Eurocod 3: Proiectarea structurilor de oţel Partea 6: Căi de rulare Anexa naţională

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1 ICS ; ; SR EN /NA STANDARD ROÂN.01 Eurocode 3. Design of steel structures. Part 6: Crane supporting structures. National Annex Eurocod 3: Proiectarea structurilor de oţel Partea 6: Căi de rulare Anexa naţională Eurocode 3. Calcul des structures en acier. Partie 6: Chemins de roulement. Annexe Nationale APROVAL Approved by the Director General of ASRO. ROANIAN ASOCIATION OF STANDARDIZATION (ASRO) endeleev Street. no. 1-5, cod 01036, Bucharest General anager: Tel.: , Fax: Direcţia Standardizare: Tel , , , Fax: Publications Department-Serv. Sales/Subscriptions:Tel , Fax , Editorial Service - arketing, Copyright ASRO Reproduction or use of all or part of this standard in any publications by any means (electronic, mechanical, photocopying, microfilming, etc..) Is prohibited unless written consent of ASRO Ref: SR EN :007/NA:011 First edition

2 SR EN :007/NA:01 National foreword This standard is the National Annex NA which defines the conditions of application in Romania of the standard SR EN :007/NA:011 Eurocode 3. Design of steel structures. Part 6: Crane supporting structures. National Annex together with corrigendum EN :007 / AC: 010. This National Annex has been developed within the Technical Committee ASRO / TC 343 Structural Eurocodes Basis of design and whose secretariat is held by ASRO. This National Annex: - Provides nationally determined parameters (NPD) for the following articles of the European standard EN :007 and errata EN :007 / AC: 010, which authorizes national elections, namely:.1.3.(1) Design working life..8() Partial factor γ F,test for crane test loads. 3..3(1) Lowest service temperature for indoor crane supporting structures. 3..3(1) Selection of toughness properties for members in compression. 3..4(1) table 3. Requirement Z Ed for through-thickness properties. 3.6.(1) Information on suitable rails and rail steels (1) Information on special connecting devices for rails. 6.1(1) Partial factors γ i for resistance for ultimate limit states (1) Alternative assessment method for lateral-torsional buckling 7.3(1) Limits for deflections and deformations. 7.5(1) Partial factor γ,ser for resistance for serviceability limit states. 8.(4) Crane classes to be treated as high fatigue. 9.1() Limit for number of cycles C 0 without a fatigue assessment. 9.(1) Partial factors γ Ff for fatigue loads. 9.() Partial factors γ f for fatigue resistance (1) Crane classes where bending due to eccentricity may be neglected. 9.4.(5) Damage equivalence factors λ dup for multiple crane operation. - sets the conditions for use of normative Annex A of the Romanian standard SR EN :007 and you were SR EN :007 / AC: 010. SR EN :007 / NA: 011, EN :007 and EN :007 / AC: 010 is used in conjunction with the Eurocodes EN 1990 to EN 1999, as the adoption and implementation of these standards in Romania national annexes. The name and numbering of articles of national annex are identical to that of the Romanian standard :007 and corrigendum EN :007 / AC: 010. This national annex belongs to ASRO/CT343 heritage, General rules and rules for buildings.

3 SR EN :007/NA:01 I. Parameters determined at national level to use SR EN :007 and corrigendum SR EN :007 / AC: 010 Basis of design.1.3. Design working life (1) The design working life of a crane supporting structure should be specified as the period during which it is required to provide its full function. The design working life should be documented (for example in the maintenance plan). Note: The National Annex may specify the relevant design working life. A design working life of 5 years is recommended for runway beams, but for runways that are not intensively used, 50 years may be appropriate. The recommended values will be used, taking into consideration the remark that for HC1 and HC crane supporting structures a design working life of 50 years can be considered..8 Crane tests () The ultimate limit state verifications specified in 6 should also be satisfied under the crane test loads, applied at the positions affected. A partial factor γ F,test should be applied to these test loads. Note: The numerical value for γ F,test may be defined in the National Annex. The value of 1,1 is recommended. The recommended values for factor γ F,test will be used. 3 aterials 3..3 Fracture toughness (1) See 3..3(1) and () of EN Note: The lowest service temperature to be adopted in design for indoor crane supporting structures may be given in the National Annex. The recommended values indicated in the National Annex SR EN :006/NA:008, at paragraph 3..3.(1): a) the lowest exploitation temperature for structures without termic protection is the lowest emplacement temperature for a recurrence period of 50 years (T 0 50); b) the lowest exploitation temperature for termic protected structures will be determined with the relation: T 0 = T where: T 0 is the lowest exploitation temperature; T 0 50 is the lowest emplacement temperature for a recurrence period of 50 years (T 0 50); () For components under compression a suitable minimum toughness property should be selected. Note: The National Annex may give information on the selection of toughness properties for members in compression. The use of table.1 of EN for σ Ed = 0,5 f y (t) is recommended.

