Columns Avn
1 P The columns shall be verified in compression considering the most unfavourable combination of the axial force and bending moments. In the checks, Ed, MEd, VEd should be computed as NEd NEd, G 1,1Y ov QNEd MEd MEd,G 1,1Y ov Ed Ed,G 1,1Y ov Ed,E NEd,G MEd,G, VEd,G are the compression force respectively the bending moment and shear force in the column due to the non-seismic actions included in the combination of actions for the seismic design situation NEd,E MEd,E, VEd,E are the compression...
Columns 1
1 P In primary seismic columns the design values of shear forces shall be determined in accordance with the capacity design rule, on the basis of the equilibrium of the column under end moments Mi d with ' 1,2 denoting the end sections of the column , corresponding to plastic hinge formation for positive and negative directions of seismic loading. The plastic hinges should be taken to form at the ends of the beams connected to the joints into which the column end frames, or if they form there...
Structural types and behaviour factors Structural types 1
1 P Composite steel-concrete structures shall be assigned to one of the following structural types according to the behaviour of their primary resisting structure under seismic actions a Composite moment resisting frames are those with the same definition and limitations as in 6.3.1 1 a, but in which beams and columns may be either structural steel or composite steel-concrete see Figure 6.1 b Composite concentrically braced frames are those with the same definition and limitations as in 6.3.1...
Vertical component of the seismic action
1 If avg is greater than 0,25 g 2,5 m s2 the vertical component of the seismic action, as defined in 3.2.2.3, should be taken into account in the cases listed below - for horizontal or nearly horizontal structural members spanning 20 m or more - for horizontal or nearly horizontal cantilever components longer than 5 m - for horizontal or nearly horizontal pre-stressed components - for beams supporting columns 2 The analysis for determining the effects of the vertical component of the seismic...
isolator units
elements constituting the isolation system. The devices considered in this section consist of laminated elastomeric bearings, elasto-plastic devices, viscous or friction dampers, pendulums, and other devices the behaviour of which conforms to 10.1 2 . Each unit provides a single or a combination of the following functions - vertical-load carrying capability combined with increased lateral flexibility and high vertical rigidity - energy dissipation, either hysteretic or viscous - lateral...
C No faade steel beam concrete cantilever edge strip present Figure Cc
1 When there is a concrete cantilever edge strip but no fa ade steel beam, EN 1994-1-1 2004 applies for the calculation of the moment capacity of the joint. b no concrete cantilever edge strip - no fa ade steel beam - see C.3.1.1. c concrete cantilever edge strip - no fa ade steel beam - see C.3.1.2. d no concrete cantilever edge strip - fa ade steel beam - see C.3.1.3. e concrete cantilever edge strip - fa ade steel beam - see C.3.1.4. A main beam B slab C exterior column D fa ade steel beam...
Minimum strength of masonry units
1 Except in cases of low seismicity, the normalised compressive strength of masonry units, derived in accordance with EN 772-1, should be not less than the minimum values as follows - normal to the bed face Amin - parallel to the bed face in the plane of the wall bh,min- NOTE The values ascribed to f,min and f,,mm for use in a country may be found in its National Annex of this document. The recommended values are f,,mm 5 N mm2 fbh,min 2 N mm2.
Types of construction and behaviour factors
1 Depending on the masonry type used for the seismic resistant elements, masonry buildings should be assigned to one of the following types of construction a unreinforced masonry construction b confined masonry construction c reinforced masonry construction NOTE 1 Construction with masonry systems which provide an enhanced ductility of the structure is also included see Note 2 to Table 9.1 . NOTE 2 Frames with infill masonry are not covered in this section. 2 Due to its low tensile strength...
Specific criteria Bpo
1 P The provisions in this subclause apply to composite structural systems belonging in one of the three types defined in 7.3.1e. 2 P Structural system types 1 and 2 shall be designed to behave as shear walls and dissipate energy in the vertical steel sections and in the vertical reinforcement. The infills shall be tied to the boundary elements to prevent separation. 3 P In structural system type 1, the storey shear forces shall be carried by horizontal shear in the wall and in the interface...
