ICS 91.010.30; 93.040

ROMANIAN STANDARD

SR EN 1991-2/NB

December 2006

Eurocode 1: Actions on structures

Part 2: Traffic loads on bridges.National Annex

Eurocod 1: Acţiuni asupra structurilor. Partea 2: - Acţiuni din trafic la poduri. Annex naţională

Eurocode 1 : Actions sur les structures – Partie 2 : Actions

sur les ponts, dues au trafic. Annexe Nationale

APPROVAL Approved by the Director General of ASRO on December 2006

ROMANIAN STANDARDS ASSOCIATION (ASRO) 21-25 Mendeleev Street, cod 010362, Bucharest ROMANIA

General Director: Phone: +40 21 316 32 96, Fax: +40 21 316 08 70 Director of Standardization Division: Phone: +40 21 310 17 30, +40 21 310 43 08, +40 21 312 47 44, Fax: +40 21 315 58 70

Sales Department – Subscriptions Department: Phone: +40 21 316 77 25, Fax + 40 21 317 25 14, +40 21 312 94 88 Marketing Editorial Staff- Copyright Department: Phone: +40 21 316.99.74

© ASRO Entire or partial multiplication or use of this standard in any kind of publications and by any means (electronically, mechanically, photocopy, micro media etc.) is strictly forbidden without a prior written consent of ASRO

Ref.: SR EN 1991-2:2004/NB:2006 Edition 1

Foreword This standard SR EN 1991-2:2004/NB:2006 represents national annex NB which defines the conditions of application for SR EN 1991-2:2004 for territory of Romania. This National Annex has been prepared by the Technical Committee CT 343 “Basis of Design and Structural Eurocodes” of ASRO, the Secretariat of which is held by INCERC (National Institute for Building Research), under the authority of the Ministry of Transports, Constructions and Tourism. Relevant Authoritys:

- For railway bridges –Art and Ground Works Department of National Railway Company „CFR” – S.A.

- For road bridges and over-passes – National Highways and National roads Company in Romania

The National Annex gives data regarding the Nationally Defined Parameters, alternative procedures, values and classes, according to the provisions of the standard SR EN 1991-2:2004 regarding the approval of some national options for the following items:

- 1.1(3); - 2.2(2) note 2, 2.3(1), 2.3(4); - 3(5); - 4.1(1) note 2, 4.1(2) note 1, 4.2.1(1) note 2, 4.2.1(2), 4.2.3(1), 4.3.1(2) note 2, 4.3.2(3) notes 1 şi 2,

4.3.2(6), 4.3.3(2), 4.3.3(4) note 2, 4.3.4(1), 4.4.1(2) note 2, 4.4.1(3), 4.4.1(6), 4.4.2(4), 4.5.1 – table 4.4a notes a şi b, 4.5.2 note 3, 4.6.1(2) note 2, 4.6.1(3) note 1, 4.6.1(6), 4.6.4(3), 4.6.5(1) note 2, 4.6.6(1), 4.7.2.1(1), 4.7.2.2(1) note 1, 4.7.3.3(1) note 1, 4.7.3.3(1) note 3, 4.7.3.3(2), 4.7.3.4(1), 4.8(1), 4.8(3), 4.9.1(1) note 1

- 5.2.3(2), 5.3.2.1(1), 5.3.2.2(1), 5.3.2.3(1)P note 1, 5.4.(2), 5.6.1(1), 5.6.2.1(1), 5.6.2.2(1), 5.6.3(2) note 2, 5.7(3);

- 6.1(2), 6.1(3), 6.1(7), 6.3.2.(3)P, 6.3.3(4), 6.4.4, 6.4.5.2(3), 6.4.5.3(1), 6.4.5.3 table 6.2, 6.4.1.1(6), 6.4.6.1.1(7), 6.4.6.1.2(3) table 6.5, 6.4.6.31(3) table 6.5, 6.4.6.3.2(3), 6.4.6.3.3(3) notes 1 şi 2, 6.4.6.4(4), 6.4.6.4(5), 6.5.1(2), 6.5.3(5), 6.5.3(9)P, 6.5.4.1(5), 6.5.4.3(2) notes 1 şi 2, 6.5.4.4(2) note 1, 6.5.4.5, 6.5.4.5.1(2), 6.5.4.5.1(2), 6.5.4.6 note, 6.5.4.6.1(1), 6.5.4.6.1(4), 6.6.1(3), 6.7.1(2)P, 6.7.1(8)P, 6.7.3(1)P, 6.8.1(11)P table 6.1, 6.8.2(2) table 6.11, 6.8.3.1(1), 6.8.3.2(1), 6.9(6), 6.9(7);

