Indian Railway Schedule of Dimensions (BG) PDF

SCHEDULE – I STANDARD DIMENSIONS 1676mm GAUGE (BG) CHAPTER I – GENERAL The DIMENSIONS given in this Schedule-I have been classified under two heads nam...

SCHEDULE – I STANDARD DIMENSIONS 1676mm GAUGE (BG) CHAPTER I – GENERAL The DIMENSIONS given in this Schedule-I have been classified under two heads namely for ‘Existing works’ and for ‘New works’. Existing works means the works which were existing before issue of Indian Railway Schedule of Dimensions (BG), Revised-2004. New works would include altogether new constructions, additions of new lines, new structures, gauge conversion and doubling. However, it does not include the works of alteration such as shifting of a Points and Crossings, extension of siding, extension of loop line, alteration in building etc. The dimensions, except for existing works, are to be observed on all 1676 mm gauge on Indian Railways for execution of new works. Provided that infringement to any provision of IRSOD Chapter I, II, III, V, VA & VB of Schedule I can be condoned by the Commissioner, provided further that for infringement beyond the dimensions prescribed in Schedule II, if any, or wherever specific mentions appear in Schedule I, sanction for condonation shall be obtained from Railway Board through Commissioner/Chief Commissioner of Railway Safety. [See Diagram Nos. 1A, 1A (Modified), 1B, 1C and 1D] NOTE: (1) Items 8 and 10 are applicable only to structures outside station yards. All other items are of general applicability. (2) For running EMU and other 3660mm Stock on existing works, clearances prescribed in items 13(i) (a) and (ii) of Chapter I “Tunnels, Through and Semi Through, Girder Bridges" shall also be required for all structures governed by items 1(i), 7(i), 8(i) and 12 of this chapter and not only for tunnels, through and semi through girder bridges. Spacing of Tracks:- 1 Minimum distance center to center of straight tracks (i) For existing works 4265mm (ii) For new works/addition to existing works 5300mm Note: (a) See Appendix for extra clearance required on curves. (b) For spacing of tracks in tunnels, Road Over Bridges/Flyovers, through and semi through girder bridges, see item 13. 1  (c) New/Additional works cover laying of new line and new running loops. Extension of existing line or replacement of points & crossings will not be treated as new work. (d) OHE mast and Signal post shall not preferably be provided in between tracks. However, under unavoidable circumstances, the clearances mentioned in para 1(ii) above shall be increased by equal to the width of such provisions/structures/foundation, as the case may be. (e) In case of tunnels, ROBs, flyovers, through & semi-through girder bridges, where center to center distance lesser than 5300mm between tracks has been provided, lesser center to center distance between tracks can be provided on approaches also up to adequate distance to facilitate gradual increase in center to center distance up to minimum 5300mm. (f) Further, in case lesser than 5300mm center to center distance between tracks has been provided in the existing station yard, lesser center to center distance between tracks can be provided on approaches towards block section also, up to adequate distance to facilitate gradual increase in centre to centre distance up to minimum 5300mm. Curves:- 2 Minimum radius of curves 175m (10 degrees) Bridges:- 3 Bridges must conform to the requirements of chapter IV of the Railways opening for the Public carriage of Passengers, Rule 2000. On existing bridges where there is nothing solid between sleepers to prevent a derailed wheel dropping, the clear distance between two consecutive sleepers shall not exceed 510mm. The clear distance between the joint sleepers shall not, however, exceed 200mm and that between the two consecutive sleepers 450mm in all new constructions and in existing bridges when regirdering or carrying out through sleeper renewal. Bridge sleepers resting directly on longitudinal girders should not be less than 150mm deep exclusive of any notching which may be required to allow for cover plates, camber, etc and not less than 305mm greater in length than the distance outside to outside of girder flanges subject to a minimum of 2440mm. The minimum length of steel trough sleepers should be the distance outside to outside of girder flanges subject to a minimum of 2440mm Rails:- 4 Minimum clearance of check rails for a curve 44mm Note: (a) This clearance must be increased by not less than half the amount of any difference between 1676mm and the gauge to which the curve is actually laid. (b) Check rail to be provided in curves where the radius is 218 m or less i.e. curvature is 80 or more. It may be required in the case of flatter curves also, if high speed is contemplated. 