
8. During night halogen at interval of 30m in operator side and in the length of work to be targeted plus the length of rake should to provided. Stand by generator should be available.
9. OHE & S&T staff should be informed well in advance.
10. Gas cutter should be available at site.
11. It should be ensured that all 4 dowels and 2 locks of each rail bridge are available. Just before block-
1. Caution of 20 KMPH should be imposed at TSR site to be renewed by TRT.
2. After imposing caution at TRT site a hacksaw cut should be made in advance and a gap of 10mm should be created in fish plated joint.
3. Cut should be 40 sleepers away from fixed location
4. 07 sleepers opening upto bottom of PRC to be done.
5. Alternative ERC should be removed before block. During block period- TRT is a system for complete mechanisation of trak renewal process. It does the following jobs :-
a. Threads out old rails from track.
b. Removes old sleepers.
c. Levels and compacts ballast bed.
d. Places new sleepers.
e. Threads in new rails into track.
f. Driving of ERC in following of TRT block is done manually or by clip applicator.
Progress of TRT-
1. Progress of TRT is 600 Nos. PRC sleepers/Eff hours. After block activity-
1. Gas cut if any should be replaced immediately with new rail hacksaw cut.
2. Boxing of ballast is to be done.
3. Speed can be raised upto 40 KMPH immediately after block if no gas cut existing. Requirement of yard in TRT Depot
1. Minimum three tracks should be available in TRT Depot, One separate track should be available for TRT and other associated machines and their rest vans.
2. Layout should be so that there is no block of running lines while shunting.
3. For loading/unloading of PRC sleepers gantry should be provided on two lines/three lines.
4. Auxiliary track should be there for running of gantry.
5. There should be one office cum store in yard and emergency control phone should be there.
6. Space should be available for stacking new/release PRC sleepers.
7. Road approach should be available for loading of new/SH PRC sleepers.
8. Lighting arrangement should be there for night working.
9. Drinking water arrangement should be available for staff.
10. As far as possible TRT yard should be made in middle of relaying stretch.
Loading of sleepers-
1. Loading of PRC sleeper should be done by gantry/portal crane.
2. Floor of BFR should be free from ballast.
3. Wooden batten 75mmx75mm in full length of 20 PRC sleepers be used.
4. Each layer should consist of 20 PRC sleepers.
5. Loading of PRC sleepers should not be eccentric.
6. Special type BRN, in which rail must be fixed on the BFR’s for loading of first layer of
sleeper.
Unloading of sleepers-
1. Unloading of PRC sleepers should be done by gantry/portal cranes.
2. Sorting out of SH/US PRC sleeper should be done just after unloading before stacking.
3. SS sleepers should be stacked separately and U/S sleepers should be stacked separately.
4. Disposal of SS/US PRC should be done as soon as possible to make sufficient room for
further incoming sleepers.
Marshalling of rake to achieve optimum output-
1. After block release sleepers, BRN must be sorted out otherwise it will waste time of gantry of TRT for leading of PRC sleepers.
2. Next to TRT, ½ BRN should be kept empty to keep starting release sleepers then sequence of lifting new PRC/putting release PRC will build up automatically.
3. Planning for quantity of TSR with TRT in particular block should be done in advance and according to that, number of BRN loaded with PRC should be attached with rake.
4. Quantity of TSR with TRT will depend upon
(a) Duration of block/probable extension of block
(b) Stretch of last block. Benefits over renewal with PQRS-
1. There is no need to prefabricated panels.
2. No auxiliary track is to be laid at site.
3. Concrete sleepers loaded on modified BRNs are directly taken to site and relayed one by
one.
4. Existing track rails not required to be cut in length of 13.00 mtr.
5. New rails unloaded at site on shoulders and duly pairs or fish plated are replaced with old
rails along with sleeper renewals.
6. The quality of track produced by TRT is very good and the traffic is allowed at 40 KMPH just after relaying.
Q.No.10. Describe scheme for combined mega blocks for maintenance of busy yards with coordination of other departments i.e. S&T, TRD, Electrical.
Ans. SELECTION OF SITE/LOCATION OF MEGA BLOCK –
1. Site for mega block should be so selected that only one line UP/DN may blocked.
2. Meticulous planning should be done by all departments to obtain maximum out put.
3. Each activity by each department should be planned.
4. Material and machinery should be locationed nearest to the work place.
5. Sufficient staff should be nominated for every location.
6. Effective lighting arrangement should be made for night working
REQUIREMENT OF P.WAY
1. Each site of mega block of busy yard must be supervised by separate JE/SSE. Request to ADEN/Sr.DEN to be submitted to arrange additional JE/SSE from adjoining section as per requirement.
2. Sufficient labour for each site should be arranged.
3. If blacksmith work involves, separate blacksmith should be arranged.
4. Mini store in Tata/small truck should be arranged having all P.way small fittings and after bock release could also be loaded.
5. Communication system should be effectively working.
Q.No.11 (i).Planning of various maintenance activities in current scenario after entry of new
track maintainers.
(ii) Use of small track machines.
Ans (i) PLANNING OF VARIOUS MAINTENANCE ACTIVITIES IN CURRENT SCENORIA AFTER ENTRY OF NEW TRACK MAINTAINERS.
1. Initial training of new trackmen should be got done as early as possible after joining of
new trackmen.
2. All uniform summer/winter should be given to new trackmen just after joining.
3. Work of maintenance should be so distributed that one new and one old trackman could perform the work simultaneously.
4. New trackman should not be deployed individually on safety location such as gateman banner flag, Trollyman etc.
5. New trackman should not be deputed as single Hot weather patrolman/cold weather patrolman.
6. Safety quiz and safety seminar should be organised at the regular intervals to counsel the new entrants. They should be counselled for personal safety also.
7. New trackman are more qualified. They should be encouraged to adopt small track machines for better result with less efforts.
8. The staff should be motivated to accept the safety precautions in religious manner.
Ans (ii) USE OF SMALL TRACK MACHINES Due to growing traffic and introduction of heavier track structure, faster and more efficient methods of maintenance are needed to be evolved. In the changed socio-economic scenario, role of small track machines has increase for quality maintenance of track. Different types of small machines have been developed for various activities on track. These small track machines are to be used for day-to-day maintenance, laying and construction of track. Based on field experience. Following machines are extremely useful –
1. Abrasive rail cutter
2. Rail cutting machine (saw type)
3. Rail drilling machine
4. Double action weld trimmer
5. Rail profile weld grinder
6. Portable DC welding generator
7. Toe load measuring device
8. Chamfering kit
Qus.12. Assembling & Laying of fan shaped pts & crossing by T-28 machine with quality.
