FREQUENTLY ASKED QUESTIONS


1. Why signal-layered membrane should be used in tunnel implementations? What is working system of signal layer?

Signal layer used in tunnels is a light-colored (yellow and white etc.) laminated layer on PVC membrane with approximately 0.7 mm thickness and makes contribution to inner tunnel enlightenment to determine visually laceration and perforation which may occur on the membrane in the examination. Due to high volume of tunnels, it is not possible to reach insulation layer and examine whole structure in case of any damage on insulation material. Signal layer allows sectional renovation by emerging of high-colored membrane in sub-layer due to exposure of damaged area to penetration.


2. How and How offer material conformity test are performed?

Material conformity tests are performed by General Directorate of Highways Laboratories (Ankara) by taking sample under control of engineers authorized by Highways Directorate from all lots submitted to the building site. It is so important for the implementing company that test results are archived until temporal and precise acceptance of the results and, submitted to competent authorities where necessary. In case of emerge of damage it will constitute problem in material conformity registration.


3. How PVC membrane welding is performed? Is welding torch an appropriate method?

After surface conformity conditions for PVC implementations are fulfilled (see implementation technical specification) whole area where 500 gr/m2 geotextile 7-10 cm overlap is applied shall be fixed be means of strings. After covering by welding by means of strings used in placement of internal surface of the tunnel with help of Multiplan BAT PVC membrane welding machines, Multiplan BAT 7-10 cm overlap is applied and seam welding process is started using a seam welding fusion robot. After applying seam welding carefully, it is combined with material coming from base and therefore insulation is completed. Material is non-utilizable as welding torch burns and melts material.


4. What is the difference of frame used in tunnel implementation from others?

Frames used in new constructions and building restorations in our environment comply with standards and are appropriate for usage of the same frames for different fields provided that they maintain necessary width and height after attachment of parts assembled on building surface. In tunnel frames production is made dedicatedly by making static calculations according to spring height of every tunnel.


5. What dimensions have PVC membrane rolls and is roll height of standard?

Multiplan BAT tunnel pvc membranes are produced at requested dimensions as axis-striped in center and overlap-stripped in edges according to spring height for providing convenience during application.


6. What are advantages of Multiplan BAT signal layered tunnel membranes?

Multiplan branded products recipes are prepared by Multiplan Germany and audited in independent and accredited laboratuaries regularly. Raw materials used in the production are 100% original and recyclable and environment-friendly products. Procurement of rolls in dimension demanded as per tunnel diameter additional to rolls sizes provides opportunity for fast and economical application. Multiplan transfers its millions of square meter sale and application experience.


7. What are accessory properties required to be utilized in the application?

Strings used in the application shall comply with pvc membrane. Metal strings are not used on tunnel coverings and strings shall be pvc based to fix immobilize materials. Geotextile felt shall be produced from 100% polypropylene material with minimum 500gr/m2.


8. How should nailguns used in fixing strings be?

Two types nailguns (pneumatic and gunpowder) are used. As pneumatic nailguns can work well in humid environment, they are more preferred than gunpowder nailguns.