5 (i) Minimum clearance of check rail at a level crossing 51mm (ii) Maximum clearance of check rail at a level crossing 57mm 2  (c) The clearances as mentioned in item no. 8 (iii) (a) and (b) above will not be applicable in case of bridges, tunnels & ballastless track (including washable apron). 9 Minimum horizontal distance of any telegraph post measured from the centre of and at right angles to the nearest track. (i) For existing works The height of the post plus 2135mm (ii) For new works or alterations to existing works The height of the post plus 2360mm Note: When the line is in cutting a telegraph post erected outside the cutting, must be at a distance from the edge of the cutting not less than the total height of the post. 10 Height of Road Over Bridges & Foot Over Bridges: (a) Minimum height above rail level for a distance of 915mm on either side of the centre of track for overhead structures 4875mm (b) Where D.C. electric traction is in use or is likely to be used, this dimension shall be 5410mm (c) Where 25 KV A.C. traction is likely to be used, the minimum height above rail level for a distance of 1600mm on either side of the center of track shall be as under : (i) Light Overhead structure, such as Foot Over Bridges 6250mm (ii) Heavy Overhead Structure, such as Road Over Bridges and 5870mm Flyovers Note: (a) See appendix for ‘extra clearance required on curves'. (b) In case of restricted height of existing structures, a special study shall be made, as indicated in Appendix-A to Chapter V-A before 25 kV A.C. traction is introduced. Accordingly, only in such cases, the minimum height above rail level shall not be lower than 5070mm in case of Heavy Overhead Structure (such as Road Over & Flyover) and 5270mm in case of Light Overhead Structures (such as Foot Over Bridge) for a minimum contact wire height of 4800mm from above rail level. OHE arrangements shall be as per RDSO Drawings. (c) In areas where 25 kV A.C. traction is used or likely to be used, if any turnout or crossover is located under a heavy overhead structure or within 40m from its nearest face, irrespective of the position of level crossing gate, the minimum height of such overhead structure shall be 6250mm*. In case the turnout is beyond 40m; but the level crossing gate is within 520m from the nearest face of the bridge, the height of such overhead structure shall be 6250mm*. (d) The height mentioned against items 10(a), 10(b) & 10(c) above shall be measured from the higher or super elevated rail. (e) On lines, existing or proposed to be electrified on 25kV A.C. system, necessary provision shall be made in overhead structure and overhead equipment, if necessary, by using longer traction overhead equipment masts to 4  permit an extra allowance of 275mm for raising of track in future to cater for modern track structure in the form of increased ballast cushion, larger sleeper thickness and deeper rail sections. * In case of restricted height of existing heavy overhead structure, minimum height above rail level shall not be lower than 5270mm, adhering to the provisions of note (b) above. (f) For Mumbai Suburban, the height of Foot Over Bridges mentioned under para 10(c)(i) above may be reduced to 5750mm subject to following conditions: (i) The minimum height of the contact wire shall be 4800 mm. (ii) A special study shall be conducted as indicated in appendix A of chapter V-A to ascertain the feasibility of the contact wire height as 4800mm. (iii) There shall be no crossover below FOB or within 40 m from the face of FOB. (iv) There shall be no level crossing within 520 m from face of FOB. (v) The maximum height of rolling stock shall be restricted to 4420 mm. (vi) The height shall be measured from the higher or super-elevated rail. 11. Clearance for Power