Ans:-
Assembling:
a. Ensure the availability of all fittings at site strictly as per requirement of latest drawings for switch portion, lead and crossing portion.
b. The complete turnout will be assembled on a level ground adjacent to the site of laying or on the loop line connected to turnout.
c. Red/blue rounded marking on the sleepers should invariably be kept on the right hand side irrespective of left hand or right hand turnout.
d. Spacing of sleepers should be strictly as per layout drawing.
e. The sleepers shall be perpendicular to the straight track in switch portion only.
f. In lead portion the sleeper will be inclined at half the angle between the normals to straight and curve track at that point. Proposed disposition is appended.
g. To ensue correct layout laying of sleeper falling at transition from switch to lead and lead to crossing portion should be paid special attention sleepers in the switch portion lead portion and crossing portion are as under:-
h. The spacing of the sleepers in the lead portion should be as per layout drawing to make a radial or fan shaped layout. the spacing has been worked out separately for both the rails. The separate spacing on two rails make the layout far shaped in lead portion. h. The sleeper in the crossing portion shall be perpendicular to bisecting line of crossing. h. Sleeper no 3&4 may be placed for housing motor with the extended portion of sleeper in reverse direction only in circumstances where it cannot be avoided.
h. The approach sleeper in advance of switch portion should be provided without fail, they are for gradual elimination of slope of rail top(1:20) h. The exit sleeper behind the crossing portion should also be provided for gradual introduction rail slope(1:20) Site preparation for laying:- a. The site preparation to be competed well before laying turnout ensuring deep screening of ballast in turnout length and 30m on either side along the track. b. All jammed fitting to be ease out.
Laying : By T-28 Machine:- I. Take the appropriate traffic block and do the track protection. II. S&T staffs allow to disconnect the gears and the same time dismantling of xing and leads to be done. III. After dismantling materials to be kept in safe distance. IV. After dismantling work. The ballast/ground should perfectly levelled, variation in level may affect the gauge adversely. V. T-28 machine allowed to laying the assembled P&C. VI. Ensure proper alignment of P&C VII. Both ends to be connected. VIII. Kutcha Packing of newly assembled track to be done and allow the traffic with restricted speed. Ensure parameters of track as per manual
Q No. 13 a. What is pre-stressed concrete structures b. Explain advantages & disadvantages of pre-stressed concrete. c. Describe the details of mix design and design M-40 grade concrete.
a. What are pre-stressed concrete structures?
Pre-stressing cab be defined as the application of a predetermined force or moment to a structural member in such a manner that the combined internal stresses in the member resulting from this force or moment and from any anticipated condition of external loading will be confined within specific limits. In general, pre-stress involves the imposition of stresses opposite in sign to those which are caused by the subsequent application of working loads. For example, pre-stressing wires placed eccentrically in simple bam produce in the concrete an axial compression and hogging moment. Under service loads the same beam will develop sagging moment. Thus, it is possible to have the entire section in compression when service loads are imposed on the beam. This is the main advantage of pre-stressing concrete. It is well known that reinforced concrete cracks in tension. But there is no cracking in the pre-stressed concrete since the entire section is in compression. Thus, it can be said that pre-stress provides a means for the most efficient use of concrete. The basic principles and mathematical equations used in the analysis and design of pre- stressed concrete flexural members are same as those used for the reinforced concrete members. Though the form in which the relationships appear in a discussion of pre-stressed concrete may different to facilitate their application.
a. Explain advantages & disadvantages of pre-stressed concrete.
The most significant feature of pre-stressed concrete is that is free of cracks under service loads and enables the entire section to take part in resisting moments. Pre-stressed concrete is more predictable than ordinary reinforced concrete in several respect. Once concrete cracks, the behavior of reinforced concrete structures become quite complex. Since there is no cracking in pre-stressed concrete, its behavior can be explained on a more rational basis. In pre-stressed concrete structures sections are much smaller than those in reinforced concrete structures because dead load moments are neutralized by the pre-stressing moments and shear stresses are reduced. Other features of pre-stressed concrete are its high ability to resist impact, high fatigue resistance and high live load carrying capacity. It is possible to assemble precast pre-stressed elements thus saving cost shuttering and centering, and time besides maintaining a high quality control. Pre-stressed concrete construction has become extremely useful in the construction of liquid retaining structures and nuclear power reactors where absolutely no leakage is acceptable. This technique is of great value in railway sleeper, large span roofs.
Some of the disadvantages of pre-stressed concrete construction are as follows:
a) Is uses high strength concrete and steel,
b) It requires and anchors and bearing plates,
c) It may require complicated form work,
d) Labor cost may be greater, and
e) It requires a better quality control.
Yet there is an overall economy in using pre-stressed concrete construction as the decrease in member section results in the decrease in design loads and an economical substructure is required.
Concrete mix design is the step by step procedure to define the proportions of various ingredients of concrete (cement, flyash, water, aggregate, admixtures). The fundamental requirement of a concrete mix is that it should be satisfactory both in the fresh as well as in the hardened state, possessing certain minimum desirable properties like workability, strength and durability. The design should accommodate locally available materials in the best possible way without sacrificing the quality of the final product. There are various methods available which are developed by research institutes for the design of concrete mixes. The Bureau India Standards has also framed a standard (IS 10262-1982) Recommended Guidelines for Concrete Mix Design which has recommended procedure for design of concrete mixes for general type of construction using concreting materials normally available.
d. Describe the details of mix design and design M-40 grade concrete.
Target mean strength
= FCK+ TXS
TMS= 40+ 1.65X5
=48.25 Say 49 MPA
W/C Ration
Suppose the exposure conditions is – severe than minimum cement
Content = 320kg/cum
W/C ration = 0 .45
And minimum grade = M-30 where as we are designing for M-40 Gd. Hence safe
Now as per IS-10262-1982 water cement ration for 49 MPA concrete = 0.04
20mm size Aggregate: analysis MAS-20
Sieve size % passing
20mm 88%
10mm 3.5%
4.75mm 0.6%
Suppose the ration of irregular gravel & crushed agg.
= 70% = 30%
Now analysis of 10 mm size agg.
Sieve size %passing
10mm 77% 4.75mm
17% 2.36mm 6.6%
Suppose Irregular gravel:
crashed gravel 70% : 30%
Sand analysis Sieve size %passing
20mm 95%
10mm 91% 4.75mm
86% 600m 55%
In this analysis pure sand = 86%
And 600m passing = 55x100/86= 63.95, say 64%
Suppose the sand shape irregular:
rounded 50% : 50%
According to D.O.E method (department of environment )
Recommended proportion of fine agg. For percentage passing 600 micron sieve 9 (MAS- 20MM) for 60mm to 180mm slump.
