4.4 Propose solutions after preliminary theoretical assessment

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1 TIP4-CT Page 1 of 17 DELIVERABLE D 4.7 CONTRACT N TIP4-CT PROJECT N FP ACRONYM QCITY TITLE Quiet City Transport Subproject 4 Noise propagation and receiver perception Work Package 4.4 Propose solutions after preliminary theoretical assessment Prototype of improved noise barrier Written by Henrik Malker & Nils-Åke Nilsson ACL Bo Samuelsson Date of issue of this report PROJECT CO-ORDINATOR Acoustic Control ACL SE PARTNERS Accon ACC DE Akron AKR BE Amec Spie Rail AMEC FR Alfa Products & Technologies APT BE Banverket BAN SE Composite Damping Material CDM BE Havenbedrijf Oostende HOOS BE Frateur de Pourcq FDP BE Goodyear GOOD LU Head Acoustics HAC SE Heijmans Infra HEIJ BE Royal Institute of Technology KTH SE Vlaamse Vervoersmaatschappij DE LIJN LIJN BE Lucchini Sidermeccanica LUC IT NCC Roads NCC SE Stockholm Environmental & Health Administration SEA SE Société des Transports Intercommunaux de Bruxelles STIB BE Netherlands Organisation for Applied Scientific Research TNO NL Trafikkontoret Göteborg TRAF SE Tram SA TRAM GR TT&E Consultants TTE GR University of Cambridge UCAM UK University of Thessaly UTH GR Voestalpine Schienen VAS AU Zbloc Norden ZBN SE Union of European Railway Industries UNIFE BE PROJECT START DATE February 1, 2005 DURATION 48 months Project funded by the European Community under the SIXTH FRAMEWORK PROGRAMME PRIORITY 6 Sustainable development, global change & ecosystems ZBN Deliverable doc

2 TIP4-CT Page 2 of 17 EXECUTIVE SUMMARY A special low noise barrier has been developed especially for tram applications. A screen designed for the new Sirio Tram for Gothenburg has been manufactured, where size and choice of colour has been specially adapted. Earlier within the QCITY project it was shown, through measurements on a functional prototype (not for installation on the tram network), that the Insertion loss of this screen type is IL = db(a). This functional prototype has now been developed to a product ready to be installed on a Tram network, see picture below. Deliverable doc

3 TIP4-CT Page 3 of 17 TABLE OF CONTENTS 1 Objectives and scope of work Design Manufacturing Insertion Loss Discussion Deliverable doc

4 TIP4-CT Page 4 of 17 1 OBJECTIVES AND SCOPE OF WORK The objective has been to develop an improved noise barrier for tram applications. The new improved noise barrier is of the type low close fitting screen. It has the size and placement more like a platform than a normal screen.

5 TIP4-CT Page 5 of 17 2 DESIGN The first design is shown in Figure 1. It was designed for the new Sirio trams from AnsaldoBreda at the Gothenburg Tram Network, which has a white and blue colour. Therefore these designs have been either blue as shown in Figure 2 or the complementary colour to that blue, which is the red (or Maroon) showed in Figure 1. Selecting the blue colour would give the drawback to be very sensitive to nuances in the blue colour. Only a blue colour that is exactly the same blue nuance as on the tram will look good. The complementary colour is less sensitive to colour nuance mismatches. The junction between two elements is made like two matching rounded surfaces. This ensures interlocking between the elements and it is also possible to introduce an angle (maximum 45 o ) between the elements. This is shown in the appended drawing. Absorbent Anti-slip Rubber mat The junction between two elements Perforated steel Painted concrete Figure 1. Sketch of one of the first design propositions. Notice the way the two elements interlock through the curved shape.

6 TIP4-CT Page 6 of 17 The sound absorbent is encapsulated in the protecting perforated steel, which also fastens it to the concrete body. Figure 2. Sketch of one of the first design propositions in blue colour. Notice the perforated steel that protects the sound absorbent and fastens it to the conrete body. Perforated steel of 1.5 mm thickness to resists the load of a grown man. Figure 3. The final proposed design solution for the prototype. The colour and small design changes can be adapted to meet custumers demand.

7 TIP4-CT Page 7 of 17 The noise screen is 300 mm high. Mounted close to a low floor tram of the type found in Gothenburg, Athens and many other places (e.g. the Sirio tram from AnsaldoBreda) will result in a very efficient sound reduction treatment. Figure 4. shows the screen design together with the Gothenburg Tram. Figure 4. Sketch of the prototype noise screen together with the Gothenburg Sirio Tram car.

