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...

A

Figure 7.1 Composite structural systems. Composite walls a) Type 1 - steel or composite moment frame with connected concrete infill panels b) Type 2 -composite walls reinforced by connected encased vertical steel sections. Figure 7.2 Composite structural systems. Type 3 - composite or concrete walls coupled by steel or composite beams. (2) In all types of composite structural systems the energy dissipation takes place in the vertical steel sections and in the vertical reinforcements of the...

Additional measures for masonry infilled frames General

(1)P 4.3.6.1 to 4.3.6.3 apply to frame or frame equivalent dual concrete systems of DCH (see Section 5) and to steel or steel-concrete composite moment resisting frames of DCH (see Sections 6 and 7) with interacting non-engineered masonry infills that fulfil all of the following conditions a) they are constructed after the hardening of the concrete frames or the assembly of the steel frame b) they are in contact with the frame (i.e. without special separation joints), but without structural...

Additional requirements for confined masonry

(1)P The horizontal and vertical confining elements shall be bonded together and anchored to the elements of the main structural system. (2)P In order to obtain an effective bond between the confining elements and the masonry, the concrete of the confining elements shall be cast after the masonry has been built. (3) The cross-sectional dimensions of both horizontal and vertical confining elements may not be less than 150 mm. In double-leaf walls the thickness of confining elements should assure...

Additional requirements for unreinforced masonry satisfying EN

(1) Horizontal concrete beams or, alternatively, steel ties should be placed in the plane of the wall at every floor level and in any case with a vertical spacing not more than 4 m. These beams or ties should form continuous bounding elements physically connected to each other . NOTE Beams or ties continuous over the entire periphery are essential. (2) The horizontal concrete beams should have longitudinal reinforcement with a cross-sectional area of not less than 200 mm2.

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...

Beamcolumn joints

(1)P The horizontal shear acting around the core of a joint between primary seismic beams and columns shall be determined taking into account the most adverse conditions under seismic loading, i.e. capacity design conditions for the beams framing into the joint and the lowest compatible values of shear forces in the framing elements. (2) Simplified expressions for the horizontal shear force acting on the concrete core of the joints may be used as follows As1 is the area of the beam top...

Beams

(1)P In primary seismic beams the design shear forces shall be determined in accordance with the capacity design rule, on the basis of the equilibrium of the beam under a) the transverse load acting on it in the seismic design situation and b) end moments Mi d (with i 1,2 denoting the end sections of the beam), 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 or (if they form...

Faade steel beam present slab extending up to column outside face no concrete cantilever edge strip Figure Cd

(1) When there is a fa ade steel beam but no concrete cantilever edge strip, the moment capacity of the joint may include the contribution of the slab reinforcements provided that the requirements in (2) to (7) of this subclause are satisfied. (2) Reinforcing bars of the slab should be effectively anchored to the shear connectors of the fa ade steel beam. (3) The fa ade steel beam should be fixed to the column. (4)P The cross-sectional area of reinforcing steel As shall be such that yielding of...

No faade steel beam slab extending up to column outside face or beyond as a concrete cantilever edge strip Figure Ccde

(1) When no fa ade steel beam is present, the moment capacity of the joint may be calculated from the compressive force developed by the combination of the following two mechanisms mechanism 1 direct compression on the column. The design value of the force that is transferred by means of this mechanism should not exceed the value given by the following expression mechanism 2 compressed concrete struts inclined to the column sides. If the angle of inclination is equal to 45 , the design value of...

No faade steel beam slab extending up to the column inside face Figure

(1) When the concrete slab is limited to the interior face of the column, the moment capacity of the joint may be calculated on the basis of the transfer of forces by direct compression (bearing) of the concrete on the column flange. This capacity may be calculated from the compressive force computed in accordance with (2) of this subclause, provided that the confining reinforcement in the slab satisfies (4) of this subclause. (2) The maximum value of the force transmitted to the slab may be...