As per experimental date
The percentage of sand at 0.4 water cement ration in MAS-20MM concrete will be as under For 60 % sand passing through 600M,
Seive,the ration of sand to be mixed in concrete = 35% and for sand in which 600M passing,sand is 80% than the ration of sand in the concrete to be taken 30%
Hence in 64% 600m passing sand the ration of fine aggregate in the concrete to be taken 34% Now F.A ; CA 34 : 66% The CA is further partning as CA-I (MAS-10M) CA-II (MAS-20)
Proportion of coarse aggregate. In MAS 20MM concrete The ration of CA I & CA-II 10MM : 20MM 33% : 67% 66% : 67% of 66% 22% : 44%
Ratio of aggregate. Sand CA-I CA-II 34% 22% 44% +6% -3% -3% 40% 19% 41% DO 10 mm -3 +30
Final ratio 37% 22% 41% A/C ration for the Mix of sand = 37% 20mm= 41%
10mm = 22% Suppose that the actual specific gravity of coarse agg. & fine Agg = 2.67.
Than A/C ration for medium workability = 4.1 Hence for 50Kg
cement Agg. = 50x4.10 = 205 kg Sand 10mm
20mm 37% 22% 41%
=75.85kg 45.10kg 84.05 kg
Water = 20kg Cement 50kg.
Again if suppose there is 3% moisture in sand 2.27 Kg water is available in 75.85kg sand Therefore putting correction in sand & water Qty.
Cement = 50kg
Water = 20-2.28= 17.72kg Sand = 75.85 + 2.28 = 78.13 kg
10mm size aggregate. = 45.10 kg
20mm size aggregate.= 84.05 kg
Q No:- 14. a. Explain criteria for Rail Renewal b. Explain pre temping and post temping attentions.
a) Criteria for Rail renewals
The following criteria have been prescribed for rail renewals:-
1. Incidence of rail fractures or rail failures
2. Wear of rails
3. Maintainability of track to the prescribed standards.
4. Service life of rails
5. Services life of rails 6. Plan based renewals These will be discussed in detail in subsequent paras.
i. Incidence of rail fractures/failures This factor which involves safety should have over riding priority while deciding rail renewals. A spate of rail failures on a particular length may necessitate rail renewal. In such cases ultrasonic testing of rail should be done and the results of such testing taken into consideration. If the rail failures are high on a section 4% in a year or 10% the section should be considered for rail renewal.
ii. Wear of rails: - rail renewals may become necessary, because of excessive wear.
The following different criteria have been laid for the same:-
a) Limiting loss of section
b) Wear due to corrosion
c) Vertical wear
d) Lateral wear
iii. Maintainability of track to the prescribed standards. There may be cases where though the service life of a rail has not yet reached, yet due to local factors like curves, steep gradients, high speeds, heavy axle loads, burrs, scabbing, wear
of rails etc. renewals become necessary due to following considerations:-
a) Poor running quality of track in spite of extra maintenance labour engaged on the section.
b) Disproportionate cost of maintain the track in safe condition.
c) Poor condition of rail due to hogging, battering, scabbing, wheel burn, and other conditions such as excessive corrugation of rail etc. as can be ascertained by visual inspections and which make the track maintenance difficult and uneconomical and affect the running quality of track.
iv. Service life of rails
a) Due to the passage of moving loads, alternating stresses are created in the rail section. The number of reversal of stresses is directly related to gross million tones carried by the rails. Majorituy of rail fractures originate formthe fatigue cracks, which depend on the total G.M.T. carried. The track is considered for renewal after it has carried threshold GMT.
b) Sleepers are considered overdue renewal when they have completed service lie as follow
us:- Wooden ........................... 10 years ST & CST-9 ...................20 years for A, B, C routes and 25 years on D & E routes.
c) The condition of rails and sleepers is the ultimate criteria for track renewal.
v. Plan based renewals: - Renewals to pre-determined plan with the objective of modernizing the track structure on selected routes in the quickest possible time may be plaaned even if it involves pre-mature renewal of track.
b. Arrangements taken to execute the works of Short duration & long durations with sketch.
Works of Short duration These are the engineering works which involve the safety of trains and are required to be completed by the sunset. Before commencing any work of this type, the P.W.I should issue a notice to the Station Master in-charge at each end of the block section and obtain their acknowledgment. No engineering work involving the danger to trains should be commenced unless the site has been protected by hand signals, banner flags and detonators. Depending as to whether the train is to be passed through the work site after stopping or at a restricted speed, the line should be protected in the following manner.
Case I : When a train is required to pass at a restricted speed in block section (work to be completed before sunset)
Case II : When the train is required to stop at site of work in block section (work to be
completed before sunset) Works of long Duration These are the planned track works like track renewal works, rebuilding of bridges etc. and the speed restriction is to last for more than a day. Case
III : Protection of line for works of long duration –Train to stop dead Case
IV : Protection of line of works of long duration :( Train to pass at a restricted speed)
b) Pre-temping and Post –temping attentions Pre –temping Operations The following preparatory works should be completed before undertaking the work:-
i. Field Survey:- Field survey should be carried out to determine existing profile of track and to decide the general lift.
ii. Curves:- The beginning and the end of curves/transition curves should be marked on sleepers. Super-elevation and slew should be marked on alternate sleepers to act as guide for the operator.
iii. Ballast :- Ballast should be heaped up in the tamping zone to ensure effective
packing. However, sleeper top should be visible to the operator and the ballast should not obstruct the lifting rollers.
iv. Track drainage and cess: Track drainage should be improved for better retentively of packing. Pumping location should be attended. Low cess should be made-up.
v. Fittings: deficient fittings and fastenings should be made good and all fittings and fastenings like fish bolt, keys, cotter, loose jaws, elastic rail clips, pads etc. should be properly tightened. Worn out fittings should be replaced. Hogged, battered and low joints should be attended.
vi. Sleepers: sleepers should be squared, correctly spaced and gauge corrected. Broken and damaged sleepers should be replaced.
vii. De-stressing of rails: distressing of rails. Adjustment of creep, expansion gaps in joints, buffer rails and SEJs etc, if necessary should be carried out.
viii. Electrified section: In electrified sections, the earthing bond should either be removed or properly adjusted for tamping.
ix. General:
a) Guard rails at the approach of bridges and check rails should be removed temporarily.
b) All obstructions such as rail lubricator, signal rods and cable pipe which are likely to obstruct the tamping tools should be clearly marked and made known to the operator
before the start of work.
c) Wooden blocks and joggled fishplates should be removed temporarily ahead of
tamping.
(d) Post tamping operation The section engineer (P. Way) should pay attention to the following item:- I. Checking and tightening of loose fittings.
II. Replacement of broken fittings.
III. The ballast should be dressed neatly. Proper consolidation of ballast be
between the sleepers should also be done.
IV. Final track parameters should be recorded with the help of recorders
provided on the tamping machine. A copy of this record should be
kept with the section engineer (P-way) and the recorded values should
not exceed the following limits:- Limit of Track parameters after tamping
If the recorder is not available, then track parameters of at least four stretches of 25 sleepers each per kilometer of tamped track should be recorded. In addition the versines and supper-elevation of curves shall be recorded for at least ten stations at a specified chord length.
vi. While working in LWR territory, the provisions of manual of instruction on long welded rails- n1996 should be followed.
vii. The fixtures like check rails removed during pre-temping operation should be restored.