- Annex C(3)P, Annex C(3)P, Annex D2(2) This national annex is only to be used together with the standard SR EN 1991-2:2004 to establish the imposed loads due to the road, passenger and railway traffic for the designing of new bridges, including abutments, piles, reverted walls, guard walls as well as their foundations. Romanian standard SR EN 1991-2:2004 can be used in both for private and public sector in the art works domain. The following are excepting: art works for which there are other stipulations in the design and performance contract document for which supporting documents are to be provided and must be approved by the relevant Authorities and by the control Authorities in constructions.

The values of the safety partial coefficients and for different designing situations are determined according to the provisions in standards SR EN 1990:2002, and EN 1990:2004/A1:2006 and their national annexes. Up to the complete implementation in Romania of the full set of Eurocodes (EN 1990 up to EN 1999) by publishing the Romanian standards taking them over, as well as their national annexes, the Nationally Defined Parameters can be defined, for each project separately, as needed. Numbering the articles in the National Annex is identical with that in SR EN 1991-2:2004.

SR EN 1991-2:2004/NB:2006

I. Nationally Determined Parameters for the used of the standard SR EN 1991-2:2004

Section 1 General

1.1(3) Complementary rules for retaining walls buried structures and tunnels In particular cases, at the beneficiary’s request and with the agreement of relevant Authority, complementary rules can be utilized, which shall be included into the Specifications (the individual project).

Section 2 Classification of Actions

2.2(2) NOTE 2: Use of the infrequent values of loading for road bridges The representative values of the traffic loads and pedestrian loads are the following:

- Characteristic values, established either statistically with a limited probability of being exceeded during the bridge design working life, or nominally, according to the provisions 4.1.2(7) of SR EN 1990:2002;

- Frequent values;

- Quasi-permanent values.

Calibration of the main Load Models for road bridges and footbridges is according to Table 2.1 of SR EN 1991-2:2004. In particular cases, when the conditions defined in note 2 of 2.2(2) are fulfilled, with the beneficiary’s and

the relevant authority agreement, the infrequent values of the loads are used for the road bridges.

2.3(1) Definition of appropriate protection against collisions The protection systems against collisions shall be justified provided in the Specifications.

2.3(4) Rules concerning collisions forces from various origins. Recommended values of the forces due boats or ships against the main structure of the road or railway bridges are taking from EN 1991-1-7. In particular cases, the beneficiary with agreement of the relevant authority, can specify other values of the collisions forces which are specified in the Specifications.

Section 3 Design situations

5 Rules for bridges carrying both road and rail traffic In case of combined bridges, the simultaneity of actions and the special verifications taken into account for the design are established by the beneficiary and approved by the relevant authority. These provisions are mentioned in the Specifications.

Section 4 Road traffic actions and other actions specifically for road bridges

4.1(1) NOTE 2: Road traffic actions for loaded lengths greater than 200 m. Load models for loaded length greater than 200 m, and their associated loads, are established by the

beneficiary, with the agreement of the relevant authority. The provisions are mentioned in the Specifications.

SR EN 1991-2:2004/NB:2006

2

4.1(2) NOTE 1: Specific load models for bridges which limitation of vehicles weight For the bridges placed on the local, agricultural or private roads etc, equipped with road signs intended to limit the vehicle weight and/or the axle weight, the beneficiary with the agreement of the relevant authority, can establish special loads and their associated rules that are mentioned in the Specifications.

4.2.1(1) NOTE 2: Definition of complementary load models If the foreseen traffic exceeds the limits of the load models specified in Section 4 of SR EN 1991-2:2004 the complementary load models and the associated combination rules shall be taking into account. The complementary load models shell be approved by the beneficiary and the

relevant authority and will be included in the Specifications.

4.2.1(2) Definition of models of special vehicles. For the special load models that do not comply with the required conditions concerning limits of weights and dimensions or for military loads special load models are provided for special vehicles, complying with the provisions in Annex A of SR EN 1991-2:2004.