8 TIP4-CT Page 8 of 17 3 MANUFACTURING Two prototypes have been manufactured to be able to show the interlocking and angling function between two screen elements. The manufacturing is here described step by step. The perforated steel for protecting the sound absorbent is bent into shape, see Figure 5. The perforated steel plate is of 1.5 mm thickness to withstand the load that could be expected on the track site. Figure 5. The perforated steel is bent into shape. The absorbent is thereafter place inside the shaped perforated steel as shown in Figure 6. Notice the excess part of the perforated steel that is angled 45 o. This part of the perforated steel plate is cast to form an integral unit with the screen concrete body.

9 TIP4-CT Page 9 of 17 Figure 6. The sound absorbent is encapsulated in the perforated steel sheet. Figure 7 shows the two step back part of the casting mould. Figure 7. The back of the mould is made out of plywood and wood. Notice the spherical pieces of wood that will produce the dimple effect on the vertical parts of the screen.

10 TIP4-CT Page 10 of 17 Below in Figure 8 is the assembling of the casting mould shown. First the rounded end parts are fastened. Then the sound absorbing front is mounted and the last step the two step moulds are mounted. Figure 8. Pictures showing the assembling of the mould. At the top is the two rounded end parts. Then to the left the sound absorbent front part is mounted and last to the right the two step back part is mounted in the mould.

11 TIP4-CT Page 11 of 17 Before casting reinforcement iron was put into the cast, as shown in Figure 9. Then the mould was filled with the concrete. Figure 9. Pictures showing the reinforcement iron and casting process. Part of the reinforcement iron is bent out side the mould to work as simple lifting handles. These are cut and anti-rust treated after the screen has been lifted out of the mould. Figure 10. Picture showing the casting process. Notice the simple lifting handles.

12 TIP4-CT Page 12 of 17 Below in Figure 11 the concrete screen is lifted out of the mould. Figure 11. Picture showing the first concrete screen element being lifted out of the casting mould. After the screen has been lifted out and turned around (during casting the screen is upside down) removable lifting eye bolt are mounted to move the screens in place, see Figure 12. The threaded hole is left in place making it easy to move the screen. Figure 12. Removable lifting eye bolt to move the screens in place.

13 TIP4-CT Page 13 of 17 Threaded holes for lifting eye bolts enables the screen element to be moved by a crane. Figure 13. First concrete screen on the ground. In Figure 14 below two unpainted screen elements are shown. An anti-slip rubber mat is mounted on the top surface. Also visible on the picture is the interlocking between the two elements through the rounded ends.

14 TIP4-CT Page 14 of 17 1 cm gap (elastically sealed) between screen elements to allow for ground movements etc. Figure 14. The two prototype screen elements unpainted with an anti-slip mat mounted on the top. This is an alternative if the buyer doesn t want the screens painted. The elements can also be painted as shown in the design sketches (Figure 3 and Figure 4). The best paint for these kinds of applications is a silicate based paint. These high quality paints are not delivered or sold in small batches. For the prototypes an alternative environmentally resistant paint has been applied it is called Stocryl v100 and usually used for concrete floors on balconies. The final design proposal of the prototypes in red painted version are shown in Figure 15 and Figure 16.

15 TIP4-CT Page 15 of 17 Figure 15. The back side of the two final painted screen elements joint together. Figure 16. The front side of the two final painted screen elements joint together.

16 TIP4-CT Page 16 of 17 4 INSERTION LOSS Earlier within the QCITY project measurements on a functional prototype low screen for tram (see Figure 17) showed an Insertion Loss of IL = db(a). Figure 17. Low close fitting screen functional prototype. Picture from measurements performed by TTE and TRAM in Athens on functional protypes from Z-Bloc designed by Acoustic Control.

17 TIP4-CT Page 17 of 17 5 DISCUSSION In producing these screen elements Z-Bloc Norden has shown that it is possible to manufacture screens that look close to the earlier presented design sketches. These screen elements are merging together an attractive design, still maintaining the sound reduction that was shown during measurements in Athens on the early functional prototype. The now presented screen prototype is a finished product almost ready for the market. The design allow for a great deal of flexibility in shape in colour so that it can be adapted to the specific costumer needs. The prototype screen shown here could be expected to provide an Insertion Loss of IL = db(a) units.