Q. no. 15(i) As a P.Way Engineer how will you use the data of track recording (TRC) to improve the TGI values?
Ans:- The formula for calculation of TGI value is given as under
Where UNI=Unevenness Index TWI=Twist Index GI = Gauge Index ALI=Alignment Index All these indices i.e. UNI, TWI, GI & ALI are calculated from the standard deviations of the track defects measured by the TRC. Thus, TGI is a standard deviation based Track Index and is computed by using the standard deviations of the recorded track parameters viz unevenness, twist, gauge & alignment for each block of 200m length. Higher the values of SD, poorer the condition of track. Thus, the stretches of track needing attention can be identified. Also the specific parameters of track needing attention are identified from the values of standard deviations. Now only the selected portion of track is attended thoroughly to improve the TGI values instead of attention to whole length of track. In addition to SD values the results of TRC provide the records of peak distribution, ABCD categorization of track on short chords, WXYZ categorization on long chords, information of isolated defects with location and magnitude and many other information which help in identification of bad stretches of track needing urgent attention. Thus, the information given by the TRC can be conveniently used for identification of stretches of track needing attention, parameters of track needing attention. Hence, the TGI values can be improved by imparting the planned resources for attention to track parameters at the selected locations instead of attending whole length of track.
Q. 15 (ii) DESCRIBE THE PROCEDURE FOR IN SITU FABRICATION OF GLUED JOINTS.
Ans: - PRE FABRICATION WORKS:-
i. First of all materials and equipments to be used are to be arranged.
ii. The rail to be converted into glued joint and the exact location of the glued joint is selected.
iii. Speed restriction of 30 Kmph should be imposed.
iv. The rail shall be cut with rail cutting machine. The cuts made should be square and right up to the bottom edge of the rail. All burrs should be removed.
v. The holes in the rail should be drilled with 30mm dia H.T.S drill bit concentric to the holes of the fish plates. All the holes should be chamfered and the burrs around holes should be removed.
vi. Proper round holes are cut on the glass cloth carrier and insulating channels, coinciding with the holes of the fish plates to accommodate the bolts, vii. Rolling marks of the rail, occurring in the zone of contact of rail & fish plates shall be ground with a grinder so as to merge with the parent profile/contour. viii. It should be checked that the fish plates should have correct profile so that contact with rail on the fishing surface and web is proper.
FABRICATION WORKS:- 1. In case the fabrication is being done in running track, minimum traffic block of 2 hours shall be taken and track protected with banner flag and detonators. Rail should be made free of fittings over a length of 2.0m on either side.
2. Grinding of rail to a length of 50cm on either end should be done with AG-9 grinder and it shall
be ensured that no rolling mark, rust, dents are in contact with the fish plates.
3. Both the fish plates shall be ground to make the surface free from dust, dents, grease etc.
4. The gap shall be maintained slightly more than 10mm to accommodate the end post. (To achieve this tensor shall be applied).
5. The rail ends shall be aligned laterally and vertically with straight edge using suitable wedges.
6. The rail ends and fish plates surfaces shall be cleaned with acetone and dried completely.
7. The resin and hardener shall be thoroughly mixed to get homogeneous mixture. The mixed glue
shall be consumed within its pot life (Generally 30 minutes).
8. A thick layer of glue shall be applied on mating surfaces of the fish plates simultaneously by two workmen.
9. One piece of clean glass cloth carrier shall be placed on the fish plates and evenly pressedso that the glue squeezes out through the glass cloth. The oozing glue shall be uniformly spread over. A layer of glue shall be applied on inside of the insulating channel followed by then placement on the glued glass cloth carrier on the two fish plates.
10. A layer of glue shall then be applied on the outside of the insulting channel and a clean piece of glass cloth carrier shall be laid.
11. Glue shall be applied to both the faces of end post and placed between the two rail ends.
The tensor may be tightened to place the end post firmly if the same is loose due to more gap.
12. The insulating bushes duly dipped in glue shall be placed in rail holes. The bonding surfaces of rail shall then be coated with a layer of glue and the fish plates made ready shall be placed in position in contact with the rail web.
13. H.T.S. bolts, washers and nuts well cleaned and free from oil, dust etc shall be placed in position and tightened with torque wrench. The torque shall be gradually increased on all bolts. Care shall be taken to tighten inner bolts first and then outer bolts. Finally all the bolts shall be tightened with the torque of 105 kgm.
14. The above operation shall be finished within 45 to 60 minutes, so that minimum 60 minutes setting time is achieved.
15. About 20 minutes after initial tightening, all the bolts shall be re-tightened with the torque of 105 kgm.
16. The joint shall be finished by covering all the visible edges of glass cloth carrier with
glue.
17. After retightening the bolts, the joint is left for setting with tensor in clamped condition.
18. After setting the removed fitting are restored in position, tensor removed and traffic block cancelled.
19. Traffic may be passed at restricted speed of 30kmph for about 2 hours after which the speed restriction shall be relaxed to normal.
Q. no. 15 (iii) DRAW THE SCHEMATIC DIAGRAM OF PQRS DEPOT. Base P.Way Depot for PQRS:-
Q.16. Design an singly reinforced simply supported beam having spam of 5 mm it is carrying a load of 10000 N/m including itself wt.
Assumed
Concrete = M20 grade steel = Tor Allowable bending stress in steel 210 N / mm
Solution :
Let us design the beam using M20 grade of concrete and with for steel having allowable stress in bending as 210N/mm
From IS456 : 1978 allowable compressive stress in concrete for M20 concrete, 7.0 N/mm Modular ration, m = 280 / 3 6bc
= 280 / 3 x 7 = 13.33 = 13.00
Bending moment = wl /8 = 10000 x 5 x 5 = 31250 N - m
8
= 31250000 N-mm
Neutral axis cofficient = N = 1
1 + 6st / m 6bc
N = 1 = 0.302
1 + 210 / 13 x 7
Now let d/b = 2.5 or d = 2.5b
M = kbd Where
K = 1/2 6bc NJ = 1/2 x 7.0 x 0.302 x 0.899 = 0.95
J= 1 - N/3 = 1-0.302 / 3 = 0.899
M = kbd = kb x (2.5b) =
6.25 kb = 6.25 x 0.95 b = 5.9375 b
We have already calculated that the due to load, beam is subjected to bending moment of 31250 000N - mm. Evaluating external moment with the moment of resistance
We get,
5.9375 b = 31250000
or b = 5263157.90
or b = 173.95 mm
say 180 mm
d = 2.5b = 2.5 x 180 = 450 mm
Area of Steel = M/6stJd = 31250000
210 x 0.899 x 450 = 367.84 mm
Let us adopt 12 0 bars
Area of each bar = A / 4 x 12 = 113.10 mm
No. of Bars required = 367.84 = 3.25 113.10
Provide 4 numbers of 12 0 bars.