4.2.3(1) Conventional height of the kerbs The minimum height of the kerbs is 100 mm. In particular cases, beneficiary, with agreement of the relevant authority, can establish other values of the kerbs height, which are specified in the Specifications.

4.3.1(2) NOTE 2: Use of LM 2 To cover the normal traffic effects on short structural members, in the range of lengths up to 3 m to 7 m, the Load Model 2 shall be used (LM 2).

4.3.2(3) NOTES 1 and 2 Values of factors

If not otherwise mentioned, the factors Qi , qi and qi are taken equal to 1,0. In particular cases, at the beneficiary’s request, based on traffic studies issued by an authorized

domain institution, with the agreement of the relevant authority, other values of the factors Qi, qi and

qi can be adapted, which are specified in the Specifications.

4.3.2(6) Use of simplified alternative load models. The provisions in 4.3.2(6) in SR EN 1991-2:2004 are applied.

4.3.3(2) Values of factor

The value of Q factor is taken equal to Q1. In particular cases, the beneficiary, with the agreement of the relevant authority, can establish other

value for the Q factor, which is specified in the Specifications.

4.3.3(4) NOTE 2: Selection of wheel contact surface for LM 2 The wheels contact surface of the Load Model 1 and 2 are taken into account as in figure 4.3, indicated in SR EN 1991-2:2004. In particular cases, beneficiary with agreement of the relevant authority, can establish for both Load Models square contact surfaces, which are specified in the Specifications

SR EN 1991-2:2004/NB:2006

3

4.3.4(1) Definition of Load Model 3 (special vehicles) The Load Models for special vehicles as well as the associated rules are given in annex A of SR EN 1991-2:2004. In particular cases, beneficiary with agreement of the relevant authority, can establish other load models

for special vehicles, as well as their application rules, which are specified in the Specifications.

4.4.1(2) NOTE 2: Upper limit of the braking force on road bridges. The upper limit of the braking force for the road bridges is of 900 kN. The lower limit of the braking force for the road bridges is not be less than of 300 kN. In particular cases, beneficiary with agreement of the relevant authority, can establish other limits for the braking/acceleration force, which is mentioned in the Specifications.

4.4.1(3) Horizontal force associated with Load Model 3 For Load Model 3, beneficiary, with agreement of the relevant authority can establish the horizontal force

associated to this load model, which is specified in the Specifications.

4.4.1(6) Braking force transmitted by expansion joints. The horizontal force transmitted by the expansion joint or applied to structural members that can be loaded by only one axle is considered according to expression (4.6a) from SR EN 1991-2:2004.

4.4.2(4): Lateral forces on road bridges decks The lateral force at the road bridges decks is taking according to the provisions 4.4.2(4) of SR EN 1991-2:2004. In particular cases, beneficiary with agreement of the Relevant Authority, can establish other value of the lateral force which is specified in the Specifications.

4.5.1 Table 4.4a NOTES a and b Consideration of horizontal forces in gr1a a – The provisions in 4.4.1 and 4.4.2 respectively of SR EN 1991-2:2004 are applied. b – The recommended value is: 3 kN/m

2.

In particular cases, beneficiary with the agreement of the relevant authority, can establish other value of the

uniform distributed force which is specified in the Specifications.

4.5.2 NOTE 3: Use of infrequent values of variable actions In case of taking into account of infrequent values of the variable actions rule 4.5.1 is used, replacing all the characteristic values in table 4.4a with the infrequent values as defined in SR EN 1990:2004/A1:2006, leaving unchanged the other values mentioned in the Table.

4.6.1(2) NOTE 2: Use of fatigue load models The Fatigue Load Model 1 is used to check when the maximum stress range is beyond the value of the unlimited designed life. The correction factors are taken complying with the provisions in 4.6.2(1). The Fatigue Load Model 2 is used to check the unlimited fatigue life, in the same way as in case of Fatigue Load Model 1. In case the Fatigue Load Model 3 do not lead to a satisfactory insurance for the fatigue life time assessment designed by cumulating the damages the Fatigue Load Model 4 is to be used. The conditions to use the Fatigue Load Models no. 1, 2, 3 and 4, as specified in SR EN 1991-2:2004,

SR EN 1991-2:2004/NB:2006

4

accepted by the beneficiary, and agreed by the relevant authority are mentioned in the Specifications.