Local ductility condition
1 P For the required overall ductility of the structure to be achieved, the potential regions for plastic hinge formation, to be defined later for each type of building element, shall possess high plastic rotational capacities. 2 Paragraph 1 P is deemed to be satisfied if the following conditions are met a a sufficient curvature ductility is provided in all critical regions of primary seismic elements, including column ends depending on the potential for plastic hinge formation in columns see...
Eurocode Design of structures for earthquake resistance Part General rules
Eurocode 8 Calcul des structures pour leur r sistance aux Eurocode 8 Auslegung von Bauwerken gegen Erdbeben - s ismes - Partie 1 R gles g n rales, actions sismiques et Teil 1 Grundlagen, Erdbebeneinwirkungen und Regeln f r r gles pour les b timents Hochbauten This draft European Standard is submitted to CEN members for formal vote. It has been drawn up by the Technical Committee CEN TC 250. If this draft becomes a European Standard, CEN members are bound to comply with the CEN CENELEC Internal...
P
are as defined in 3.2.2.2 is the design spectrum is the behaviour factor is the lower bound factor for the horizontal design spectrum. NOTE The value to be ascribed to P for use in a country can be found in its National Annex. The recommended value for P is 0,2. 5 For the vertical component of the seismic action the design spectrum is given by expressions 3.13 to 3.16 , with the design ground acceleration in the vertical direction, avg replacing ag, S taken as being equal to 1,0 and the other...
Combination of the effects of the components of the seismic action Horizontal
1 P In general the horizontal components of the seismic action see 3.2.2.1 3 shall be taken as acting simultaneously. 2 The combination of the horizontal components of the seismic action may be accounted for as follows. a The structural response to each component shall be evaluated separately, using the combination rules for modal responses given in 4.3.3.3.2. b The maximum value of each action effect on the structure due to the two horizontal components of the seismic action may then be...
Detailing rules for coupling beams of ductility class DCM
1 P Coupling beams shall have an embedment length into the reinforced concrete wall sufficient to resist the most adverse combination of moment and shear generated by the bending and shear strength of the coupling beam. The embedment length le shall be taken to begin inside the first layer of the confining reinforcement in the wall boundary member see Figure 7.10 . The embedment length le shall be not less than 1,5 times the height of the coupling beam 2 P The design of beam wall connections...
B Transformation to an equivalent Single Degree of Freedom SDOF system
The mass of an equivalent SDOF system m is determined as and the transformation factor is given by The force F and displacement d of the equivalent SDOF system are computed as where Fb and dn are, respectively, the base shear force and the control node displacement of the Multi Degree of Freedom MDOF system.
Concrete foundation elements Scope
1 P The following paragraphs apply for the design of concrete foundation elements, such as footings, tie-beams, foundation beams, foundation slabs, foundation walls, pile caps and piles, as well as for connections between such elements, or between them and vertical concrete elements. The design of these elements shall follow the rules of EN 1998-5 2004, 5.4. 2 P If design action effects for the design of foundation elements of dissipative structures are derived on the basis of capacity design...
Structural types and behaviour factors Structural types
1 P Concrete buildings shall be classified into one of the following structural types see 5.1.2 according to their behaviour under horizontal seismic actions b dual system frame or wall equivalent c ductile wall system coupled or uncoupled d system of large lightly reinforced walls f torsionally flexible system. 2 Except for those classified as torsionally flexible systems, concrete buildings may be classified to one type of structural system in one horizontal direction and to another in the...