4 No additional provisions are available Through thickness properties (1) See 3..4(1) of EN SR EN :007/NA:01 Note : The National Annex may specify the allocation of target values Z Ed according to 3.(3) of EN to the quality class in EN The allocation in table 3. is recommended for crane supporting structures. Table 3. Choice of quality class according to EN Target value of Z Ed according to EN to 0 1 to 30 > 30 No additional provisions are available Rail steels Required value of Z Rd according to EN (1) Purpose-made crane rails and railway rails should both be made from special rail steels, with a specified minimum tensile strengths of between 500 N/mm² and 100 N/mm². Note: The National Annex may give information for suitable rails and rail steels, pending the issue of appropriate product specifications (EN product standards, ETAGs or ETAs). No additional provisions are available Special connecting devices for rails (1) Special connecting devices for rails, including purpose made fixings and elastomeric bearing pads should be suitable for their specific use according to the relevant product specifications. Note: The National Annex may give information for special connecting devices, where no appropriate product specification (EN product standard, ETAG or ETA) exists. No additional provisions are available. Z 15 Z 5 Z 35 6 Ultimate limit states 6.1 General (1) The partial factors γ for resistance apply to the various characteristic values in section 6 as indicated in table 6.1. Table 6.1 Partial factors for resistance a) resistance of members and cross-section: resistance of cross-sections to excessive yielding including local buckling resistance of members to instability assessed by member checks γ 0 γ 1

5 SR EN :007/NA:01 resistance of cross-sections in tension to fracture γ b) resistance of joints resistance of bolts resistance of rivets resistance of pins at ultimate limit states resistance of welds resistance of plates in bearing slip resistance: at ultimate limit state (category c) at serviceability limit state (category b) bearing resistance of an injection bolt resistance of joints in hollow section lattice girders resistance of pins at serviceability limit states preload of high strength bolts γ γ 3 γ 3,ser γ 4 γ 5 γ 6,ser γ 7 Note: The partial factors γ i for crane supporting structures may be defined in the National Annex. The following numerical values are recommended: γ 0 = 1,00 γ 1 = 1,00 γ = 1,5 γ 3 = 1,5 γ 3,ser = 1,10 γ 4 = 1,00 γ 5 = 1,00 γ 6,ser = 1,00 γ 7 = 1,10 The recommended values for partial safety factors γ i, will be used Lateral-torsional buckling Assessment methods (1) The lateral-torsional buckling resistance of a simply supported runway beam may be verified by checking the compression flange plus one fifth of the web against flexural buckling as a compression member. It should be checked for an axial compressive force equal to the bending moment due to the vertical actions, divided by the depth between the centroids of the flanges. The bending moment due to the lateral horizontal actions should also be taken into account, together with the effects of torsion. Note: The National Annex may specify alternative assessment methods. The method given in Annex A is recommended. The ussage of the alternative method exposed in annex A is recommended, taking into consideration the changes indicated in the corrigendum SR EN :007/AC:010 (see the conditions of application of the National Annex SR EN :007/NA:011 in Romania). Taking into account these changes the relation (A.1) becomes:

6 SR EN :007/NA:01 χ LT where: C mz k w = k zw = k α = y,ed y,rk γ 1 + C mz z,rk z,ed γ 1 + k w k B zw Rk kα B γ 1 Ed 1 (A.1) is the equivalent uniform moment factor for bending about the z-z axis, according to EN Table B.3; 0, , B BRk γ z,rk Ed z,ed γ Ed y, y,cr y,ed and z,ed are the design values of the maximum moments about the y-y and z-z axis respectively; y,rk and z,rk are the characteristic values of the resistance moment of the cross-section about its y-y and z-z axis respectively, from EN Table 6.7; y,cr B Ed is the elastic critical lateral-torsional buckling moment about the y-y axis; is the design value of the bimoment, which produces the direct longitudinal stresses σ W, Ed ; B Rk χ LT is the characteristic value of the bimoment, which can be determined as follows: taking into account σ B ω Rk W,Ed = and considering IW characteristic value of the bimoment will be obtained: I B Rk f y σ W,Ed = the γ 0 I f W y ω γ = ; where: W is the warping constant of the runway girder cross-section; ωis the warping coordinate of the point on the cross-section where the direct warping stress σ W, Ed is calculated (the corner of the compressed flange of the runway girder cross-section); is the reduction factor for lateral-torsional buckling according to 6.3. of EN The reduction factor χ LT may be determined from of EN for rolled or equivalent welded sections with equal flanges, or with unequal flanges, taking b as the width of the compression flange, provided that: I z,t /I z,c 0, ; where: I z,c and I z,t are the second moments of area about the z-z axis for the compression and tension flanges respectively. 0 Specifications concerning the ussage of relation (A.1) for the check against lateral-torsional buckling of runway girders: In case of runway girders with box cross-sections the third term of relation (A.1) can be neglected. If a surge girder is fixed along the compressed flange of the runway girder cross-section, the third term of relation (A.1) can be neglected. If the elements of the crane supporting structure are forming an element with a closed hollow crosssection, the third term of relation (A.1) can be omitted.

7 7 Serviceability limit states SR EN :007/NA: Limits for deformations and displacements (1) The specific limits, together with the serviceability load combinations under which they apply, should be agreed for each project with the crane supplier and the client. Note: The National Annex may specify the limits for vertical and horizontal deflections. The limits given in table 7.1 are recommended for horizontal deflections under the characteristic combination of actions. The limits given in table 7. are recommended for vertical deflections under the characteristic combination of actions without any dynamic amplification factors. The recommended values for the horizontal deflections indicated in table 7.1 will be adopted. Table 7.1: Limiting values of horizontal deflections Description of deflection (deformation or displacement) a) Horizontal deformation δ y of a runway beam, measured at the level of the top of the crane rail: δ y L/600 Diagram b) Horizontal displacement δ y of a frame (or of a column) at crane support level, due to crane loads: δ y h c /400 where: h c is the height to the level at which the crane is supported (on a rail or on a flange) c) Difference δ y between the horizontal displacements of adjacent frames (or columns) supporting the beams of an indoor crane runway: δ y L/600 d) Difference δ y between the horizontal displacements of adjacent columns (or frames) supporting the beams of an outdoor crane runway: - due to the combination of lateral crane forces and the inservice wind load: δ y L/600 - due to the out-of-service wind load δ y L/400 e) Change of spacing s between the centres of crane rails, including the effects of thermal changes: s 10 mm [see Note]

8 Note: SR EN :007/NA:01 Horizontal deflections and deviations of crane runways are considered together in crane design. Acceptable deflections and tolerances depend on the details and clearances in the guidance means. Provided that the clearance c between the crane wheel flanges and the crane rail (or between the alternative guidance means and the crane beam) is also sufficient to accommodate the necessary tolerances, larger deflection limits can be specified for each project if agreed with the crane supplier and the client. The recommended values for the vertical deflections indicated in table 7. will be adopted, taking into consideration the following completing remarks at point a): The vertical deformation δ z of a runway beam produced by traveling cranes with a hoist load smaller or equal than 50tf has to satisfy the following conditions: δ z L/600 and δ z 5 mm; The vertical deformation δ z of a runway beam produced by traveling cranes with a hoist load greater than 50tf has to satisfy the following conditions: δ z L/750 and δ z 5 mm. Table 7.: Limiting values of vertical deflections Description of deflection (deformation or displacement) a) Vertical deformation δ z of a runway beam: δ z L/600 and δ z 5 mm The vertical deformation δz should be taken as the total deformation due to vertical loads, less the possible precamber, as for δmax in figure A1.1 of EN b) Difference h c between the vertical deformations of two beams forming a crane runway: h c s/600 Diagram c) Vertical deformation δ pay of a runway beam for a monorail hoist block, relative to its supports, due to the payload only: δ pay L/ Reversible behaviour (1) To ensure reversible behaviour, the stresses σ Ed,ser and τ Ed,ser resulting from the relevant characteristic load combination or test load combination, calculated making due allowance where relevant for the effects of shear lag in wide flanges and for the secondary effects induced by deformations (for instance secondary moments in trusses) should be limited as follows: σ f / γ (7.a) τ Ed, ser Ed,ser y,ser f y (7.b) 3γ,ser ( σ ) + ( τ ) f x,ed,ser Ed,ser y γ, ser ( σ ) + ( σ ) ( σ x,ed,ser )( σ y,ed,ser ) + ( τ ) f x,ed,ser y,ed,ser Ed,ser y γ, ser ( σ ) + ( σ ) ( σ x,ed,ser )( σ z,ed,ser ) + ( τ ) f y γ, ser x,ed,ser 3 (7.c) z,ed,ser 3 (7.d) 3 (7.e) Ed,ser where: σ x,ed,ser is the direct stress in the longitudinal direction;