4.6.1(3) NOTE 1: Definition of traffic categories. The traffic categories as well as the values Nfat are taken from table 4.5n, presented in SR EN 1991-2:2004. In particular cases, beneficiary with agreement of the relevant authority, can establish other values for Nfat,

which are specified in the Specifications.

4.6.1(6) Definition of additional amplification factor (fatigue) It applies expression (4.7) from SR EN 1991-2:2005. In particular cases, beneficiary with the agreement of the relevant authority, can establish other value for the additional dynamic amplification factor which is specified in the Specifications.

4.6.4(3) Adjustment of Fatigue Load Model 3. The conditions of application of Fatigue Load Model 3 is considered complying with the provisions in 4.6.4(3), NOTE from SR EN 1991-2:2004. In particular case, beneficiary with the agreement of the relevant authority, can establish other rules of application of the Fatigue Load Model 3 which is specified in the Specifications.

4.6.5(1) NOTE 2: Road traffic characteristics for the use of Fatigue Load Model 4 Fatigue Load Model 4 consists of a set of standard lorries defined in Tables 4.7 and 4.8 of SR EN 1991-2:2004. In particular cases, beneficiary with the agreement of the relevant authority, can establish other standard lorries as well as their percentages which are specified in the Specifications.

4.6.6(1) Use of Fatigue Load Model 5 The Fatigue Load Model 5 is only used at the beneficiary’s request, having also the agreement of the

relevant authority, only if the traffic records are available and of recent date.

4.7.2.1(1) Definition of impact force and height of impact At the beneficiary’s request with the agreement of the relevant authority, the protection systems for the bridge

infrastructure against vehicles collision can be provided; the efficiency of the protection system is supported by calculations or experience. For the stiff piers, the following minimum values of the collision forces are recommended:

a) Impact force: 1000 kN in the vehicle direction or 500 kN perpendicular on that direction; b) The height where this force is applied: 1.25 m from the running surface.

See also EN 1991-1-7. Beneficiary, with the agreement of the relevant authority, can establish other values of the collision forces as well as their application height, which are specified in the Specifications.

4.7.2.2(1) NOTE 1: Definition of collision forces on decks. Preventive or protective measures are the most efficient against the collision force: rigid structures placed before and after the bridge or warning systems providing sound and/or light alarms, in case a vehicle having abnormal or illegal height for the under-bridge clearance is running on the road. The preventive and protective systems shall comply with the conditions provided in the Specifications

SR EN 1991-2:2004/NB:2006

5

and are approved by the beneficiary and by the relevant authority. See also EN 1991-1-7.

4.7.3.3(1) NOTE 1: Definition of collision forces on vehicle restraint systems The class of the collision forces and the application conditions are selected out of Table 4.9(n) presented in 4.7.3.3 Notes 1 and 2 of SR EN 1991-2:2004. The horizontal force acts transversally, is applied on 0.5 m load length, at the lower level selected between: 100 mm under the top of the selected vehicle restraint and 1.0 m above the surface of the running level of the vehicles or above the sidewalk.

4.7.3.3(1) NOTE 3: Definition of vertical force acting simultaneously with the horizontal collision force

The vertical force acting simultaneously with the horizontal collision force is: 0.75Q1Q1k.

4.7.3.3(2) Design load for the structure supporting a vehicle parapet The structure supporting the vehicle parapet are designed to sustain locally an accidental load effect corresponding to at least 1.25 times the characteristic local resistance of the vehicle parapet (such as the resistance of the connections of the parapet to the structure) and need not be combined with any other variable load.

4.7.3.4(1) Definition of collision forces on unprotected vertical structural members When designing the unprotected structural members placed above or under the carriageway level the vehicle collision force as defined in 4.7.2.1(1) is taken into account, acting at 1.25 m above the carriageway level. These forces can be reduced, having the agreement of the relevant authority, if protective systems between the carriageway and the structural members are provided.

4.8(1) NOTE 2: Definition of actions on pedestrian parapets. When designing the pedestrian parapets a uniformly distributed longitudinal force of 1.0 kN/m, considered that a horizontal or vertical load at the upper level of the pedestrian parapet for footways or footbridges. For service side paths is taken a 0.8 kN/m force. These minimal recommendations do not cover the exceptional and accidental cases.

4.8(3) Definition of design loads due to pedestrian parapets for the supporting structure Were pedestrian parapets cannot be considered as adequately protected against vehicle collision, the supporting structure shall be designed so as to be able to sustain an accidental load effect corresponding of 1.25 times the characteristic resistance of the parapet, exclusive of any other variable load.