Provide 30 mm of effective cover design section of the beam will be as given :-
Conclusions : Width of beam = b = 180 mm Depth of beam = d = 480mm Steel Reinforcement = Ast = 4-12 0
Q.No.17 what are the important safety aspects, to be inspected during inspection of manned and unmanned lever crossing?
1) Inadequate visibility: Un manned level crossings are more prone to accidents which can be avoided by maintaining proper visibility. At un manned level crossings where visibility is not clear up to 600 m along the track at a distance of 5 m centre of track, suitable speed restriction should be imposed with the approval of Chief Engineer so as to avoid accidents. All trees, bushes or undergrowth that interfere or tend to interfere with the view from the Railway or roadway when approaching level crossings, should be cut down.
2. Overhauling of level crossing: The level crossings having sleeper other than concrete sleepers overhauled at least once a year or more frequently, as necessary. However level crossings laid on concrete sleepers should be overhauled with each cycle of machine packing or more frequently as warranted by conditions and in no case, should be delayed by more than two years. During overhauling, the condition of sleepers and fastening, rails and fastening should be examined. The wooden sleepers are given a coat of coal tar. In all cases, rail and fastening in contact with road shall be thoroughly cleaned with wire brush and a coat of coal tar applied. Flange way clearance, cross levels, gauge and alignment should be checked and correct as necessary, and the track packed thoroughly before reopening the level crossing for road traffic.
3. Maintenance of check rails: Check rails of level crossings are required to be removed for tamping, over hauling destressing, track renewal and should be re fixed as quickly as possible preferably before leaving site. In case check rails cannot be fixed a speed restriction of 30 km ph will follow, a standing watch man shall be posted to ensure safety besides arrangement for diverting the passage of road traffic. Check rail clearance should be maintained between 51-57 mm. Check rail should be clear and flange way depth should be more than 38 mm.
4) Difference in level between check rail and running rail: At level crossings, at some locations there may be difference of level between check rail and running rail resulting in inconvenience to the road users. Hence, proper attention should be made at the time of overhauling of level crossing by providing proper sleepers underneath the rails.
5. Whistle indicator:-
(i) At the approach to all unmanned 'C' class level crossings or manned level crossing where the view is not clear on either side for a distance of 600 meters and those which have normal position open to road traffic, without interlocking and protection by signals , under special conditions, bilingual whistle boards as per IRPWM annexure 9/5 should be erected at 600 meters along the track from the level crossing to enjoin the Drivers of the approaching trains to give audible warning of the approach of a train to the road users. The Drivers of the approaching train should whistle continuously from the time they pass whistle boards to the time they cross the level crossing. Additional repeater W/L board should also be provided on all unmanned Level crossings. 6 Stop' Boards
(a) On the road approaches to all the unmanned 'C' class level crossings 'Stop' Boards should be provided on the road at either sides of the level crossings at 5 mtr from centre line of nearest track.
(b) This shall consist of a board 675 mm X 525 mm on a suitable post bearing the indication of an engine and the legend "Stop, look out for trains before crossing" in English, Hindi and Regional language. The paint used shall preferably be of luminous variety Generally indicators and warning boards get faded with time when ordinary paint is used. Hence as for as possible luminous paints / luminous strips should be used. As far as luminous strip and luminous paint are concerned, for speed breakers sign boards, whistle boards and stop boards etc. the luminous strip are more effective rather than luminous paint as it is just a like a pre-cast concrete which cannot be deteriorated immediately. .
7) Speed breaker Provision of rumble strips on approaches of level crossings as per the standard design is the responsibility of Road authorities. Matter may be pursued with all State Governments/Road authorities to ensure that rumble Strips are provided on all level crossings as per standard designover the total width of the road i.e edge of the berm to edge of berm with proper road warning signs as per the standard design. However, it is incumbent upon Railways to provide speed breakers as per the standard design on both manned as well as unmanned level crossing irrespective of whether the approach road are metalled are um-metalled, as a temporary safety measure, till such time these are replaced with rumble Strips of proper design by the Road authorities. While providing speed breakers, following guidelines may be observed.
(a) One speed breaker should be provided on either approach of level crossings located within the Railway land boundary at 20m covering full width of the road including berms. For safety reasons, the paint marking should be provided and their maintenance ensured.
(b) Standard warning signs for speed breakers should be invariably provided at a prescribed distanceas follows.
(c)Class of Road Plain Area Hilly area
Class I 120 m 60 m
Class II 60 to 90 m 40 to 50 m
Class III 40 m 30 m
8) Road surface: Road surface is made smooth in such a way that vehicles are not struck to the track. Patch work should be done immediately if required. Hexagonal concrete blocks may be provided, which are durable against wear and tear in gauge conversion and new construction. It has been proved more useful and durable for maintaining the road surface. Secondly it gives better appearance to the road surface and having high resisting power during monsoon season. It should be provided in between the two gates. Outside the gate road surface can be maintained by black top road.
9) Height gauges: - On Electrified sections height gauge should be erected suitably on either side of level crossing so as to ensure that all vehicles can pass with adequate clearance. The height gauge shall be located at a minimum distance of 8 m from the gate post. The road surface up to height gauge is at same level as the road surface inside the gate post.
10) Fencings: Sometimes fencing along the level crossings get damaged, so it become unsafe. If fencing is found broken, it should be immediately attended.
11) Gates and locks are not working properly; there should be arrangement of spare chain in case of emergency.
12) Telephone instrument: Telephone instrument should be always in working order for exchanging the private numbers. If it is out of order it reported immediately for repairing for S&T department.
13) Duty rosters of gateman should be maintained in such a way that gate should always be operated with those gatemen, who are having adequate knowledge of operation of gate as well as protection of train in case of emergency. Those trackman/ gang man/ key man should not be deployed who are not having proper knowledge of safety. However, in case of unavoidable circumstances, it is the duty of PWI in charge to issue competent certificate to those railway staffs who are not working in the capacity of regular gateman. Gate should never be operated under the influence/ pressure of road users. Hence it should always be operated as per railway working rules.
Q.No. 18. Explain periodicity of USFD testing of Rails & welds. Write down various probes being used in USFD testing there function. Action to be taken after defection of defect. Rails After initial testing of rails ,first test free period will be 15%of service life of GMT.
Different type 0f probes:
(a) Single rail tester: Single rail tester is provided with seven probes i.e. 0`, 70` Center Forward )C F), 70` Center Backward (C B), 70` Gauge Face Forward (GF), 70` Gauge Face Backward (NGB). The normal probe (0`) is utilized for the purpose of detecting horizontal defects situated in head, web or foot.
