References

RET Rotterdam plans renewal of the tracks in the Zaagmolenstraat.

After installation of the new track, a new vehicle, the “Citadis II” will be put into service. RET wants to know the effects of these changes on the transmission of vibrations to the dwellings along the line.

At RET’s request, both the recommended criteria/limits as well as existing vibration levels (before the renewal) were taken into account and compared. To this end, a reference measurement (or zero measurement) was also executed.

Design and engineering of vibration protection in the high speed line between Palencia and León. The study included a measurement campaign along the over 110 km long alignment.

Line 1 – North extension
Manila (PH)

D2S International is noise and vibration consultant (client side) for the new extension connecting the current Yellow line with the Blue Line. The activities included preparation of the tender specifications with respect to the trackworks.

The noise and vibration study entailed the analysis of the existing noise and vibration levels from tram passages, the prediction of the future noise and vibration levels, the design of a floating slab system for the narrow section of the Brusselsesteenweg (between Keizerspoort and Hoveniersstraat) in order to reduce the vibrations to acceptable levels.

Design of noise and vibration mitigation measures for the new high-speed line Motilla del Palancar – Valencia and Benifaió – Valencia for trains running at 250 to 350 km/h and vibration study in the line: Motilla del Palancar – Valencia. The study included an extensive noise and vibration measurement campaign and site surveys along the over 140 km long alignment.

The objective of this contract was to evaluate the vibration impact of the High Speed Train Line between Olmedo-Zamora, which consists of 107 km of double high-speed track. The objective was to avoid any risk on complaints or problems in the nearby buildings during exploitation.
D2S International made an analysis of the applicable standards and regulations, a FEM modelling of the track systems, a vibration prediction and finally a selection both budgetary and technically of possible mitigation measures.

D2S International is in charge of the noise and vibration studies for this project consisting of 64 km tracks from which 20 km at European side and 44 km at the Asian side. This study included a major noise and vibration measurement campaign in over 250 sites. In a second stage of this study, optimal protection is determined for sensitive areas and buildings, including noise screens and special measures for viaducts and stations.

The vibration levels in the buildings in the immediate surroundings of the future tracks were estimated using highly conservative assumptions in order to determine the zones where more detailed studies were needed. This study included vibration measurements at grade and inside some buildings close to the existing lines, vibration propagation measurements through the different types of soil and numerical procedures for extrapolation of the measurement results to the future line. The estimated vibration levels have been summarised in coloured maps.

Definition of the required vibration mitigation characteristics of the tracks along the entire alignment in order to comply with the specific vibration criteria of this project.

Control of ground borne noise and vibration levels in a number of sensitive areas, due to the passages of ERL and CRS trains, including the study of some specific zones verification of the vibration levels at the foot of the columns near the tracks at KL Sentral and control of the ground borne noise and vibration levels in the offices above the tracks at Putrajaya station.

Noise and vibration (including ground borne noise) study of the GLT (Guided Light Transport) for both road & rail vehicle. This study ran from the pre-project phase until the verification measurements in exploitation.

Identification and quantification of rail corrugation with Rail Surface Analyser from APT (Alfa Products & Technologies) in order to compare these results with the limits in the ProRail-directive (01/04/2009 – REF RLN00065).

Preliminary study for drafting the DBFM contract and IES: noise and vibrations
This noise and vibration study was part of the preliminary study of the Pegasus plan Livan 1, Tramway line Turnhoutsebaan – Wommelgem – N12. The goal was to characterise the current situation, with regard to noise and vibration in the areas around the tunnel and its surroundings, the open trench slope and at the grade section. These results led to a set of specifications that was included in the tender documents for DBFM contract.
The study covered the following aspects:
 the outlining of the normative framework;
 the characterisation of the current noise and vibration situation;
 the calculating of the future vibration levels;
 the drafting of set of specifications.

Comparison of the benefits of two different vibration mitigating track types. The vibration levels in 8 buildings along two future metro lines were predicted by means of numerical modelling. The conclusions formed the basis of the decision on the selection of the solution that had to meet the local Andalusian environmental regulations.

This comprehensive noise and vibration study for this partly at grade extension included the selection of the rail fixation system to limit transmission of ground borne noise and vibrations into the adjacent buildings. This was the first application of direct rail fixation on concrete for the Brussels metro. The characteristics of the rail fixation as well as the areas requiring floating slab were determined.