4.9.1(1) NOTE 1: Definition of load models on embankments. When designing the bridge elements, which are in contact with earth, the Load Model 1 (LM1) will be used, as presented in 4.3.2 din SR EN 1991-2:2004. To simplify, the tandem system is replaced with an equivalent uniformly distributed load qeq, spread on a rectangular surface. The loads dispersal through the backfill are comply with the provisions in EN 1997. In case the backfill is properly consolidated, the value of the dispersal angle from the vertical

is equal to 30. With such a value for the angle, the surface on which the qeq load is applied is a rectangular surface 2.20 m long and 3.0 m wide.

SR EN 1991-2:2004/NB:2006

6

Section 5 Actions on footways, cycle tracks and footbridges

5.2.3(2) Definition of load models for inspection gangways The used model is that which produces the most unfavourable effects between an uniform distributed load of 2 kN/m

2 and a concentrated force of 3 kN applied on a square surface having the following

dimensions: (0.20 x 0.20) m2.

5.3.2.1(1) Definition of the characteristic value of the uniformly distributed load. The characteristic value of the uniformly distributed load qfk is: 5 kN/m

2.

Beneficiary, with agreement of the relevant authority, can establish other value of the uniformly distributed force qfk , which is specified in the Specifications.

5.3.2.2(1) Defining of the characteristic value of the concentrated load on footbridges The characteristic value of the concentrated load Qfwk is 10 kN acting on a square surface of sides 0.10 m. Beneficiary, with the agreement of the relevant authority, can establish other value for the concentrated load Qfwk or for the surface on which it acts which is specified in the Specifications.

5.3.2.3(1) P NOTE 1: Definition of service vehicles for footbridges If the characteristics of the service vehicles are not given in the Specifications, they are considered as identical with those defined in 5.6.3(2) in SR EN 1991-2:2004. In this case, the respective vehicle needs not be considered as accidental load.

5.4(2) Characteristic value of the horizontal force on footbridges If no other values of the horizontal force are given in the Specifications, they are taken according to 5.4(2) of SR EN 1991-2:2004.

5.6.1(1) Definition of specific collision forces. Depending the real situation in the location and on the operational conditions, the accidental collision forces – their value and application model - are provided in the Specifications. The characteristics of the collision forces have the agreement of the beneficiary and the relevant authority.

5.6.2.1(1) Collision force on piers. At the beneficiary’s request with the agreement of the relevant authority, the protection systems for the bridge infrastructure against vehicles collision can be provided; the efficiency of the protection system is supported by calculations or experience. For the stiff piers, the following minimum values of the collision forces are recommended:

a) Impact force: 1000 kN in the vehicle direction or 500 kN perpendicular on that direction; b) The height where this force is applied: 1.25 m from the running surface.

See also EN 1991-1-7. Beneficiary, with the agreement of the relevant authority, can establish other values of the collision forces as well as their application height, which are specified in the Specifications.

5.6.2.2(1) Collision force on decks Preventive or protective measures are the most efficient against the collision force: rigid structures placed before and after the bridge or warning systems providing sound and/or light alarms, in case a vehicle having abnormal or illegal height for the under-bridge clearance is running on the road.

SR EN 1991-2:2004/NB:2006

7

The preventive and protective systems shall comply with the conditions provided in the Specifications and are approved by the beneficiary and by the relevant authority. See also EN 1991-1-7.

5.6.3.(2) NOTE 2: Definition of a load model for accidental presence of a vehicle on a footbridge If the Specifications do not specify otherwise, the characteristics of the vehicle presented in figure 5.2 (5.6.3(2)) in SR EN 1991-2:2004 are to be taken into consideration.

5.7.3 Definition of dynamic models of pedestrian loads. The structure configuration shall be chosen so as the natural frequencies (corresponding to horizontal, vertical and torsion vibrations) of the structure are outside the domains mentioned at note 5.7.(2). Unless otherwise mentioned in the Specifications, the comfort criteria are comply with the provisions in SR EN 1990:2004/A1:2006.

Section 6 Rail traffic actions and other actions specifically for railway bridges

6.1(2) Traffic outside the scope: EN 1991-2, alternative load models In particular cases, when the traffic outside the scope of the load models specified in this Section 6 of SR EN 1991-2:2005, the beneficiary, with the agreement of the relevant authority, can specify alternative load models and associated combination rules, which are specified in the Specifications.