line crossings including Telephone line crossings of Railway Tracks – 11(i) Clearances for Power line crossings in Non-Electrified & Electrified Territory: SL Over head crossing voltage Minimum clearances from Rail Level Minimum Existing power New power line clearance between line crossing for crossing or crossing highest Traction Non-Electrified planned for alteration Conductor and Territory lowest Transmission line crossing conductor (1) (2) (3) (4) (5) 1. Upto and including 11kV Normally by underground cable 2. Above 11kV & upto 33kV 10860 mm 14660 mm 2440 mm 3. Above 33kV & upto 66kV 11160 mm 14960 mm 2440 mm 4. Above 66kV & upto 132kV 11760 mm 15560 mm 3050 mm 5. Above 132kV & upto 220kV 12660 mm 16460 mm 4580 mm 6. Above 220kV & upto 400kV 14460 mm 18260 mm 5490 mm 7. Above 400kV & upto 500kV 15360 mm 19160 mm 7940 mm 8. Above 500kV & upto800kV 18060 mm 21860 mm 7940 mm Note : (i) All height/clearances are in mm and under maximum sag conditions. (ii) If the crossing is provided with a guarding, a minimum clearance of 2000mm shall be maintained between bottom of guard wire and highest traction conductor. (iii) Power line crossing in yards and stations area shall be avoided. 5  (iv) For electrification works of existing track or construction of new track/gauge conversion with electrification, existing power line crossings can continue, if dimensions are as per column (5) above, even if dimensions of column (3) are not satisfied i.e., for electrification works column (3) is not applicable. 11(ii) Minimum clearance between any conductor not adequately insulated and any railway structure under most adverse conditions. SL Voltage Minimum Clearance (1) (2) (3) (a) Upto and including 650 volts 2500mm (b) Above 650 volts and upto & including 33 kV 3700mm (c) Above 33 kV and upto & including 66 kV 4000mm (d) Above 66 kV and upto & including 132 kV 4600mm (e) Above 132 kV and upto & including 165 kV 4900mm (f) Above 165 kV and upto & including 220 kV 5500mm (g) Above 220 kV and upto & including 400 kV 7300mm (h) Above 400 kV and upto & including 500 kV 8200mm (i) Above 500 kV and upto & including 800 kV 10900mm 11(iii) Minimum height above rail level for telegraph, telephone 6100mm and other such low tension wires crossing a railway 11(iv) Minimum Horizontal Distance of Structures: The minimum horizontal distance measured at right- angle to, and from the centre of nearest track to any part of the structure above ground level, carrying electrical conductor crossing a railway line shall be: (i) For new structure : (H+6) m (ii) For existing rigid well founded post/structures : 3m, or 1.5m away from the toe of embankment/top of cutting, whichever is more Where, ‘H’ is the height of post/structure from nearest ground level Note : 1. Rigid well founded post/structure: Any post/structure which is so constructed or guyed as to remain in a vertical position, or failing this to continue to provide the minimum horizontal clearances of 2.135m from the centre of nearest track, with one or all of the conductors broken or with its conductors attached, when subjected to maximum wind pressure, shall be considered to be a “rigid well founded post/structure”. The existing rigid well founded post/structures, presently at a distance equal to or more than (ii) as given above, but less than (H+2.135)m, shall be inspected by railway’s nominated electrical official once in a year jointly with the owner of the post/structure and certify the safety of the structure, keeping appropriate records of inspections. 6  2. If the existing post/structure carrying electrical conductors crossing a railway line, is not rigid and well founded then the minimum horizontal distance, measured at right angles from the centre of nearest track, shall be equal to height of post/structure above ground level plus 2.135m. Interlocking and signal gear:- 12 Maximum height above rail level of any part of interlocking or signal gear 64mm for a width of 1600mm or 1830mm in the case of tunnels, through and semi- through girder bridges on either side of centre of track subject to the restriction embodied in the note (a) below. Note: - a) For a distance of 229 mm outside and 140mm inside the gauge faces of the rail, no gear or track fittings must project above rail level except such parts