Detailing for local ductility
1 P The regions of a primary seismic beam up to a distance lcr hw where hw denotes the depth of the beam from an end cross-section where the beam frames into a beam-column joint, as well as from both sides of any other cross-section liable to yield in the seismic design situation, shall be considered as being critical regions. 2 In primary seismic beams supporting discontinued cut-off vertical elements, the regions up to a distance of 2hw on each side of the supported vertical element should...
Diagonal tension failure of the web due to shear
1 P The calculation of web reinforcement for the ULS verification in shear shall take into account the value of the shear ratio as MEd VEd lw . The maximum value of as in a storey should be used for the ULS verification of the storey in shear. 2 If the ratio as gt 2,0, the provisions of in EN 1992-1-1 2004 6.2.3 1 - 7 apply, with the values of z and tan9 taken as in 5.5.3.4.2 1 a . 3 If as lt 2,0 the following provisions apply a the horizontal web bars should satisfy the following expression...
Info Fcw
where hi and vi denote the thickness in metres and shear-wave velocity at a shear strain level of 10-5 or less of the i-th formation or layer, in a total of N, existing in the top 30 m. 4 P For sites with ground conditions matching either one of the two special ground types S1 or S2, special studies for the definition of the seismic action are required. For these types, and particularly for S2, the possibility of soil failure under the seismic action shall be taken into account. NOTE Special...
Specific additional measures
1 P Due to the random nature of the seismic action and the uncertainties of the post-elastic cyclic behaviour of concrete structures, the overall uncertainty is substantially higher than with non-seismic actions. Therefore, measures shall be taken to reduce uncertainties related to the structural configuration, to the analysis, to the resistance and to the ductility. 2 P Important resistance uncertainties may be produced by geometric errors. To minimize this type of uncertainty, the following...
Design and detailing rules for frames with eccentric bracings Design criteria
1 P Frames with eccentric bracings shall be designed so that specific elements or parts of elements called seismic links are able to dissipate energy by the formation of plastic bending and or plastic shear mechanisms. 2 P The structural system shall be designed so that a homogeneous dissipative behaviour of the whole set of seismic links is realised. NOTE The rules given hereafter are intended to ensure that yielding, including strain hardening effects in the plastic hinges or shear panels,...
Sliding shear failure
1 P At potential sliding shear planes for example, at construction joints within critical regions the following condition shall be satisfied where VRd,S is the design value of the shear resistance against sliding. 2 The value of VRd, S may be as follows V i f-l Asj-fyd NEd - Z MEdl z 543 Vdd is the dowel resistance of the vertical bars Vid is the shear resistance of inclined bars at an angle 9 to the potential sliding plane, e.g. construction joint is the concrete-to-concrete friction...
Moment Resisting Frames Combined With Concentric Bracings Or Infills
6.10.1 Structures with concrete cores or concrete 6.10.2 Moment resisting frames combined with concentric 6.10.3 Moment resisting frames combined with 6.11 Control of design and 7 SPECIFIC RULES FOR COMPOSITE STEEL - CONCRETE BUILDINGS 147 7.1.2 Design 7.1.3 Safety 7.2.2 Reinforcing 7.2.3 Structural 7.3 Structural types and behaviour 7.3.1 Structural 7.3.2 Behaviour 7.4 Structural 7.4.2 Stiffness of 7.5 Design criteria and detailing rules for dissipative structural behaviour common
Iv
Buildings whose integrity during earthquakes is of vital importance for civil protection, e.g. hospitals, fire stations, power plants, etc. NOTE Importance classes I, II and III or IV correspond roughly to consequences classes CC1, CC2 and CC3, respectively, defined in EN 1990 2002, Annex B. NOTE Importance classes I, II and III or IV correspond roughly to consequences classes CC1, CC2 and CC3, respectively, defined in EN 1990 2002, Annex B. 5 P The value of yI for importance class II shall be,...