6.1(3) Other types of railways Beneficiary, having the agreement of the relevant authority can specify the load models and associated combination rules for the types of railways presented in 6.1(3) of SR EN 1991-2:2004, which are mentioned in the Specifications.

6.1(7) Temporary bridges The temporary bridges are designed taken into account the principles and provisions of SR EN 1991-2:2004. Special requirements that they shall comply with, depending on the conditions in which they are used, are specified in the Specifications drawn up by the beneficiary and approved by the

relevant authority.

6.3.2(3)P Value of factor

The value of factor is equal to 1.0. If along the influence line cannot be placed at the most one single axle of the load model LM 71, the

value of factor is taken equal to 1.1.

In particular cases, beneficiary with agreement of the relevant authority, can specify other value of factor, which is specified in the Specifications.

6.3.3(4) Choice of lines for heavy rail traffic The railway lines or section of line over which heavy rail traffic run are established by the relevant

authority for the Romanian Railways and are specified in the Specifications.

6.4.4 Alternative requirements for a dynamic analysis. The requirements for determining whether a static or a dynamic analyses is required are used the flow chart in Figure 6.9 of SR EN 1991-2:2004.

SR EN 1991-2:2004/NB:2006

8

6.4.5.2(3) Choice of dynamic factor

It is used 3 factor.

Beneficiary, with the agreement of the relevant authority may specify the use of dynamic factor 2, and it is

specified in the Specifications.

6.4.5.3(1) Alternative values of determinant length The determinant length is taken according to provisions in Table 6.2. of SR EN 1991-2:2004.

6.4.5.3 Table 6.2 Determinant length of cantilevers All cantilevers supporting railway traffic loads longer than 0.5 m are studied according to 6.4.6 and with the loading agreed with the relevant authority specified in the National Annex.

6.4.6.1.1(6) Additional requirements for the application of HSLM The provisions 6.4.6.1.1 of SR EN 1991-2:2004 are applied.

6.4.6.1.1(7) Loading and methodology for dynamic analysis. For particular designing situations, the loads and methodology for the dynamic analysis, approved by

the relevant authority, are given in the Specifications.

6.4.6.1.2(3), Table 6.5 Additional load cases depending upon number of tracks For bridges on which the trains run with speed higher than 200 km/h, which sustain three or more track, beneficiary with the agreement of the relevant authority, issue provisions referring to loads and their combination which are specified in the Specifications.

6.4.6.3.1(3) Value of damping. For the structures dynamic analysis the alternative minimum damping values to be considered are those values indicated in the last column of Table 6.6 (for spans L ≥ 20 m) in SR EN 1991-2:2004.

6.4.6.3.2(3) Alternative density values of materials. For the dynamic analyses, when designing the bridges structures, the minimal and maximal values of the concrete density are taken into consideration as given in EN 1991-1-1. In particular cases, for important structures, intermediary values of the concrete density can also be taken into consideration, if they lead to some more unfavourable effects.

6.4.6.3.3(3) NOTES 1 and 2: Enhanced Young’s modulus. Other material properties For the dynamic analysis, when designing the bridge structures, the minimal and maximal values of the concrete Young’s modulus presented in EN 1992 up to EN 1994 . In particular cases, for important structures, the intermediary values of the concrete Young’s modulus can be also taken into consideration if they lead to more unfavourable effects.

6.4.6.4(4) Reduction of peak response at resonance and alternative additional damping values The used method, agreed by the beneficiary and the relevant authority is “step by step integration method”. The value of the integration step is chosen so as the numeric errors resulted from truncating of the mathematical operations do not affect the calculation accuracy in a significant way. The minimal values of the damping are taken according to provisions 6.4.6.3.1(3) of SR EN 1991-2:2004.

SR EN 1991-2:2004/NB:2006

9

6.4.6.4(5) Allowance for track defects and vehicle imperfections. Unless otherwise specified in the Specifications, the used dynamic coefficient is:

"1

where ” ≥ 0 and complies with the provisions in Annex C of SR EN 1991-2:2004.

6.5.1(2) Increased height of centre of gravity for centrifugal forces Beneficiary with the agreement of the relevant authority specifies, in the Specifications, the height (load centre) where the centrifugal force applied, depending on the constructive parameters of the rolling stock.