No transverse beam present Figure

(1) When no transverse beam is present, the moment capacity of the joint may be calculated from the compressive force developed by the combination of the following two mechanisms mechanism 1 direct compression on the column. The design value of the force that is transferred by means of this mechanism should not exceed the value given by the following expression mechanism 2 compressed concrete struts inclined at 45 to the column sides. The design value of the force that is transferred by means...

Condition for disregarding the composite character of beams with slab

(1)P The plastic resistance of a beam section composite with slab (lower or upper bound plastic resistance of dissipative zones) may be computed taking into account only the steel section (design in accordance with concept c) as defined in 7.1.2) if the slab is totally disconnected from the steel frame in a circular zone around a column of diameter 2beff, with beff being the larger of the effective widths of the beams connected to that column. (2) For the purposes of (1)P, totally disconnected...

Connections located away from critical regions

(1) Connections of precast elements considered to be away from critical regions should be located at a distance from the end face of the closest critical region, at least equal to the largest of the cross-section dimensions of the element where this critical region lies. (2) Connections of this type should be dimensioned for a) a shear force determined from the capacity design rule of 5.4.2.2 and 5.4.2.3 with a factor to account for overstrength due to strain-hardening of steel, yRd, equal to...

Connections of vertical elements with foundation beams or walls

(1)P The common (joint) region of a foundation beam or foundation wall and a vertical element shall follow the rules of 5.4.3.3 or 5.5.3.3 as a beam-column joint region. (2) If a foundation beam or foundation wall of a DCH structure is designed for action effects derived on the basis of capacity design considerations in accordance with 4.4.2.6(2)P, the horizontal shear force Vjhd in the joint region is derived on the basis of analysis results in accordance with 4.4.2.6(2)P, (4), (5), and (6)....

Control of design and construction

(1)P The control of design and construction shall ensure that the real structure corresponds to the designed structure. (2) To this end, in addition to the provisions of EN 1993, the following requirements should be met a) the drawings made for fabrication and erection should indicate the details of connections, sizes and qualities of bolts and welds as well as the steel grades of the members, noting the maximum permissible yield stress fy,max of the steel to be used by the fabricator in the...

Control of differential seismic ground motions

(1) The structural elements located above and below the isolation interface should be sufficiently rigid in both horizontal and vertical directions, so that the effects of differential seismic ground displacements are minimised. This does not apply to bridges or elevated structures, where the piles and piers located under the isolation interface may be deformable. (2) In buildings, (1) is considered satisfied if all the conditions stated below are satisfied a) A rigid diaphragm is provided...

Control of undesirable movements

(1) To minimise torsional effects, the effective stiffness centre and the centre of damping of the isolation system should be as close as possible to the projection of the centre of mass on the isolation interface. (2) To minimise different behaviour of isolating devices, the compressive stress induced in them by the permanent actions should be as uniform as possible. (3)P Devices shall be fixed to the superstructure and the substructure. (4)P The isolation system shall be designed so that...

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...

Design criteria for dissipative structures

(1)P Structures with dissipative zones shall be designed such that yielding or local buckling or other phenomena due to hysteretic behaviour do not affect the overall stability of the structure. NOTE The q factors given in Table 6.2 are deemed to conform to this requirement (see 2.2.2(2)). (2)P Dissipative zones shall have adequate ductility and resistance. The resistance shall be verified in accordance with EN 1993. (3) Dissipative zones may be located in the structural members or in the...

Design rules for connections in dissipative zones

(1)P The design of connections shall be such as to limit localization of plastic strains, high residual stresses and prevent fabrication defects. (2) Non dissipative connections of dissipative members made by means of full penetration butt welds may be deemed to satisfy the overstrength criterion. (3) For fillet weld or bolted non dissipative connections, the following expression should be satisfied Rd is the resistance of the connection in accordance with EN 1993 Rfy is the plastic resistance...

Design rules for inverted pendulum structures

(1) In inverted pendulum structures (defined in 6.3.1(d)), the columns should be verified in compression considering the most unfavourable combination of the axial force and bending moments. (2) In the checks, NEd, MEd, VEd should be computed as in 6.6.3. (3) The non-dimensional slenderness of the columns should be limited to X< 1,5. (4) The interstorey drift sensitivity coefficient 9 as defined in 4.4.2.2 should be limited to 9 < 0,20.

