Installation Guideline
Under Sleeper Pads (USP)
for Concrete Sleepers
1. Transport and Storage— Always transport in original packaging— Damaged packaging shall be immediately repaired(using plastic foil and adhesive tape)— Storage should be in a dry environment in original
packaging— Protection from direct sunlight is preferred— Once the original packaging is removed, USP must bekept dry— Temperatures below -20 °C and above +50 °C should beavoided— Do not stack pallets and parcels— USP are subject to normal thermal expansion/
shrinking. This physical effect is completely reversible— Storage conditions (and temperature) should match
installation conditions; in case of big temperature
differences between storage and production area, it’srecommended to condition/temper USP for at least 24 h
— Shelf life of Getzner USP is not limited: if storedcorrectly, the USP can stay in storage for years to beinstalled at any later point in time.

2. Assembly of Under Sleeper during
Production of Padded Sleepers

Flock connection layer

Protection layer (optional)

Elastic layer

2.1 Production of padded concrete sleepers
Sleeper manufacturing methods (e.g. instant demoulding,late demoulding, etc.) vary greatly between different
sleeper producers and factories. The experts at Getzner
Werkstoffe have vast experience with these different
production methods. Prior to the first production of padded
sleepers it is recommended to coordinate with Getzner toassist in the first trials to achieve the best possible results.
Getzner uses two different connection layers for its USP:
flock and mesh connection layer.

Mesh connection layer

Protection layer (optional)

Elastic layer

Attention: Please note that in case of bonding the USP
Pads with Diisocyanate containing bonding agents, staff
needs to be trained and certified conform EU legislation
2020/1149. More information you can find via link https://safeusediisocyanates.eu/.

www.getzner.com

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Installation Guideline
Under Sleeper Pads (USP)
for Concrete Sleepers

The two connection layers are exchangeable, nevertheless, if producing padded sleepers for the first time with anyof the two connection methods, it is recommended to execute some trial productions.
The following steps shall serve as a guideline, the list of steps is non-exhaustive and depending on actual production
methods:

Firstly the sleeper mould is filled with concrete.

The concrete is compacted by means of electric concrete
vibrators, either placed at the bottom or on top of the mould.
The method depends on the actual sleeper manufacturing
process.

Spacers or centering pins (optional, depending on production method) are placed in order to prevent USP
from being completely embedded into the concrete andto keep USP in correct position. It is up to the sleeper
manufacturer to ensure proper placement maintaining
the correct distances to the outer contour of the sleeper.
Under no circumstances shall the USP be longer/wider
than the sleeper!

2Installation Guideline
Under Sleeper Pads (USP)
for Concrete Sleepers

Two USP are placed onto the flat concrete surface withthe connection layer (mesh or flock) facing downwards,
being in direct contact with the wet concrete.

By means of a stiff load distribution plate, covering thewhole surface of the pad, the connection layer (meshor flock) is fully embedded into the fresh concrete. It is
recommended to use vibrating motors on the load
distribution plate to enable the best connection between
USP and sleeper.

Sleeper
USP

Sleeper

Sleeper

USP

USP

Due to the different consistencies of the concrete, theUSP can be embedded in slightly varying depths. We
recommend to fully embed the connection layer plus
2 — 4 mm of the elastic layer to ensure the best connection
between USP and concrete sleeper.

Execution of fillet depending on production method

Then, after the appropriate concrete curing time, thepadded sleeper can be installed in track.

3Installation Guideline
Under Sleeper Pads (USP)
for Concrete Sleepers

2.2 Quality control of the assembly— High concrete coverage of theUSP: after placing the USP on thewet concrete and vibrating once
more (preferably from the top), theUSP is lifted to check the concrete
coverage: USP surface covered inconcrete versus total USP surface.
A concrete coverage of ≥ 70 % isdesirable.
— Concrete
coverage
shall
bedocumented with photos during
trial productions.