(b) Double Rail tester: The double rail tester is capable of testing both the rails at a time. For each rail, seven probes have been provided for the present i.e. 0`, 70` Center Forward (C F), 70` Center Backward (C B), 70` Gauge face Forward (G F), 70` Gauge Face Backward (G B), 70` Non-gauge face Forward (NGF) and 70` Non-gauge Face Backward (NCB). Other types of probes: 45`, 2MHz probe For testing Gas Pressure, Flashbutt Welded rail joints and half Moon Defect in AT Welds below web foot junction and SEJ. Tandem Scanning (2 Nos. of 45` probes in a rig) for detection of lack of fusion in AT welded rail joints. 70`, 2MHz probe 20 mm circular Flange & Head testing of AT welds (or 20 mm x 20 mm square crystal) 70`, 2MHz Side looking probe (SLP) Half Moon defect in AT welds below web foot junction . Action to be taken after Detection of defects:- Following action shall be taken in respect of defective rails & welds:
Q No. 19: (a) Give in tabular form the latest standard for track structure (Rails, Sleepers with density,
Fastening etc) as prescribed by Railway Board for different type of BG Track.
(b) Explain the criterion laid down for proposing rail renewal.
(a) As per correction slip no 129 & 130 of IRPWM 2004 the desired track structure for BG
route should be as under.
i) PSC sleeper shall be used for all type of renewal.
ii) Minimum clean stone ballast caution below the bottom of sleeper well be 250mm.
(b) The following are to be considered for the criteria for rail renewal.
a. Incidence of rail fractures/failure.:- Where rail fractures occurred in particular section are 5 no. per 10 km stretch per year. Through rail renewal is also allowed in location of track where more than 30 defective welds exists per km.
b. Wear on Rail:- Rail renewal required to be done in following case.
i. Where loss in section reached 6% for 52 Kg. and 5% for 90 R rail.
ii. Where corrosion beyond 1.5mm in the web and foot occurred.
iii. When vertical wear 13mm for 60Kg, 8mm for 52Kg and 5mm 90R rail
occurred.
iv. When lateral wear on curved track on group A & B route 8mm and on C & D route 10mm occurred. On a straight track these limit are 6mm and 8mm respectively.
c. Maintainability of track to prescribed standards:-
ii. Where poor running quality of track in spite of extra maintenance labour engaged.
iii. Condition of rails with regard to hogging/battering, scabbing and wheel burns
becomes bad and not maintainable.
d. Expected service life in terms of GMT carried: - The rail shall be planned for through renewal when total traffic GMT passed beyond 800 for 60 Kg 90 UTS, 525 for 52 90UTS and 350 for 52 kg 72 UTS reached.
e. Plan based renewal:- Renewal to pre determined plan with the objective ofmodernizing the track structure of selected routes in the quickest possible time ma be planned even if it is involves pre mature renewal.
Q No. 20: (a) Indicate various types of mechanical tempers available with the Railways for maintenance of plain track as well as points & crossings also describe pre & post temping attentions to be given to the Track.
(b) Describe the activities to be carried out with BCM working i.e. before screening and after screening.
(a) There are two type of mechanical tempers generally used on the railways as followings:-
i. Off Track Temper
ii. On Track Temper
Off Track Temper:- These are portable tempers and can be taken off the track in a short time.These temper are like tools driven by compressed air, electricity or petrol these tempers work during the interval between trains and do not required any traffic blocks. There are various type of Off Track Temper are available and these are worked in pairs from opposite side of the sleepers diagonally under the rail seat. In order to have maximum consolidation of ballast. The ballast is first loosened around the rail seat in the crib with the help of beaters for a distance of 450mm on either side of the foot of the rail. The temper is then inserted vertically and the temping tools blades are kept about 75 to 100mm away from sleeper so that enough ballast is available between the sleeper and the temping tool blade. The temping period with Off Track Temper is normally about 50 second per sleeper for a lift up to 20mm. One party with two sets consisting of eight persons can temp about 300 sleepers per day.
On Track Temper:- On Track Tempers are self propelled vehicle in which the temping of sleeper is done automatically through the control provided in the operators cabin. There are two type of Track Temper i. e. Light on track temper and heavy on track tempers. Heavy on track temper are superior to the light on track temper and can do automatically and simultaneously lifting, aligning, leveling and temping. Most of the major heavy track tempers/track machines which are in use of Indian Railway are indicated below.
A. Temping Machines for plane track temping are as under:-
i. 08-16 Unomatic
ii. 08-32 Duomatic
iii. 09-32 CSM
iv. 09-3X Temping Express
B. Temping machines for Points & Xing are as under:-
i. 08-275-2S Unimate
ii. 08-275-3S Unimate
iii. 08-275-3S
Pre Temping Attentions:- The following preparatory works should be completed before undertaking the work:-
i. Field survey: should be carried out to determine existing profile of track and to decide the general lift.
ii. Curves : The beginning and the end of curves/transition curves should be marked on sleepers super elevation and slew should be marked on alertnate sleepers for guidance of operator.
iii. Wooden blocks and joggled fish plates provided with defective welds and OHE bonds shall be removed temporarily ahead of temping.
iv. All obstruction such as signal roads, cable pipes etc. which are likely to obstructs temping tools shall be clearly marked.
v. Guard rails at the approach of bridge and check rails at level crossing shall be removed temporarily.
vi. Ballast shall be heaped up especially in temping zone to ensure effective packing, Sleeper top shall be kept free from the ballast.
vii. Blowing/Pumping joints shall be attended and round ballast replaced with clean and angular ballast.
viii. Sleeper shall be squared, correctly spaced and gauged properly.
ix. Fitting and fastenings deficient shall be restored, loose tightened and wornout replaced.
x. Hogged, battered and low joints shall be attended.
Post tamping attentions:-
Section P.Way Engineer attached with machine shall ensure about the following items:-
i. Checking and tightening of loose fittings
ii. Replacement of broken fittings
iii. Dressing up of the ballast and proper consolidation of ballast in crib/shoulder.
iv. Final track parameters shall be recorded in the register.
v. The fixtures like check rail, guard rail, wooden block, joggled fish plates bonds etc.
removed/adjusted from the track shall be restored.
(b)
1. Activities to be carried out with BCM working before screening are as under:-
i. Foot by Foot survey of the section should be done to see the condition of ballast, track components, cess width and availability of land for waste disposal.
ii. Longitudinal profile and alignment should be final. Depth of cutting and magnitude of lifting of track should be decided on the bases of proposed rail level.
iii. Putting extra ballast into screening zone of BCM to ensure that the maximum possible ballast is screened by the BCM
iv. Renewal of worn out and broken fittings.
v. All type of obstructions should be removed in advance .
vi. L-Xing should be opened in advanced so as to enable machine to work.
vii. Sleeper should have all the fitting intect so that no sleeper become loose and come in the way of cutter chain.
viii. Gas cutting equipment should be available at site to cut of any obstruction like rail pieces, pipe etc. which might get in tangled with cutting chain.
ix. A trench of 30 cm depth and 1mtr wide should be made for lowering cutter bar by removing one sleeper.