9 SR EN :007/NA:01 σ y,ed,ser is the direct stress in the lateral direction; σ z,ed,ser is the direct stress in the transverse direction; τ Ed,ser is the co-existing shear stress. Note: The numerical value for γ,ser may be defined in the National Annex. The recommended value is 1,00 generally, but 1,10 for the bottom flange of a runway beam with a monorail hoist block or an underslung crane. The recommended values for factor γ,ser will be used. 8 Fasteners, welds, surge connectors and rails 8. Welded connections (4) For high fatigue crane classes, transverse web stiffeners should not be welded to the top flanges of runway beams Note: The National Annex may specify the crane classes to be treated as high fatigue. Classes S7 to S9 according to Annex B of EN are recommended. The recommendations concerning the classification of traveling cranes in high fatigue classes will be adopted. In order to avoid unfavorable fatigue behavior, transverse web stiffeners or other attachments will not be welded directly to the tensioned flanges of runway beams. 9 Fatigue assessment 9.1 Requirement for fatigue assessment () Fatigue assessment need not be carried out for crane supporting structures if the number of cycles at more than 50% of full payload does not exceed C 0. Note: The numerical value for C 0 may be defined in the National Annex. The recommended value is The recommended values for the number of cycles, C 0,will be used. 9. Partial factors for fatigue (1) The partial factor for fatigue loads should be taken as γ Ff. Note: The numerical value for γ Ff may be defined in the National Annex. The recommended value is 1,0. The recommended values for factor γ Ff will be used. () The partial factor for fatigue resistance should be taken as γ f. Note: The National Annex may define the values for γ f. The use of table 3.1 in EN is recommended. The recommended values for the γ f factors from the table below will be used (ex SR EN :006).Se adoptă pentru coeficientul γ f valorile recomandate din tabelul de mai jos (extras din SR EN :006). According to the National Annex SR EN :006/NA:008 the values of the partial factors γ f for safe life are recommended.

10 SR EN :007/NA:01 Table 3.1(SR EN :006) - Recommended values for the partial factors γ f used for fatigue resistance Assessment method Low consequence Consequence of failure High consequence Damage tolerant Safe life Local stresses due to wheel loads on the top flange (1) In the web, the following local stresses due to wheel loads on the top flange should be taken into account: - compressive stresses σ z,ed as specified in 5.7.1, - shear stresses τ xz,ed as specified in 5.7., - unless specified otherwise, bending stresses σ T,Ed due to the lateral eccentricity e y of vertical loads F z,ed as specified in Note: The National Annex may define crane classes for which the bending stresses σ T,Ed can be neglected. Crane classes S 0 to S 3 are recommended. No additional provisions are available ultiple crane actions (5) In the absence of better information, the equivalent constant amplitude stress range σ E due to two or more cranes occasionally acting together may be obtained by applying damage equivalence factors λ dup. Note: The National Annex may define the values of the factors λ dup. It is recommended to take a value of λ dup equal to the values λ i from table.1 of EN for a loading class S i as follows: - for cranes: classes below the loading class of the crane with the lower loading class; - for 3 or more cranes:3 classes below the loading class of the crane with the lowest loading class. No additional provisions are available.

11 SR EN :007/NA:01 II. Conditions of application of the SR EN :007 Annexes and corrigendum SR EN :010 / AC: 010 Annex A [informative] Alternative assessment method for lateral-torsional buckling Annex A remains informative for the purpose of SR EN :007, corrigendum SR EN :007 / AC: 010 and the National Annex. Romanian standards contain provisions necessary for contracting. The provisions are not controlling. Users are responsible for completing the standards and their correct application. It is important that users of Romanian standards ensure they are in possession of the latest edition and all changes in force. Information on Romanian standards are published in the "Catalogue of Romanian standards" and "Bulletin of standardization" being found in the application of information and documentation "InfoStandard" in electronic format, which is updated weekly.

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