COMPLETE SPECIFICATION OF ‘BALLASTLESS TRACK WITH INDIGENOUS FASTENING SYSTEM (BLT-IFS)
The following specification particularly describes the invention and the manner in which it is to be performed.
Detailed description of the invention:

1. General Arrangement:
Concept of combination of beams & slab using in-house RCC design skills has been used for BLT-IFS where rail is supported on equally distant beams and loads are transferred to subgrade through slab monolithically casted at site along with beams. The beam spacing of 600 mm to control rail deflection and fitness for full speed and 25 t axle load has been provided. Partly casted canted rail seat beam (PCRSB) in rail seat portion to be casted in concrete sleeper plant with M-55 grade concrete to ensure required quality in rail seat area. The arrangement of RCC beam is shown in drawing no. RDSO/T-8304. These partly casted rail seat beams (PCRSB) are joined with RCC base slab by reinforcement and in-situ second pour concreting after track is assembled to required line and level and supported with the help of jigs and fixtures to act as monolithic structure. The new design has been named as ‘Ballastless Track with Indigenous Fastening System (BLT- IFS)’. The general arrangement of BLT-IFS is shown in drawing no. RDSO/T-8305.

In the general arrangement, BLT-IFS, top surface of RCC the slab has one directional cross-slope of 1 in 100 towards drain side (away from platform wall, in case of washable apron) to facilitate drainage. Depth of beams (PCRSB) in central potion & slab is kept same to have shuttering less construction. PCRSB is casted in concrete sleeper plant with raised rail seat area, which projects out of final level concrete top of the BLT/Washable apron in order to facilitate non-submergence of rail seat and cleaning. RCC slab is of M40 grade of concrete which is supported over M20 grade plain concrete base and lean concrete over compacted ground.

2. Various Components of BLT-IFS Assembly:

A) Canted Partly Casted Rail Seat Beam (PCRSB): This beam has been designed to accommodate rail seat assembly for BLT-IFS as per drg. No. RDSO/T-8304. These beams are to be manufactured in concrete sleeper plants with M-55 grade concrete as per RDSO drawing no. RDSO/T-8304. PCRSB is casted along with main reinforcement bars and shear reinforcement ties/rings. A mark line is engraved in PSCRSB indicating top level of RCC slab to facilitate in-situ concreting at site. All surfaces of PCRSB below this mark line are made rough to facilitate proper joining of PCPSBs and RCC base slab. SGCI inserts to drawing no.RDSO/T-6901 & conforming to RDSO Specification No.IRS-T:46/1996 have been used in canted PCRSB.

Acceptance criteria for canted PCRSBs will be dimensional conformity as per the drawing, testing of concrete cubes after steam curing & 14 days water curing for M55 grade of concrete, as required by ‘Specification of PSC sleeper’, IRS-T:39, August 2011 of RDSO. Inserts on the canted PCRSB would also be tested for pull out strength which should be a minimum of 6 ton.

This component i.e. ‘canted PCRSB’ has been developed especially for BLT-IFS assembly and hence is a part of claims made in this application.

B) SGCI (spheroidal graphite cast iron) Bearing Plate (SGBP):

The SGCI bearing plate drawing no. RDSO/T-8307 has been designed to hold the rail and accommodate elastic rail clip shoulders casted on the bearing plate. This casted bearing plate shall be held on canted PCRSB with (Elastic Rail Clip/Mk-V) through the inserts to drg. No. RDSO/T-6901 casted in the canted PCRSB.

The SGBP material used is same as that of SGCI inserts i.e. complying to IRS T-46 of RDSO. Bearing Plate shall be casted with SGCI conforming to the requirements of Grade SG 500/7 of IS: 1865-1991 “Iron Castings with spheroidal or nodular graphite – specification” (Third Revision)..

SGBP shall be tested for metallurgical & chemical properties including phosphorous content, ultimate tensile strength & elongation on Standard Test Bar (STB) & Proportionate Test Bar (PTB), BHN hardness as per IRS T-46 issued by RDSO & dimensions as per drawing RDSO/T-8307.