A complete noise and vibration impact study was made for two new metro lines. The new lines are constructed in a tunnel in non-homogeneous soil and under a large number of sensitive historical buildings. This study involved the determination of the appropriate rail fixation on a concrete trackbed. Noise and vibration calculations were carried out for buildings along both lines, using modelling procedures, which involve finite element analysis. The twin block system with rubber boots and undersleeper pads with a specific dynamic stiffness was selected as an appropriate system to isolate vibrations and ground borne noise. This study showed a.o. that it was not necessary to install expensive floating slabs. The noise and vibration levels in the environment were predicted with high accuracy as was confirmed with verification measurements in the Concert Hall building.

The north/south Line Department of the city of Amsterdam contacted D2S International for expert advise and assistance regarding noise, vibrations and track dynamics. D2S International complied an inventory of the buildings along the line, performed initial measurements of noise, vibrations and vibration induced noise, and made predictions of the impact on these buildings with the appropriate mitigation measures. These aspects were included in the building specifications for the design build project and created a normative framework.

Design and engineering of vibration protection in the high speed line between Valladolid and Palencia. The study included a measurement campaign along the over 30 km long alignment.

Design and engineering of noise mitigation measures and vibration study along the new high-speed line between Caudete and Alicante. The major included an extensive measurement campaign and site surveys along the over 70 km long alignment.

The scope of this report is the determination and evaluation of the noise and vibration levels coming from the trains running in the tunnel. Two tunnel sections were studied in detail: a station section longitudinally centred at shallow depth in the avenue, a deeper standard tunnel section located beneath the water table and close to building foundations. The LVT track system was considered for both sections.

D2S International is responsible for the ground borne noise and vibration study of the future tramlines in downtown Palermo. The lines will operate vehicles of the Bombardier Flexibility Outlook series. The study includes the design of vibration mitigation measures.

In a first step of the project, a multi body model was created of the track and vehicle to calculate the forces between the rail and wheels during the passage of a vehicle over a particular track section.
In a second step, a finite element model (FEM) of the rail, fastener and anchorage was created to calculate the stresses in the assembly. Those stresses were compared with the maximum allowable stresses in order to predict if a failure in one of the components would occur or not.

A noise and vibration study for the new mixed traffic (high speed, regional and freight) trainline in the southwest of the city centre of Malaga was performed. The aim of the study was to identify critical areas along the alignment (including tunnels and open cut tracks) and to define all mitigation measures required, at the track level, in order to avoid any noise and vibration annoyance in nearby buildings during exploitation.

10 years after previous study (see above), similar study for new extensions of both metrolines, with a detailed study of special trackwork.

Noise and vibration impact study of a projected 10 km long tunnel for trains running at 160 and 230 km/h between Paris East Station and Charles de Gaulle International Airport.

Ground borne noise and vibration study along the line, taking into account different rail fixation types. Detailed studies inside and outside stations equipped with special trackworks.

Noise and vibration control of the environment; acoustic design of stations.

This project involved a vibration analysis of the metro network. Verification with the selected rail fastening system was carried out in order to ensure compliance with the criteria of the vibration levels and the structure borne noise in the buildings.

The project consists of two phases.
Phase 1: Study of 8 different track systems in the tunnel for the high-speed line underground junction on the high-speed line between Sants and La Sagrera station in Barcelona. Calculation of vibration levels inside buildings along the alignment. Special attention was paid on the Sagrada Familia, which is very close to the alignment. The study included a measurement campaign of the vibration propagation in buildings along the alignment around the Sagrada Familia and transfer mobility measurements in the soil close to the Sagrada Familia
Phase 2: Control measurements of the vibration levels in buildings along the alignment after the completion of tunnel for calibration of the model. Two types of vehicle were used for the study: an Alstom S103 car and a Siemens 252 locomotive.

D2S International performed an investigation of the vibration problems occurring in the buildings along the high-speed train tunnel in Vilafranca del Penedés.
The tunnel consists of 1300 m double-ballasted track and is located next to a conventional rail tunnel. D2S International made a complete analysis of the problem and traced back the vibration problems with a modal analysis of the tunnel. Recommendations were given to change the tunnel structure and track system in order to avoid the vibration problems.

This noise and vibration study involves the construction of a passage between Sants and La Sagrera in the centre of Barcelona. The aim of the study is to define all mitigation measures required, at the track level, in order to avoid any noise and vibration annoyance in nearby buildings during exploitation. In the project, air born noise and vibrations were considered for the open track sections, ground borne noise and vibrations for the tunnel sections.

Assistance to Spie for all vibration issues related to the track numerical simulations following a methodology imposed by the final customer, determination of required track stiffnesses in order to comply with criteria imposed by the final customer, technical support for lab tests of the track components.