Detailing for local ductility

(1) Vertical bars necessary for the verification of the ULS in bending with axial force, or for the satisfaction of any minimum reinforcement provisions, should be engaged by a hoop or a cross-tie with a diameter of not less than 6 mm or one third of the vertical bar diameter, dbL. Hoops and cross-ties should be at a vertical spacing of not more than 100 mm or 8dbL, whichever is less. (2) Vertical bars necessary for the verification of the ULS in bending with axial force and laterally...

Detailing rules

Fyd is the design yield strength of the plate and pl is the horizontal area of the plate. (2)P The connections between the plate and the boundary members (columns and beams), as well as the connections between the plate and the concrete encasement, shall be designed such that full yield strength of the plate can be developed. (3)P The steel plate shall be continuously connected on all edges to structural steel framing and boundary members with welds and or bolts to develop the yield strength of...

Detailing rules for connections

(1)P Compression members and their connections (e.g. carpenter joints), which may fail due to deformations caused by load reversals, shall be designed in such a way that they are prevented from separating and remain in their original position. (2)P Bolts and dowels shall be tightened and tight fitted in the holes. Large bolts and dowels (d > 16 mm) shall not be used in timber-to-timber and steel-to-timber connections, except in combination with timber connectors. (3) Dowels, smooth nails and...

Detailing rules for horizontal diaphragms

(1)P For horizontal diaphragms under seismic actions EN 1995-1-1 2004 applies with the following modifications a) the increasing factor 1,2 for resistance of fasteners at sheet edges shall not be used b) when the sheets are staggered, the increasing factor of 1,5 for the nail spacing along the discontinuous panel edges shall not be used c) the distribution of the shear forces in the diaphragms shall be evaluated by taking into account the in-plan position of the lateral load resisting vertical...

Ductile Walls

(1)P The provisions cover single primary seismic walls, as well as individual components of coupled primary seismic walls, under in-plane action effects, with full embedment and anchorage at their base in adequate basements and foundations, so that the wall is not allowed to rock. In this respect, walls supported by slabs or beams are not permitted (see also 5.4.1.2.5). (2) Paragraph 5.4.1.2.3(1) applies. (3) Additional requirements apply with respect to the thickness of the confined boundary...

Equivalent linear analysis

(1) Subject to the conditions in (5) of this subclause, the isolation system may be modelled with equivalent linear visco-elastic behaviour, if it consists of devices such as laminated elastomeric bearings, or with bilinear hysteretic behaviour if the system consists of elasto-plastic types of devices. (2) If an equivalent linear model is used, the effective stiffness of each isolator unit (i.e. the secant value of the stiffness at the total design displacement ddb) should be used, while...

Evaluation of the resistance of connections

(1) The design resistance of the connections between precast concrete elements should be calculated in accordance with the provisions of EN 1992-1-1 2004, 6.2.5 and of EN 1992-1-1 2004, Section 10, using the material partial factors of 5.2.4(2) and (3). If those provisions do not adequately cover the connection under consideration, its resistance should be evaluated by means of appropriate experimental studies. (2) In evaluating the resistance of a connection against sliding shear, friction...

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...

Filled Composite Columns

(1) The relationship between the ductility class of the structure and the allowable slenderness d t or h t is given in Table 7.3. (2) The shear resistance of dissipative columns should be determined on the basis of the structural steel section or on the basis of the reinforced concrete section with the steel hollow section taken only as shear reinforcement. (3) In non-dissipative members, the shear resistance of the column should be determined in accordance with EN 1994-1-1.

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.

Geometrical constraints Beams

(1)P The eccentricity of the beam axis shall be limited relative to that of the column into which it frames to enable efficient transfer of cyclic moments from a primary seismic beam to a column to be achieved. (2) To enable the requirement specified in (1)P to be met the distance between the centroidal axes of the two members should be limited to less than bc 4, where bc is the largest cross-sectional dimension of the column normal to the longitudinal axis of the beam. (3)P To take advantage...