6.5.3(5) Actions due to breaking for loading lengths greater than 300 m In case the length of the influence line La,b exceeds 300 m, beneficiary with agreement of the relevant authority establishes and mentions in the Specifications, the value of the traction and breaking force, which is used when designing the structure.

6.5.3(9)P Alternative requirements for the application of traction and breaking forces In case of bridges carrying two or more tracks, the traction and braking forces on each of track is taken according to the load situation described in 6.8.1 of SR EN 1991-2:2004.

6.5.4.1(5) Combined response of structure and track, requirements for non-ballasted track Depending on the concrete situation, special requirements referring to the combined response of the structure and track for the bridges with non-ballasted track system, agreed by the beneficiary and the relevant authority are mentioned in the Specifications.

6.5.4.3(2) NOTES 1 and 2: Alternative requirements for temperature range Temperature variations in the structure are considered equal to those recommended in EN 1991-1-5. In particular cases, with agreement of the beneficiary and the relevant authority, alternative values may be adopted, justified by the real situation on site.

6.5.4.4(2), NOTE 1: Longitudinal shear resistance between track and bridge deck The values of the longitudinal resistance for the track/ballast/bridge stiffness analysis, approved by the beneficiary and the relevant authority are specified in the Specifications. The evaluation of the respective resistances are made in studies and researches carried out by a domain institution, endowed with corresponding apparatus, instruments and trained staff with experience in the domain, agreed by the relevant authority.

6.5.4.5 Alternative design criteria Designing criteria adopted for common situations are those presented in 6.5.4.5 of SR EN 1991-2:2004. In particular cases, other designing criteria may be also adopted, other than those in SR EN 1991-2:2004, agreed by the beneficiary and the relevant authority.

6.5.4.5.1(2) Minimum value of track radius For ballasted track or for track directly fastened, the minimum value of the curve radius can be reduced if supplementary measures are taken to prevent the lateral displacements, agreed by the beneficiary and the relevant authority.

SR EN 1991-2:2004/NB:2006

10

6.5.4.5.1(2) Limiting values for rails stresses For track configurations (which may influence its lateral resistance) other than those already mentioned, maximum supplementary stresses in the rail are presented in the Specifications, with the agreement of the beneficiary and the relevant authority.

6.5.4.6 Alternative calculation methods The calculation methods presented in 6.5.4.6.1 and in Annex G of SR EN 1991-2:2004 are applied. Alternative calculation methods can be adopted with the agreement of the beneficiary and the relevant authority, issued by specialized institutions with experience on the domain, based on some corresponding studies.

6.5.4.6.1(1) Alternative criteria for simplified calculations methods The criteria presented in 6.5.4.6.1 of SR EN 1991-2:2004 is applied.

6.5.4.6.1(4) Longitudinal plastic shear resistance between track and bridge deck In case the tracks comply with the requirements presented in 6.5.4.6.1(2) of SR EN 1991-2:2004, the value k is taken from Annex G. In well justified cases, with the agreement of the beneficiary and the relevant authority, other values for k, may be taken.

6.6.1(3) Aerodynamic actions, alternative values The characteristic values of the loads are given from 6.6.2 to 6.6.6 in SR EN 1991-2:2004. In special conditions, with the agreement of the beneficiary and the relevant authority, characteristic values of the aerodynamic actions other than those presented from 6.6.2 up to 6.6.6. may be taken.

6.7.1(2) P Derailment of the rail traffic, additional requirements The designing situations to be taken into considerations are those presented in 6.7.1(2) of SR EN 1991-2:2004.

6.7.1(8) Derailment of rail traffic, measures for structural elements situated above the level of the rails and requirements to retain the derailed train on the structure When it is required by the operation and/or by the situation on site, the beneficiary together with the relevant authority can impose special measures to reduce the consequences of the derailment and/or of the train retaining on the bridge deck. All these are included in the Specifications.

6.7.3(1)P Other actions Loads to be taken into consideration in case of accidental design, other than those mentioned in 6.7.3(1) are specified in the Specifications, agreed by the beneficiary and the relevant authority.

6.8.1(11)P Table 6.10 Number of tracks loaded when checking the drainage and structural clearance When the case, the number of the tracks to be considered loaded when checking the drainage and structural clearance approved by the beneficiary and the relevant authority are specified in the Specifications.