The SGCI bearing plate (SGBP) has been developed especially for BLT-IFS assembly and hence is a part of claims made in this application.

C) Beam/Base Pad: Between SGBP and canted PCRSB at rail seat location, 10mm thick Composite GRSP (drg no. RDSO/T-8299) for BLT-IFS shall be used as per RDSO Specification RDSO/M&C/RP-200/2007.The beam/base pad has been developed especially for BLT-IFS assembly and hence is a part of claims made in this application.

D) Transition System: Transition system (RT-8301)of track on either end of BLT-IFS section have been prepared to provide smooth transition from lower to higher track modulus or vice versa so that rough riding is avoided at entry and exit point of BLT-IFS and to avoid damage to BLT-IFS structure at ends. Transitions arrangement for BLT-IFS in tunnel and via-ducts has also been developed as per drawing no. RDSO/T-8418 with use of softer pad (Drg No.RDSO/T-8419 ) and softer base pad (Drg.No.RDSO/T-8420). The transition systems to drawing no.RDSO/T-8301 and RDSO/T-8418 along with softer pad (Drg.No.RDSO/T-8419) and softer base pad (Drg.No.RDSO/T-8420) have been especially developed for use in BLT-IFS and hence is a part of claims made in this application.

E) 60kg(UIC) Rail, SGCI (drawing no. RDSO/T - 6901) 6mm thick (drawing no. RDSO/T -3711), GFN-66 insulating GFN liners (drawing no. RDSO/T -3706 & ERC Mk-III (drawing no. RDSO/T- 3701) have been used within assembly. These are standard items & as known art of Indian Railway. Hence, these items do not form part of claim of their application. ERC-Mk-V (RDSO/T-5919) is already a patented item of RDSO. However, they are part of the assembly of BLT-IFS.

F) Jigs & fixtures: For holding and making fine adjustment of rails / track in vertical & horizontal directions during the in-situ casting, Jigs & fixtures have been used as per typical arrangement drawing no. EDO/T-2263. Such jigs and fixtures can be fabricated through Railway workshops or trade through working agencies having undertaken construction of ballastless track in past. This is an arrangement to facilitate construction and a common arrangement. This is not part of patent application. However, they are part of the assembly of BLT-IFS.

G) Reinforcement Steel: Reinforcement bars either of Fe 415/Fe 500 grade conforming to IS:1786–2008(High yield strength TMT deformed bars) have been used in canted PCRSB & RCC slab. The reinforcement steel is a commonly available item. This is not part of patent application. However, they are part of the assembly of BLT-IFS.

Claims:
1. The design of Ballastless Track with Indigenous Fastening System (BLT-IFS) for running of trains with maximum axle load of 25T with speed upto 110 kmph with components has unique and innovative features for washable apron on platform lines & non platform lines at stations, in tunnels, on bridges & viaduct for use in Indian Railways.

2. The following components of BLT-IFS and specification as attached are claimed to be as original and innovative items in this reference:

i. General arrangement of BLT-IFS along with fixing arrangement with the reinforcement concrete slab is as per Drawing no. RDSO/T-8305.
ii. The canted Precast Rail Seat beams (PCRSB)(Drawing no. RDSO/T-8304)
iii. The Base rubber pad of 10 mm thickness (Drawing No. RDSO/T-8299)
iv. SGCI flat bearing plate with two shoulders casted for holding Elastic rail clips (Drawing No. RDSO/T-8307)
v. Transition Arrangement from ballasless to ballasted track on embankment (Drawing No. RDSO/T-8301)
vi. Transition Arrangement from ballasless to ballasted track in tunnel/viaduct (Drawing No. RDSO/T-8418)
vii. 10mm thick base plate pad for tunnel & viaduct (Drawing No. RDSO/T-8420)
viii. 10mm thick rail pad for transition for tunnel & viaduct (Drawing No. RDSO/T-8419)

3. This BLT-IFS design along with components listed in para 2 above, is economical and will serve the purpose of ballastless track effectively for washable apron on platform at stations.& non-platform lines at stations, in tunnels, bridges & viaduct under Indian Railways conditions.