as are required to be actuated by the wheels or wing rails and point rails of special crossings leading to snag dead ends or elevated check rails of crossing or check rails/check flats of diamond crossings. b) Signal wires or supports for signal wires may be allowed at not less than 1600 mm or 1830mm in the case of tunnels or through or semi-through girder bridges [see note at item 32 of chapter IV(A)] on either side of the centre of track provided that they are not more than 203mm above rail level. c) Metal covers with ramps on both sides must be provided over all interlocking gear projecting above rail level between the rails of a track to prevent hanging couplings from damaging the gear. Tunnels, Through Girder Bridges and Semi-Through Girder Bridges: [(See diagram No.1A; 1-A (Modified)] 13 (i) Minimum distance at centre to centre of track (a) For existing lines 4495mm (b) For new works and alterations to existing works 4725mm (ii) Minimum horizontal distance from centre of track to any structure shall be as follows: Height above rail level Horizontal distance from centre of track (a) From 0.0mm to 305mm 1905mm (b) From 305mm to 1065mm 1905mm increasing to 2360mm (c) From 1065mm to 3355mm 2360mm (d) From 3355mm to 4420mm 2360mm decreasing to 2135mm (e) From 4420mm to 5870mm 2135mm decreasing to 915mm Note: (i) Where electric traction is not likely to be used, over-head bracing of bridges may be 5030mm above rail level for a distance of 1370mm on either side of the centre of track. (ii) In case of existing structures, a special clearance study shall be made which will be accepted by Electrical Inspector of the Railways, as indicated in Appendix-A to chapter V-A before electric traction is introduced. (iii) See Appendix for extra clearances required on curves. 7  (iv) Where D.C. traction is in use, Para 13(ii) (e) above shall be as under: From 4420mm to 5410mm : 2135mm decreasing to 915mm (v) Tunnels, through girder and semi through girder bridges outside station yards should be treated as heavy overhead structures such as ROB for electrification works and the same dimensions as mentioned in note (c) at para 10 above shall be applicable and OHE arrangement shall be as per RDSO Drawings. Safety Refuges: 14 Maximum distance apart of refuges in tunnels 100m 15 Maximum distance apart of trolley refuges: (i) On bridges with main spans of less than 100m 100m (ii) On bridges with main spans of 100m or more A refuge over each pier Formation width: 16 Formation width for single line straight track (i) For existing works (a) Minimum width in embankment 6850mm (b) Minimum width in cutting (excluding side drains) 6250mm (ii) For new works/alteration to existing works (a) Minimum width in embankment 7850mm (b) Minimum width in cutting (excluding side drains) 7850mm 17 Formation width for double line straight track (i) For existing works (a) Minimum width in embankment 12150mm (b) Minimum width in cutting (excluding side drains) 11550mm (ii) For new works/alteration to existing works (a) Minimum width in embankment 13160mm (b) Minimum width in cutting (excluding side drains) 13160mm Note: (a) The minimum formation width is based on: (i) Ballast section having 1.5:1 side slope. (ii) Cross slope on top of formation of 1 in 30 (iii) Track center in case of double line section is 5300 mm 8 18 Formation width on curves: (a) Increase due to extra ballast on outside of curves: On curves, the actual width to be provided should take into account 150mm extra widening of ballast shoulder (500mm in place of 350mm) required on the outer side of curves. Thus, additions in the width on this account will be 150mm for single line and 300mm for double line. (b) Increase on double line due to effect of super-elevation: Due to requirement of extra clearances on double line on curves, increase in track centre with corresponding increase in formation width would be necessary to take into account the effect of super- elevation. Increase in formation width on curves will be decided after taking into account the increase mentioned in (a) & (b) above. 19. Gauge on straight and curves: The gauge shall be as follows: (i) Straight including curves of 350m radius or more -5mm to +3mm i.e. 1671mm to 1679mm (ii) For curves of radius less than 350m up to +10mm i.e.1686mm 9