— The edge distance between outer
contour of sleeper and outer
contour of USP is jointly agreed
upon with the client (refer toillustration below). This ensuresthat USP are not damaged duringtamping.
— Testing the quality of the connection
is done by pull-out testing. The
test is executed according to thestandard EN 16730.
— The quantity of sleepers that has

to be tested depends on the daily
production quantity of the sleeper
manufacturing plant, Deutsche Bahn
(German federal railways) standard
requires the following:1) 1 % of the daily production quantity2) If daily quantity is < 150 sleepers:
one sleeper per day3) If daily quantity is < 250 sleepers:
two sleepers per day4) For turnout sleepers: 1 sleeper per
80 running metres

Length of USP

Under Sleeper Pad
Edge of concrete sleeper

Width ofUSPxx

Exemplary dimensions of USP and concrete sleeper

3. Adhesive Bonding of Under Sleeper Pads

In the case of already produced
sleepers, the USP can be retrofitted
by bonding them to the sleeper.
For this application, the USP areexclusively delivered without meshor flock.
3.1 Adhesive
The adhesive is provided together
with the USP by Getzner Werkstoffe.
Please follow the safety data sheet
and instructions for use to ensure
correct handling.
3.2 Sleeper
The bonding surface of the sleeper
has to be dry and clean. It should be4

rather level and smooth (the rougher,
the more adhesive is required). The
surface may not have depressions.
3.3 Bonding
Sleeper is placed upside down andthe surface is cleaned if necessary.
Prepare the adhesive as described in
the instructions for use. Please mind
temperature and pot life of the adhesive. The prepared adhesive is puton the ballast side of the sleeper. If
the pad is divided in parts, the joints
also have to be bonded. The required
amount of adhesive is determined by
the roughness of the concrete surface.

Typically an amount of 0.5 — 2 kg ofadhesive is used per sleeper. The
USP is then placed centrically on thesleeper. During curing time the padshall be evenly loaded on the wholesurface with at least 50 kg. After bonding, there should be no cavities,
which are not filled up with adhesive.
The total thickness of the adhesive
layer should not exceed 5 mm because
the stiffness of the system could beinfluenced.

Installation Guideline
Under Sleeper Pads (USP)
for Concrete Sleepers
4. Storage of Padded Sleepers
Usually padded concrete sleepers are stacked on top ofeach other and stored outside.

USP types with max. number of stacked sleepers:(assumed sleeper weight: 300 kg)

The stacking capacity of padded sleepers is generally
limited by the static load limit of the material. Themaximum amount of sleepers to be stacked is determinedby a laboratory test procedure (according to the standard
EN 16730).

SLS: max. 15 sleepers
SLN: max. 15 sleepers
SLB: max. 15 sleepers

Specific values for the maximum number of stackedsleepers are dependent on the sleeper weight and the sizeof the spacer that is used between the sleepers because
both determine the specific load on the elastic material.
The wooden spacers resting on the rail seats between any
two sleepers should be as wide as possible, a minimumof 100 mm is absolutely required. The exact amount ofsleepers that can be stacked depends on the USP type
and the sleeper type.
Padded sleeper
Spacer5

5. Transport of Padded Sleepers

7. Disclaimer

Attention has to be paid during transportation toavoid mechanical damage.

This guideline only serves to support the customer or
his authorised specialist in the installation of Getzner
USP. Getzner Werkstoffe draws the attention to known
demands and problems. This guideline was compiled
with the utmost care based on Getzner’s current
knowledge.
Due to the large number of different construction
designs and requirements, Getzner Werkstoffe accepts
no liability for the completeness of the installation
guideline. In particular, Getzner Werkstoffe is not
responsible for the proper installation of Getzner USP
and the resulting negative effects on the condition/ quality of Getzner USP or its performance. It isrecommended that the installation is carried out bya specialist.
All other rights are reserved! Sharing withunauthorised third parties is expressly prohibited.

6. Lifetime and Recycling
USP made from Sylomer® and Sylodyn® materials
are long-lasting elastomers. The lifetime of the USP
matches the lifetime of the sleeper, which means: noUSP has to be exchanged prior to the exchange ofthe sleeper.
At the end of the lifetime of a padded concrete
sleeper the USP can be peeled off the sleepersmechanically
andbethermallyrecycled.
Unused USP or pieces thereof can be recycled
in standard plastics waste containers. All ourmaterials are non-hazardous to the environment.

30+years

AUSTRIA — Bürs GERMANY — Berlin — Munich — Stuttgart FRANCE — Paris — Lyon JAPAN — Tokyo
INDIA — Pune CHINA — Beijing USA — Charlotte AUSTRALIA — Melbourne
www.getzner.com
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Installation Guideline USP Concrete Sleeper EN © Copyright Getzner Werkstoffe GmbH | 07-202

Installation Guideline
Under Sleeper Pads (USP)
for Concrete Sleepers