Case Study
Improvement of Track Quality
at Daqin Coal Line, China

Reduction of maintenance costs

Elongation of tamping cycles

Increase of life time of the trackImprovement of track quality
and lower deterioration rates

Project Description
The heavy haul network in China isexpanding fast. With total mileageof 653 km the DatongQinhuangdao(short: “Daqin”) coal line is the major corridor for transporting coalfrom the west (Shanxi and Shaanxi
provinces and the Inner Mongolian
Autonomous Region) to Qinhuangdao, China's largest coal-exportingseaport.
Increased track availability, especially in heavy haul railway lines,
is the target of many research anddevelopment projects on and off thetrack for many years. Using elastic
polyurethane components in the ballasted track system reduces track
maintenance and therefore increases the availability of the line.

Daquin’s double-track electrified line with an axle load of 25
tonnes opened in december 1992 andis capable of transporting a total volume of 450 MGT/year. To ensure thatthe superstructure would be able tocope with these high numbers, an
extra-wide subgrade and significantly stronger rails (75 kg/m) were usedto ensure proper load distribution.
The technology meets international
standards: it was China's first heavy
haul railway to use a computerised
centralised traffic control system andthe first line in the country to use an
optical fibre communication system.

Based on the breakthroughs implemented in this line, China was able to
make substantial progress in heavy
haul railway transportation.
Cost drivers on the open track
Heavy haul route operators are facedwith a number of challenges. With itsvery high frequency of trains (100 to130 trains per day with daily gross tonnage up to 1.3 MGT), the operators require a highly durable superstructure.
Damages to the components and increased wear caused by heavy traffic
would reduce availability of the route,increase the maintenance requirements and drive up operating costs.
Also, destruction of ballast is common
on heavy haul lines due to the exceptionally high loads. This causes damage to many essential superstructurecomponents such as breaking of railclips and sleepers. Only if the ballast,which is the weakest link in the ballasted track, remains intact, the quality of the entire system is preserved
and superstructure components suchas rails and sleepers are subjected toless stress.
Reducing loads on ballast
Decreasing the load on the ballast canbe achieved in two ways: by increasing
the size of the contact area between
the sleeper and ballast and throughimproved load distribution over therail.
Adding elasticity to the superstructure
prevents individual components frombeing overloaded. Elastic Rail Pads under the rail foot significantly improve
the load distribution. Under Sleeper
Pads can amplify this effect and also
increase the contact area between thesleeper and ballast. Using Under Ballast Mats is another way of introducing a defined level of elasticity into thesuperstructure. In addition, they relieve the interface between the ballast
bed and hard subgrades.

Advantages— Better track availability
and less track possessions— Lower deterioration rates
therefore decrease ofmaintenance requirements— Operation of a durable
track system with lower
life-cycle costs (LCC)— Positive influence on thelateral track resistance— Less damage tosuperstructure components— Track quality andgeometry at a high level

Destroyed ballast, rail clips and sleepers due to inhomogeneously embedded sleepers

By conducting comprehensive statistics
and analyses of the track geometry maintenance costs were reduced and several
positive effects were witnessed since theapplication of Getzner USPs.
The Getzner solution
Installation of elasto-plastic
Under Sleeper Pads (USPs)

To counteract degrading superstructure, Getzner approachedseveral heavy haul networks within
China to install and test elasto-plastic
USPs. Along the Daqin coal line, twosections were selected and in 2016
the Taiyuan Railway Bureau applied
polyurethane USPs to both tracks(loaded and unloaded directions).
The loaded, padded section has a total length of 1.46 km at the mileageof km 296 + 700 ~ km 298 + 160. The
section includes a curve, three bridges (total length 375.9 m) and threetunnels (total length 277 m). In orderto prove the benefits of the elastic
superstructure, this track with frequent changes of subgrade conditions (open track/tunnels/bridges)
was predestined. The elasto-plastic SLB 2210 G and the slightly moreelastic SLB 1510 G USP types were
carefully selected by Getzner’s engineering department, keeping in mind
all boundary conditions of the test
track.
No damages or maintenanceFourteen months after the installation, the total tonnage amounted
to 519 MGT. Within this time theunpadded section had been tamped
twice during major maintenance undertakings, whilst the padded section
showed no need of tamping or maintenance at all. On top of this, no other defects such as fractured sleepers
or rail clips, white spots or hanging
sleepers could be detected within
the padded section. The track quality
and geometry were kept at a very
high level.
Durable and economical tracksystem
With the installation of polyurethane
USPs of types SLB 2210 G andSLB 1510 G on the Daqin coal line,

maintenance activity was dramatically reduced. This saves money
and significantly increases the track
availability. Until today the padded
track needed no tamping with USPs
(compared to four times without),
even after more than 1000 MGT. The
use of USPs in the track superstructure enables the operation of a durable low life-cycle cost track system
for China's heavy haul network.

Daqin LineNJiningHohhot

Daqin LineBaotou

Beijing

DatongTianjin

Shenchi

Bo HaiShuohShenmu
Xinzhou

Qinhuangdao
Qian‘anuang

RailwayHuanghua
Cangzhou

Facts and figures

Axle loads on theheavy freight line:

1.46 km of Under Sleeper Pads
Taiyuan Railway Bureau
Under Sleeper Pads of type SLB 1510 G and SLB 2210 G(at the transition, 25 m at each side)
25 metric tons and total tonnage of 1000 MGT

Getzner Werkstoffe GmbHFoundation:
Chief Executive Officer:
Employees:
2018 turnover:Business areas:
Headquarters:
Locations:
Ratio of exports:

1969 (as a subsidiary of Getzner, Mutter & Cie)Ing. Jürgen Rainalter
490 (360 in Bürs)
EUR 100.3 million
Railway, construction, industry
Bürs (AT)
Berlin (DE), Munich (DE), Stuttgart (DE), Lyon (FR), Amman (JO), Tokyo (JP),Pune (IN), Beijing (CN), Kunshan (CN), Charlotte (US), Decatur (US)93 %AUSTRIA — Bürs GERMANY — Berlin — Munich — Stuttgart FRANCE — Lyon
JAPAN — Tokyo INDIA — Pune CHINA — Beijing USA — Charlotte

JORDAN — Amman
www.getzner.com

CS DaQin Coal Line en © Copyright by Getzner Werkstoffe GmbH | 05-2019

Line mileage (over which
the material was installed):
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