6.8.2(2) Table 6.11 Assessment of groups of load The characteristic values of the groups of load are multiplied by the factors indicated in table 6.11 of SR EN 1991-2:2004.

SR EN 1991-2:2004/NB:2006

11

6.8.3.1(1) Frequent values of multi- component actions For the determination of the frequent values of the actions in each group of load, the factors indicated in table 6.11 of SR EN 1991-2:2004 are applied.

6.8.3.2(1) Quasi-permanent values of multi- component actions The quasi-permanent traffic actions are taken as zero.

6.9(6) Fatigue Load Models, structural life The design working life is 100 years, according to provisions 2.3(1) of SR EN 1990:2002, Table 2.1.

6.9(7) Fatigue Load Models, special traffic When for the railway section where structure is placed on, there are traffic data recorders and prognosis study drawn up by a competent institution, agreed by the beneficiary and the relevant authority, the fatigue checking of the structure may be carried out considering the study results, which are included in the Specifications.

SR EN 1991-2:2004/NB:2006

12

II. Conditions of application of the SR EN 1991-2:2004 Annexes

Annex A - Models of special vehicles for road bridges Annex A remains informative for the purpose of SR EN 1991-2:2004 and its National Annex.

Annex B - Fatigue life assessment for road bridges Assessment method based on recorded traffic

Annex B remains informative for the purpose of SR EN 1991-2:2004 and its National Annex.

Annex C - Dynamic factors 1+ for Real Trains Annex C remains normative for the purpose of SR EN 1991-2:2004 and its National Annex.

C(3)P Dynamic factor The static loads due to the real trains running at v [m/s] are multiplied by:

1+ = 1+’+” , according to the expression (C.1) SR EN 1991-2:2004.

C(3)P Method of dynamic analysis (1) See the provisions at 6.4.6.4(4).

Annex D Basis for the fatigue assessment of railway structures Annex D remains normative for the purpose of SR EN 1991-2:2004 and its National Annex.

D2(2) Partial safety factor for fatigue loading

Value for Ff is 1,00.

Annex E - Limits of validity of Load Model HSLM and the selection of the critical Universal Train from HSLM- Annex E remains informative for the purpose of SR EN 1991-2:2004 and its National Annex.

Annex F - Criteria to be satisfied if a dynamic analysis is not required Annex F remains informative for the purpose of SR EN 1991-2:2004 and its National Annex.

Annex G - Method for determining the combined response of a structure and track to variable actions Annex G remains informative for the purpose of SR EN 1991-2:2004 and its National Annex.

Annex H - Load models for rail traffic loads in Transient Design Situations Annex H remains informative for the purpose of SR EN 1991-2:2004 and its National Annex.

SR EN 1991-2:2004/NB:2006

13

(blank page)

Members of the Technical Committee TC 343 “Basis of Design and Structural Eurocodes” that participated in the development of this standard:

Chairman: Mr. Radu PASCU UTCB– Bucharest

Secretary: Mrs. Mihaela BONTEA INCERC – Bucharest

ASRO representative:

Mrs. Marilena CĂLIN ASRO

Members: Mr. Dan LUNGU UTCB– Bucharest

Mr. Augustin POPĂESCU POPĂESCU SA

Mr. Dan GEORGESCU INCERC – Bucharest

Mr. Dan DUBINĂ UP Timişoara

Mr. Mircea MIRONESCU MIRO GRUP

Mrs. Nicolina ISOPESCU UT Iassy

Mr. Radu PETROVICI PROVEST PROIECT-

Mr. Iacint MANOLIU SRGF Bucharest

Mr. Tudor POSTELNICU UTCB Bucharest

Mr. Dan DUMITRESCU SIGUR CONSTRUCT

Mrs. Liliana CEAUŞU C.N.S.I.P.C.

Mrs. Doina TOMA MTCT-DRC

Mr. Ioan SONEA M.A.I.

Mr. Florea CRÂNGUŞ CILAS Braşov The Romanian version of this standard has been prepared by Mr. Constantin CRISTESCU and Mrs. Ileana PRODESCU from Railway Study and Design Institute, Bucharest. A Romanian standard does not necessarily include the totality of necessary provisions for contracting. Standard users are responsible for its enforcement.

It is important that users of Romanian standards ensure they have the latest edition and all changes.

Information on Romanian standards (enforcement date, changes etc.) are published in the Romanian Standards Catalogue and in the Standards Bulletin.