Due to increasing traffic flows the extension of transport infrastructure with rail roads and high speed lines is an ongoing process worldwide. Ballastless track systems with concrete slabs are used more and more.
Following the first trials in the 1970s and more than four decades of R&D work on ballastless track, the level of development is such that it can be confirmed that ballastless track is suitable for use as an alternative to ballasted track. This book makes a contribution to the state of the art of ballastless track by describing the basics for designing the ballastless track. Important advice is provided regarding the construction of ballastless track on earthworks and in tunnels. There is also a description of the technical history of the development of ballastless track on bridges and the ensuing findings for bridge design. The state of the art of ballastless track for switches, important information on details concerning drainage, transitions, accessibility for road vehicles and experience gleaned from maintenance round off the work.
Selected chapters from the German concrete yearbook are now being published in the new English "Beton-Kalender Series" for the benefit of an international audience.
Since it was founded in 1906, the Ernst & Sohn "Beton-Kalender" has been supporting developments in reinforced and prestressed concrete. The aim was to publish a yearbook to reflect progress in "ferro-concrete" structures until - as the book's first editor, Fritz von Emperger (1862-1942), expressed it - the "tempestuous development" in this form of construction came to an end. However, the "Beton-Kalender" quickly became the chosen work of reference for civil and structural engineers, and apart from the years 1945-1950 has been published annually ever since.
Table of Contents:
Editorial IX
About the authors XI
1 Introduction and state of the art 1
1.1 Introductory words and definition 1
1.2 Comparison between ballasted track and ballastless track 1
1.3 Basic ballastless track types in Germany – the state of the art 3
1.3.1 Developments in Germany 4
1.3.2 Sleeper framework on continuously reinforced slab 5
1.3.3 Continuously reinforced slab with discrete rail seats 7
1.3.4 Precast concrete slabs 7
1.3.5 Special systems for tunnels and bridges 9
1.3.6 Further developments 9
1.3.7 Conclusion 11
1.4 Ballastless track systems and developments in other
countries (examples) 11
References 15
2 Design 17
2.1 Basic principles 17
2.1.1 Regulations 17
2.1.2 Basic loading assumptions 18
2.2 Material parameters – assumptions 19
2.2.1 Subsoil 19
2.2.2 Unbound base layer 20
2.2.3 Base layer with hydraulic binder 21
2.2.4 Slab 23
2.3 Calculations 24
2.3.1 General 24
2.3.2 Calculating the individual rail seat loads 24
2.3.3 Calculating bending stresses in a system with continuously supported track panel 28
2.3.4 System with individual rail seats 28
2.3.5 Example calculation 32
2.4 Further considerations 35
2.4.1 Intermediate layers 35
2.4.2 Temperature effects 35
2.4.3 Finite element method (FEM) 36
References 37
3 Developing a ballastless track 39
3.1 General 39
3.2 Laboratory tests 40
3.2.1 Rail fastening test 40
3.2.2 Testing elastic components 41
3.2.3 Tests on tension clamps 42
3.3 Lateral forces analysis 42
References 43
4 Ballastless track on bridges 45
4.1 Introduction and history 45
4.1.1 Requirements for ballastless track on bridges 45
4.1.2 System-finding 45
4.1.2.1 Geometric restraints 47
4.1.2.2 Acoustics 48
4.1.2.3 Design 48
4.1.3 System trials and implications for later installation 49
4.1.4 Measurements during system trials 50
4.1.4.1 Braking tests 50
4.1.4.2 Acoustic properties after installing a resilient mat 50
4.1.4.3 Deflection of the slab 51
4.1.4.4 Summary of system trials 51
4.1.5 Regulations and planning guidance for laying ballastless track on bridges 51
4.1.6 The Cologne–Rhine/Main and Nuremberg–Ingolstadt lines 51
4.1.7 VDE 8 – new forms of bridge construction 52
4.2 Systems for ballastless track on bridges 53
4.2.1 The principle behind non-ballasted ballastless track on long bridges 53
4.2.2 Ballastless track components on long bridges 54
4.2.2.1 Rail seats 54
4.2.2.2 Slab 56
4.2.2.3 Cam plate 56
4.2.2.4 Separating layer 57
4.2.2.5 Protective concrete 58
4.2.3 Ballastless track on short bridges 58
4.2.4 Ballastless track on long bridges 59
4.2.5 The bridge areas of ballastless tracks 61
4.2.6 End anchorage 62
4.3 The challenging transition zone 62
4.3.1 General 62
4.3.2 The upper and lower system levels 62
4.3.3 Interaction of superstructure and bridge 63
4.3.4 General actions and deformations at bridge ends 64
4.3.5 Summary of actions 66
4.3.6 Supplementary provisions for ballastless track on bridges and analysis 66
4.3.7 Measures for complying with limit values 68
4.3.8 Summary, consequences and outlook 69
References 70
5 Selected topics 73
5.1 Additional maintenance requirements to be considered in the design 73
5.2 Switches in slab track in the Deutsche Bahn network 73
5.3 Slab track maintenance 76
5.4 Inspections 76
5.4.1 General 76
5.4.2 Cracking and open joints 77
5.4.3 Anchors for fixing sleepers 78
5.4.4 Loosening of sleepers 78
5.4.5 Additional inspections 79
5.5 Slab track repairs 79
5.5.1 Real examples of repairs 79
5.5.2 Renewing rail supports 79
5.5.3 Repairing anchor bolts 80
5.5.4 Dealing with settlement 80
5.5.5 Defective sound absorption elements 80
5.6 Drainage 81
5.6.1 General 81
5.6.2 Draining surface water 81
5.6.3 Central drainage 81
5.6.4 Strip between tracks 81
5.6.5 Cover to sides of slab track 82
5.7 Transitions 82
5.7.1 General 82
5.7.2 Transitions in substructure and permanent way 82
5.7.3 Welding and insulated rail joints 83
5.7.4 Transitions between bridges/tunnels and earthworks 83
5.7.5 Transitions between slab and ballasted track 83
5.7.6 Transitions between different types of slab track 84
5.8 Accessibility for road vehicles 84
5.8.1 General 84
5.8.2 Designing for road vehicles 84
5.8.3 Designing for road vehicle loads 85
5.9 Sound absorption elements 86
5.9.1 General 86
5.9.2 Construction and acoustic requirements 86
5.9.3 Special requirements for materials and construction 86
References 87
Index 89
