Vid i fyd [cos li sin s lw

5.5.3.4.5 Detailing for local ductility (9) If the wall is connected to a flange with thickness bf > hs 15 and width lf > hs 5 (where hs denotes the clear storey height), and the confined boundary element needs to extend beyond the flange into the web for an additional length of up to 3bwo, then the thickness bw of the boundary element in the web should only follow the provisions in 5.4.1.2.3(1) for bwo (Figure 5.11). Figure 5.11 Minimum thickness of confined boundary elements in DCH walls...

And Note to apply

(7) In fully encased framed web panels of beam column connections, the panel zone resistance may be computed as the sum of contributions from the concrete and steel shear panel, if all the following conditions are satisfied a) the aspect ratio hb hc of the panel zone is Vwp,Ed is the design shear force in the web panel due to the action effects, taking into account the plastic resistance of the adjacent composite dissipative zones in beams or connections Vwp,Rd is the shear resistance of the...

Castinplace concrete piles and pile caps

(1)P The top of the pile up to a distance to the underside of the pile cap of twice the pile cross-sectional dimension, d, as well as the regions up to a distance of 2d on each side of an interface between two soil layers with markedly different shear stiffness (ratio of shear moduli greater than 6), shall be detailed as potential plastic hinge regions. To this end, they shall be provided with transverse and confinement reinforcement following the rules for column critical regions of the...

Design concepts

(1)P Earthquake resistant steel buildings shall be designed in accordance with one of the following concepts (see Table 6.1) - Concept a) Low-dissipative structural behaviour - Concept b) Dissipative structural behaviour. Table 6.1 Design concepts, structural ductility classes and upper limit reference Table 6.1 Design concepts, structural ductility classes and upper limit reference Range of the reference values of the behaviour factor Low dissipative structural behaviour also limited by the...

Detailing rules for composite connections in dissipative zones

(1)P The design shall limit localization of plastic strains and high residual stresses and prevent fabrication defects. (2)P The integrity of the concrete in compression shall be maintained during the seismic event and yielding shall be limited to the steel sections. (3) Yielding of the reinforcing bars in a slab should be allowed only if beams are designed to conform to 7.6.2(8). (4) For the design of welds and bolts, 6.5 applies. (5) The local design of the reinforcing bars needed in the...

Ductility classes and behaviour factors

(1)P Depending on their ductile behaviour and energy dissipation capacity under seismic actions, timber buildings shall be assigned to one of the three ductility classes L, M or H as given in Table 8.1, where the corresponding upper limit values of the behaviour factors are also given. NOTE Geographical limitations on the use of ductility classes M and H may be found in the relevant National Annex. Table 8.1 Design concept, Structural types and upper limit values of the behaviour factors for...

Figure Definition of elements in moment frame structures

Table 7.5 I Partial effective width be of slab for elastic analysis of the structure Table 7.5 I Partial effective width be of slab for elastic analysis of the structure For negative M 0,05 l For positive M 0,0375 l Not present, or re-bars not anchored For negative M 0 For positive M 0,025 l

Figure Design envelope of the shear forces in the walls of a dual system Special provisions for large lightly

(1)P To ensure that flexural yielding precedes attainment of the ULS in shear, the shear force FEd from the analysis shall be increased. (2) The requirement in (1)P of this subclause is considered to be satisfied if at every storey of the wall the design shear force VEd is obtained from the shear force calculated from the analysis, VEd, in accordance with the following expression (3)P The additional dynamic axial forces developed in large walls due to uplifting from the soil, or due to the...

Fully encased composite columns

(1) In dissipative structures, critical regions are present at both ends of all column clear lengths in moment frames and in the portion of columns adjacent to links in eccentrically braced frames. The lengths lcr of these critical regions (in metres) are specified by expression (5.14) for ductility class M, or by expression (5.30) for ductility class H, with hc in these expressions denoting the depth of the composite section (in metres). (2) To satisfy plastic rotation demands and to...

General provisions concerning the devices

(1)P Sufficient space between the superstructure and substructure shall be provided, together with other necessary arrangements, to allow inspection, maintenance and replacement of the devices during the lifetime of the structure. (2) If necessary, the devices should be protected from potential hazardous effects, such as fire, and chemical or biological attack. (3) Materials used in the design and construction of the devices should conform to the relevant existing norms.

Moment resisting frames combined with infills

(1)P Moment resisting frames in which reinforced concrete infills are positively connected to the steel structure shall be designed in accordance with Section 7. (2)P The moment resisting frames in which the infills are structurally disconnected from the steel frame on the lateral and top sides shall be designed as steel structures. (3) The moment resisting frames in which the infills are in contact with the steel frame, but are not positively connected to that frame, should satisfy the...