2. Operations required after BCM working
i. At the end of work, about five sleeper spaces are left without ballast. These should be filled manually with the clean ballast.
ii. The vertical and lateral clearances for OHE signal post and any other structure should be checked and adjusted before clearing the BCM block.
iii. Ballast recoupment activity should synchronies with deep screening activity so as to enable raising to normal after necessary packing.
iv. One watchman should be posted at the location where cutter bar and chain are left whenever considered necessary.
v. It is desirable that one round of tamping along with DTS should be carried out immediately after deep screening to resume traffic at a speed of 40 Kmph.
vi. Cleaning of cess, screening of left over ballast and making standard of ballast profile.
vii. Removal of the muck and disposed the same away from the track.
Q. No. (21)(a) Describe have relaying work by PQRS or TRT M/c including pre & post relaying activities.
(10) Ans:- Portal Cranes (PQRS) Para 3.5. 1. General
i) Portal Cranes, commonly referred to as PQRS, are used for mechanized tack renewals. These are loaded on BFRs' and hauled to the site. Normally two portal cranes are deployed for the relaying work at site, while the third one is utilised for pre-assembly of new track panels at the base depot. The third portal crane also acts as a standby in case of breakdown of the portals at site.
ii) Tamping machine should be deployed behind the portal cranes for lifting and tamping of newly laid track.
iii) Minimum block of 2 hours and 30 minutes duration should be arranged.
iv) Adequate spares for working of all the machines ( Portal Cranes and Tampers etc ) should be arranged in advance and regular supply should be ensured The base depot is required to cater to the following activities:
a) Unloading of PSC sleepers from the rake and staking.
b) Fabrication of new panels.
c) Unloading of released panels.
d) Dismantling of released panels.
e) Loading of pre-fabricated new panels.
f) Formation of PQRS rake.
g) Maintenance of machines.
h) Dispatch of released materials.
i) Loading/unloading of ballast, if the base depot is also to be used as ballast depot.
a) Unloading of PRC sleepers from the rake and stacking.
b) Fabrication of new panels.
c) Unloading of released panels from PQRS rake.
d) Dismantling of released panels. ii) It is desirable to locate the Base Depot at a central place such that the distance of remotest work site on either side does not exceed 60-70 kms. At the same time, the site
selected should be accessible by road; there should be electric power supply and watering facilities. The base depot may have facility of entry and exit on both sides from the running line
iii) For smooth working, the base depot should have at least three sidings of 500 metres each connected to a shunting neck of 350 meters. Of these, at least two sidings should be provided with auxiliary track for movement of portal cranes.
iv) It is desirable to illuminate the base depot so that the activities listed in item
(i) above can be undertaken safely at night.
v) To strengthen depot working, it is desirable to install a few hand operated/motorised gantry cranes moving on auxiliary tracks in addition to the third portal crane in the depot. Some of these gantry cranes can be of 6.5 metres height from rail level to facilitate repair to portal cranes. Pre-Relaying Operations Following operations should be ensured before actual relaying:-
i) The requisite survey shall be carried out and the longitudinal profile and alignment shall be finalised as per relevant provisions in the Indian Railways Permanent Way Manual- and schedule of dimensions
ii) Track may be deep screened one or two days in advance of relaying. The ballast section should be built up to the bottom of sleepers to facilitate relaying. The balance quantity of screened ballast should be trained out after relaying.
iii) Auxiliary track should be laid at 3400 mm gauge keepingthe central line same as that of main line track, as shown in Sketch 3.4, CST-9 plates or wooden blocks ofsize 560 × 250 × 125 mm should be used at 1.5 to 2.0 metres distance for laying the auxiliary track. The length of auxiliary track should match with the daily progress of work.
iv) The level of auxiliary track should be same as that of existing main line track and must have proper longitudinal and cross levels to avoid derailment of portal cranes. In no case, the auxiliary tack should be more than 50mm higher than the existing track.
v) Removal of ballast from the crib and shoulders up to the bottom level of the sleepers should be ensured.
vi) Fullfittings of the old sleepers should be ensured to avoid their falling off while liftingreleased panels.
vii)Sleepers must be in single piece. All Broken sleepers should be removed or replaced in advance.
viii) On girder bridges, the guard rails at the approaches on both ends should be removed temporally.
ix) In case a level crossing is to be encountered, it should be opened in advance.
x) Proper planning and insertion of Switch Expansion Joints at correct locations should be ensured.
xi) Cutting of LWR/SWR to single rails should be ensured for liftingreleased panels. Otherwise, replace the existing running rail by service rails for the stretches which are to be relaid during the next day.
xii) Temporally disconnect or remove any other permanent obstructions such as cables, signalling rods and any other installations like embedded rail pieces, tie bars etc. to allow unhindered progress of work.
xiii) Availability of under noted equipments should be ensured at site:-
a) One set each of rail cutting and gas cuttingequipment in good working condition.
b) Two sets of rail closures of the each rail section being laid, in various sizes from 0.5m to 3m lengths. c) 4 sets of junction fish plateswith bolts. xiv) Portable walkie-talkie sets should be provided at each relaying site for effective communication between the site of work and the adjoining stations.
xv) Extra number of track panels should be fabricated in the base depot to maintain a buffer stock for one or two days of relaying work so that work at site does not suffer for want of depot working. Post Relaying Operations Following post relaying operations should be ensured :-
i. Clearance of track from any obstructions before removal of traffic block.
ii. ii) Complete track lifting including their correct positioning & tightness.
iii. iii) Proper lifting, packing, ballast regulating and compaction/stabilization of track to
raise the speed of the different stretches as per the table II of para 308 of IRPWM
iv. . iv) Training out of adequate quantity of ballast over the newly relayed track to full ballast section. Ballast recoupment activity should be properly synchronized with the relaying activity so as to enable raising of speed to normal in three cycles of tamping by on-track tampers.
v. v) Picking up of left over released materials.
vi. vi) Dismantling of auxiliary track and relaying the same in advance for the next day's work.
vii. vii) Restoration of cables and other fixtures e.g. guard rails on level crossing which were removed temporarily.
viii. viii) Tie tamping machines, BRM and Dynamic Track Stabilizer should be deployed to enable raising of speed to normal. ix) Provision of SEJ as per approved plan. In-situ welding of panels and destressing of LWR should be done after welding of panels. Track Relaying Train (TRT) Operations Prior to Development of Machine
i. Base Depot a) Ensure proper selection of Base Depot site. The base depot for TRT should be centrally located (30-40 kms. lead) in the area of working. It should have water, electricity and communication set up. Also, accommodation for machine and P. way staff should be available.