Coupling elements of coupled walls
1 P Coupling of walls by means of slabs shall not be taken into account, as it is not effective. 2 The provisions of 5.5.3.1 may only be applied to coupling beams, if either one of the following conditions is fulfilled a Cracking in both diagonal directions is unlikely. An acceptable application rule is b A prevailing flexural mode of failure is ensured. An acceptable application rule is l h gt 3. 3 If neither of the conditions in 2 is met, the resistance to seismic actions should be provided...
Behaviour factors
1 Upper limit values of the behaviour factor qa for non-structural elements are given in Table 4.4. Table 4.4 Values of qa for non-structural elements Table 4.4 Values of qa for non-structural elements Cantilevering parapets or ornamentations Signs and billboards Chimneys, masts and tanks on legs acting as unbraced cantilevers along more than one half of their total height Exterior and interior walls Partitions and facades Chimneys, masts and tanks on legs acting as unbraced cantilevers along...
Bending and shear resistance
1 P Flexural and shear resistances shall be computed in accordance with EN 1992-11 2004, unless specified otherwise in the following paragraphs, using the value of the axial force resulting from the analysis in the seismic design situation. 2 In primary seismic walls the value of the normalised axial load vd should not exceed 0,4. 3 P Vertical web reinforcement shall be taken into account in the calculation of the flexural resistance of wall sections. 4 Composite wall sections consisting of...
Behaviour factors for horizontal seismic actions
1 P The upper limit value of the behaviour factor q, introduced in 3.2.2.5 3 to account for energy dissipation capacity, shall be derived for each design direction as follows qo is the basic value of the behaviour factor, dependent on the type of the structural system and on its regularity in elevation see 2 of this subclause kw is the factor reflecting the prevailing failure mode in structural systems with walls see 11 P of this subclause . 2 For buildings that are regular in elevation in...
Verification
1 P The non-structural elements, as well as their connections and attachments or anchorages, shall be verified for the seismic design situation see 3.2.4 . NOTE The local transmission of actions to the structure by the fastening of non-structural elements and their influence on the structural behaviour should be taken into account. The requirements for fastenings to concrete are given in EN1992-1-1 2004, 2.7. 2 The effects of the seismic action may be determined by applying to the...
Energy dissipation capacity and ductility classes
1 P The design of earthquake resistant concrete buildings shall provide the structure with an adequate capacity to dissipate energy without substantial reduction of its overall resistance against horizontal and vertical loading. To this end, the requirements and criteria of Section 2 apply. In the seismic design situation adequate resistance of all structural elements shall be provided, and non-linear deformation demands in critical regions should be commensurate with the overall ductility...
Design Of Buildings
1 P Section 4 contains general rules for the earthquake-resistant design of buildings and shall be used in conjunction with Sections 2, 3 and 5 to 9. 2 Sections 5 to 9 are concerned with specific rules for various materials and elements used in buildings. 3 Guidance on base-isolated buildings is given in Section 10. 4.2 Characteristics of earthquake resistant buildings 4.2.1 Basic principles of conceptual design 1 P In seismic regions the aspect of seismic hazard shall be taken into account in...
Base Isolation
10.3 Fundamental 10.4 Compliance 10.5 General design 10.5.1 General provisions concerning the 10.5.2 Control of undesirable 10.5.3 Control of differential seismic ground 10.5.4 Control of displacements relative to surrounding ground and constructions 192 10.5.5 Conceptual design of base isolated 10.6 Seismic 10.7 Behaviour 10.8 Properties of the isolation 10.9 Structural 10.9.2 Equivalent linear 10.9.3 Simplified linear 10.9.4 Modal simplified linear 10.9.5 Time-history 10.9.6 Non structural...
torsionally flexible system
dual or wall system not having a minimum torsional rigidity see 5.2.2.1 4 P and 6 NOTE 1 An example of this is a structural system consisting of flexible frames combined with walls concentrated near the centre of the building in plan. NOTE 2 This definition does not cover systems containing several extensively perforated walls around vertical services and facilities. For such systems the most appropriate definition of the respective overall structural configuration should be chosen on a...