Precast largepanel walls

(1) EN 1992-1-1, Section 10 applies with the following modifications a) The total minimum vertical reinforcement ratio refers to the actual cross-sectional area of concrete and should include the vertical bars of the web and the boundary elements b) Mesh reinforcement in a single curtain is not allowed c) A minimum confinement should be provided to the concrete near the edge of all precast panels, as specified in 5.4.3.4.2 or 5.5.3.4.5 for columns, over a square section of side length bw, where...

Provisions for concrete diaphragms

(1) A solid reinforced concrete slab may be considered to serve as a diaphragm, if it has a thickness of not less than 70 mm and is reinforced in both horizontal directions with at least the minimum reinforcement specified in EN 1992-1-1 2004. (2) A cast-in-place topping on a precast floor or roof system may be considered as a diaphragm, if a) it meets the requirements of (1) of this subclause b) it is designed to provide alone the required diaphragm stiffness and resistance and c) it is cast...

Safety verifications at Ultimate Limit State

(1)P The substructure shall be verified under the inertia forces directly applied to it and the forces and moments transmitted to it by the isolation system. (2)P The Ultimate Limit State of the substructure and the superstructure shall be checked using the values of yM defined in the relevant sections of this Eurocode. (3)P In buildings, safety verifications regarding equilibrium and resistance in the substructure and in the superstructure shall be performed in accordance with 4.4. Capacity...

Simplified linear analysis

(1) The simplified linear analysis method considers two horizontal dynamic translations and superimposes static torsional effects. It assumes that the superstructure is a rigid solid translating above the isolation system, subject to the conditions of (2) and (3) of this subclause. Then the effective period of translation is M is the mass of the superstructure Keff is the effective horizontal stiffness of the isolation system as defined in 10.9.2(2). (2) The torsional movement about the...

Structural types

(1)P Steel buildings shall be assigned to one of the following structural types according to the behaviour of their primary resisting structure under seismic actions (see Figures 6.1 to 6.8). a) Moment resisting frames, are those in which the horizontal forces are mainly resisted by members acting in an essentially flexural manner. b) Frames with concentric bracings, are those in which the horizontal forces are mainly resisted by members subjected to axial forces. c) Frames with eccentric...

T eff fydT

Fyd,T is the design yield strength of the transverse reinforcement in the slab. The cross-sectional area AT of this reinforcement should be uniformly distributed over a length of the beam equal to bb. The distance of the first reinforcing bar to the column flange should not exceed 30 mm. (4) The cross-sectional area AT of steel defined in (3) may be partly or totally provided by reinforcing bars placed for other purposes, for instance for the bending resistance of the slab. (a) elevation A main...

Global and local ductility condition

(1)P It shall be verified that both the structural elements and the structure as a whole possess adequate ductility, taking into account the expected exploitation of ductility, which depends on the selected system and the behaviour factor. (2)P Specific material related requirements, as defined in Sections 5 to 9, shall be satisfied, including, when indicated, capacity design provisions in order to obtain the hierarchy of resistance of the various structural components necessary for ensuring...

Evaluation of precast structures

(1) In modelling of precast structures, the following evaluations should be made. a) Identification of the different roles of the structural elements as one of the following - those resisting only gravity loads, e.g. hinged columns around a reinforced concrete core - those resisting both gravity and seismic loads, e.g. frames or walls - those providing adequate connection between structural elements, e.g. floor or roof diaphragms. b) Ability to fulfil the seismic resistance provisions of 5.1 to...

Design and detailing of secondary seismic elements

(1)P Clause 5.7 applies to elements designated as secondary seismic elements, which are subjected to significant deformations in the seismic design situation (e.g. slab ribs are not subject to the requirements of 5.7). Such elements shall be designed and detailed to maintain their capacity to support the gravity loads present in the seismic design situation, when subjected to the maximum deformations under the seismic design situation. (2)P Maximum deformations due to the seismic design...

Beams and columns

(1) Beams and columns with axial forces should meet the following minimum resistance requirement Npl,Rd(MEd) > NEd,G + 1,1yov Q.NEd,E (6.12) Npl,Rd(MEd) is the design buckling resistance of the beam or the column in accordance with EN 1993, taking into account the interaction of the buckling resistance with the bending moment MEd, defined as its design value in the seismic design situation NEd,G is the axial force in the beam or in the column due to the non-seismic actions included in the...

Info

Magnification factor on seismic displacements for isolation devices. 1 P EN 1998 applies to the design and construction of buildings and civil engineering works in seismic regions. Its purpose is to ensure that in the event of earthquakes - structures important for civil protection remain operational. NoTE The random nature of the seismic events and the limited resources available to counter their effects are such as to make the attainment of these goals...

Columns

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 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...

Specific criteria

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...

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...

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.

Detailing for local ductility

Beam Reinforcement Detailing

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...

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,...

Coupling elements of coupled walls

Anchorage Column Lap Length

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...

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...

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...