b) Provide sufficient stock of new sleepers, elastic rail clips fastenings, liners and rail pads in the base depot.
c) Ensure proper line and level of auxiliary track for 3400/3700 mm gauge portal working.
d) 30 nos. BFR's should be modified for one set of TRT. 160 sleepers are loaded in one BFR and about 1500-2000 sleepers should be loaded as required during block. While loading PSC sleepers on special BFRs, wooden battens of 75 mm × 75 mm should be provided between different layers on the outer side of MCI inserts. This will enable gripper to function properly.
e) Load rail fastening like elastic rail clips, liners and rail pads as required during block. Condition ofsleepers should be seen .All corroded and broken steel/CST-9 sleepers should be marked.
ii. iii) Foot by foot survey should be carried out to identify the locations having lateral or longitudinal infringements. There should be no infringement within one metre of sleeper ends.
ii. iv) Adequate ballast should be available before relaying operations start sothat tamping and raising of speed is not delayed.
ii. v) Deep screening should be carried out in advance wherever feasible. Excess ballast should be removed and shoulders should be brought down wherever feasible to sleeper level. It should be ensured that the ballast bed is fully consolidated.
ii. vi) Check-rails of the level crossings falling in the range of work should be removed in advance.
ii. vii) All longer fish bolts and joggled fish-plates should be removed from the range of work.
ii. viii) New rails should be unloaded, paired, fishplated or welded in one piece (as required for a day's work) and set at about 1.5 metres from track centre. Rails should be kept on foot with
adequate support so that they do not get shifted during working of the TRT.
ii. ix) All obstructions like creep posts, alignment posts etc. within 1 metre ofsleeper end should be removed.
ii. x) All reverse jaw sleepers in case of CST-9 sleeper track should be removed. Alternatively, their lip may be cut by lip cutter sothat railremoval is not obstructed.
ii. xi) All longer wooden sleepers from joints be either removed or cut to size in advance of
TRT working.
ii. xii) Interlaced sleepers of height different from remaining sleepers should be removed.
ii. xiii) Ensure that the fittings in old track are not jammed and can be removed while working. Loosen them if any problem is anticipated.
ii. xiv) In case o f CST-9 sleepers, gauging should be done in advance to avoid hittingof sleepers by sled assembly during lifting of CST-9 sleepers.
ii. xv) Seven wooden sleepers should be laid in track at location 5 sleepers behind the rail cut and ballast around them removed for easy placement of plow.
ii. xvi) The location of cut at new site of work should be so planned that it matches with the new rail end for threading at the start of work.
ii. xvii) At location where relaying is to start, two rail pieces of 7.3 metres length are cut and connected together using well greased fishbolts to enable quick opening during block.
ii. xviii) Plan the location of cut in the old track at the closing of work site so that it matches with the rail end of new rail panel. Some extra gap is preferable, as the new rail while threadingin is likely to straighten and extend.
ii. xix) Walkie-talkie sets for communication should be available with engine driver, Junior/Section Engineer (P. way) machine staff and adjoining stations.
ii. xx) Ensure availability of S & T staffto connect- any wire/rodding disturbed during the block, and OHE staff (in electrified section) for opening of temporary bonds and bondingback after the work. ii. xxi) Ensure removal of OHE bonds before the block. Temporary bonding of the OHE masts should be done by OHE staff while removingthese bonds .
ii. xxii) Ensure earth bonding of new rail panels. There should be minimum 3 bonds in each panel length of 300 metres.
ii. xxiii) Ensure removal of alternate keys in case of CST-9 sleepers and inside alternate keys in case of ST sleepers. The remaining keys should be checked for easy removal.
ii. xxiv) Existing small nos. of PSC sleepers (2 rail lengths) should be replaced with wooden
sleepers to avoid loss of time while working. High temperature destressing of the old tack should be carried out as provided
(b) For a1o curve on BG 110 Kmph line with 80mm cant & 100 meter transition length find out.
(i) Safe & equilibrium speed and rate of change of cant and cant deficiency at 110 KMPH. (5
Q. No. (22) (a) What are the classifications of high speed routes and what are the standards
for each route category of the following –
(i) Rails
(ii) sleepers
(iii) Fastenings
(iv) Ballast cushion.
b) Pre & post attentions for working of unimate M/c and what is JPO for Points & xings packing by Unimate M/c. (15)
Para 3.2 Tamping Machine For Points & Crossing (Unimate) Tamping of turnouts shall be planned to cover sufficient length of approach track taking into account the special track features on either side. In case of the turnout leading to loop line, the turn in-curve shall also be tamped. In addition to provisions contained for plain track tamper, the following aspects shall be taken care of. '
Para 3.2.1 Pre Tamping Operations
i. Layout including spacing of sleepers as per relevant drawings shall be ensured.
ii. The nose of the crossing may get battered or worn or the sleepers below it may get warped or bent. In such cases, the crossing should be reconditioned or replaced and sleepers below the crossing should be attended.
iii. High points on the turn out and approaches should be determined and general lift should
be decided. General lift of minimum 10 mm must be given.
Para3.2.2 Operations during Tamping:
i. For packing turnout, main line is to be tamped first. While tamping mainline, the additional lifting arrangement lifts the turnout side rail also. The lifted end of sleepers should be adequately supported on wooden wedges till it is packed/tamped
ii. The machine carries out correction of alignment and levels on main line portion. On the turnout side, only tamping without lifting and lining shall be done.
iii. The squeezing pressure to be applied is as follows:
a) ST sleepers/wooden sleepers: 110- 115/sq.cm
b) PSC sleepers: 135-140 kg/ sq. cm
iv. In case there is hindrance to achieve adequate penetration of tool, penetration assistance system should be used to facilitate insertion of tools in ballast and to accelerate lowering of tamping units.
v. During and before tamping, S&T and Electrical staff should also be associated to complete their portion of work 3.2.3 Post Tamping Operations The post tamping operations shall be same as that of plain track tamping. Special care should be taken to tighten and complete the fittings. All S&T/Electrical connections removed before tamping shall be restored back. JPO for points & Crossing packing by Unimate:-
Pre-Traffic Block activities
i. Oiling & greasing of P.Way connections.
ii. Oiling & greasing of S&T connections.
iii. Oiling & greasing of S&T gears of point machine.
iv. Application for disconnection by S&T Deptt.
v. Application for Traffic Block by Engg. Deptt.
During-Traffic Block
i. Machine movement for site & setting up of machine.
ii. Removal of S&T gears during the disconnection of point.
iii. Start of Tamping Work.
iv. Tamping of switch portion should generally by taken up first so that while tamping work is in progress, S&T reconnection work can go ahead.
v. Reconnection of S&T gears after tamping of switch portion.
vi. Completion of tamping, S&T reconnections & remaining work.
vii. Clearance of traffic block.
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