Modular Slab Track. Asfordby Slab Installation IVES PORR V-Tras. PWI Winter Conference December

Transcription

1 Modular Slab Track Asfordby Slab Installation IVES PORR V-Tras PWI Winter Conference December

2 Development of the Modular concept Although many forms of slab track have been developed it can be argued that the birthplace of high speed slab system is Japan JNR started to develop new track structures, the design specification being Ø Construction cost being less than twice that of ballasted track Ø Elasticity and lateral/vertical strength be greater than that of ballasted track Ø Construction rate of >200m per day In 1972 the ballastless track structure was named Slab Track and first applied on the Sanyo Shinkansen line

3 Development of the Modular concept Ø Slab dimensions 5m x 2.2m x 0.19m Ø Stopper gives lateral stability

4 Life Cycle Cost

5 Life Cycle Cost

6 Continued Development Many variations have since been developed as well as alternative slab systems Standard Frame Slabs - Japan Rheda Germany

7 Continued Development Bogl - Germany PORR - Austria

8 Asfordby Network Rail made the decision to undertake a trial of two slab track forms in 2013 with the addition of a new form of transition module Ø System 1 Rhomberg Sersa IVES

9 System specifics Asfordby

10 Asfordby

11 Asfordby

12 Ø System 2 PORR Asfordby

13 Asfordby

14 Asfordby Ø Transition Module Rhomberg Sersa V-Tras

15 Asfordby

16 Asfordby

17 Asfordby LH Curve radius 1655m 70m transition 180m straight 50m transition LH Curve radius 1785m V-Tras 165 IVES Blocks 24 PORR Slabs 209 IVES Blocks

18 Sequence of works; Ø Formation prepared with 100mm of Type 1 material compacted to achieve a minimum stiffness of 30kN/mm Ø Using standard highways asphalt machine (laser controlled) lay two layers of hot rolled asphalt, total depth is 250mm with a minimum width of 2700mm Tolerance of Asphalt layer +0mm / -10mm Asfordby

19 Installation of IVES; Asfordby Ø IVES blocks are lifted and placed on the Asphalt layer Total accuracy of the vertical and horizontal alignment is not required at this stage.

20 Asfordby Ø Baseplates are laid in readiness for rail installation

21 Ø Rails are installed and clipped up Ø RhoTas system is installed Ø Rail and Baseplate are lifted and aligned to the final design Asfordby

22 Asfordby Ø Rails are installed and clipped up Ø RhoTas system is installed Ø Rail and Baseplate are lifted and aligned to the final design Ø Hergie measuring system is used to measure the track position / gauge / super elevation Ø Accuracy of +/- 1mm is achievable

23 Ø Shutters are fitted to the Baseplates Ø Grout is poured through the grout aperture to fill the void below the Baseplate Asfordby

24 Installation of PORR; Asfordby Ø PORR slabs are lifted and placed on the Asphalt layer Ø Wire mesh is laid / supported 50mm above the Asphalt layer Ø Five threaded support bars hold the slab to design height

25 Ø Reinforcement cages are fitted in the slab recesses Ø Shuttering is fitted to the sides of the slab Ø Rails are installed and clipped up Ø Final design is achieved by adjusting the threaded support bars Asfordby

26 Ø Self Compacting Concrete is poured to fill the void below the slab Asfordby

27 Asfordby Installation V-Tras; Ø Concrete slab is cast to hold the pivot rail

28 Asfordby Installation V-Tras; Ø V-Tras unit is lifted into place

29 Asfordby Installation V-Tras; Ø V-Tras is lifted to final design Ø Sleepers are placed on V-Tras Ø Ballast is placed and compacted in layers

30 Asfordby Installation V-Tras; Ø Rail is installed and clipped up Ø Adjustment made to the horizontal alignment Ø Horizontal alignment is fixed Ø V-Tras is lifted to final vertical alignment and ballast compacted

31 Summary of Benefits Simple and robust structure Ø Use existing sub structure Ø Standard asphalt / concrete formation layer Ø Single design of pre stressed concrete bearer for straight and curved track Ø Low surface pressure Fast and simple construction Ø Simplicity and robustness of the bottom up system with accuracy of the top down rail positioning Ø Only the final rail positioning requires time consuming accuracy Ø Mechanised construction Ø Single line working construction Ø Simple and effective surface drainage Ø Low surface pressure

32 Summary of Benefits Efficiency in design Ø Long term track stability Ø Designed and managed track stiffness Ø Improved track drainage eliminates drainage faults such as wet beds Ø Low ground bearing forces Ø High accuracy of rail positioning with long term stability of the rail geometry thus reduction a in track component failure.

33 Summary of Benefits Efficiency in operation Ø Line speed handback Ø Increased infrastructure performance Ø Reduced impact on operational running Ø Reduced faults Ø ballast deterioration Ø drainage failure Ø reduced rail wear therefore increased rail life (+25%) Ø eliminates maintenance interventions Ø reduced renewal interventions Ø increase in S+T performance Ø System will allow for track lowering in tunnels for gauging or OLE installations fixed geometry allowing reduced gauge clearances