Ground Conditions And Seismic Action

(1)P Appropriate investigations shall be carried out in order to identify the ground conditions in accordance with the types given in 3.1.2. (2) Further guidance concerning ground investigation and classification is given in EN 1998-5 2004, 4.2. (3) The construction site and the nature of the supporting ground should normally be free from risks of ground rupture, slope instability and permanent settlements caused by liquefaction or densification in the event of an earthquake. The possibility of...

Irregularities due to masonry infills Irregularities in plan

(1) Strongly irregular, unsymmetrical or non-uniform arrangements of infills in plan should be avoided (taking into account the extent of openings and perforations in infill panels). (2) In the case of severe irregularities in plan due to the unsymmetrical arrangement of the infills (e.g. existence of infills mainly along two consecutive faces of the building), spatial models should be used for the analysis of the structure. Infills should be included in the model and a sensitivity analysis...

Large lightly reinforced wall

Wall with large cross-sectional dimensions, that is, a horizontal dimension lw at least equal to 4,0 m or two-thirds of the height hw of the wall, whichever is less, which is expected to develop limited cracking and inelastic behaviour under the seismic design situation NOTE Such a wall is expected to transform seismic energy to potential energy (through temporary uplift of structural masses) and to energy dissipated in the soil through rigid-body rocking, etc. Due to its dimensions, or to...

Material requirements

(1)P Concrete of a class lower than C 16 20 shall not be used in primary seismic elements. (2)P With the exceptions of closed stirrups and cross-ties, only ribbed bars shall be used as reinforcing steel in critical regions of primary seismic elements. (3)P In critical regions of primary seismic elements reinforcing steel of class B or C in EN 1992-1-1 2004, Table C.1 shall be used. (4)P Welded wire meshes may be used, if they meet the requirements in (2)P and (3)P of this subclause.

Materials

(1)P Structural steel shall conform to standards referred to in EN 1993. (2)P The distribution of material properties, such as yield strength and toughness, in the structure shall be such that dissipative zones form where they are intended to in the design. NOTE Dissipative zones are expected to yield before other zones leave the elastic range during the earthquake. (3) The requirement (2)P may be satisfied if the yield strength of the steel of dissipative zones and the design of the structure...

Materials and properties of dissipative zones

(1)P The relevant provisions of EN 1995 apply. With respect to the properties of steel elements, EN 1993 applies. (2)P When using the concept of dissipative structural behaviour, the following provisions apply a) only materials and mechanical fasteners providing appropriate low cycle fatigue behaviour may be used in joints regarded as dissipative zones b) glued joints shall be considered as non-dissipative zones c) carpenter joints may only be used when they can provide sufficient energy...

Members not containing seismic links

(1) The members not containing seismic links should conform to the rules in 6.8.3, taking into account the combined resistance of steel and concrete in the case of composite elements and the relevant rules for members in 7.6 and in EN 1994-1-1 2004. (2) Where a link is adjacent to a fully encased composite column, transverse reinforcement meeting the requirements of 7.6.5 should be provided above and below the link connection. (3) In case of a composite brace under tension, only the...

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...

NRdMEd VEd NEdG yov EdE

NRd (MEd,VEd) is the axial design resistance of the column or diagonal member in accordance with EN 1993, taking into account the interaction with the bending moment MEd and the shear VEd taken at their design value in the seismic situation NEd,G is the compression force in the column or diagonal member due to the non-seismic actions included in the combination of actions for the seismic design situation NEd,E is the compression force in the column or diagonal member due to the design seismic...

Overdesigned connections

(1) The design action-effects of overdesigned connections should be derived on the basis of the capacity design rules of 5.4.2.2 and 5.4.2.3, on the basis of overstrength flexural resistances at the end sections of critical regions equal to yRd.MRd, with the factor yRd taken as being equal to 1,20 for DCM and to 1,35 for DCH. (2) Terminating reinforcing bars of the overdesigned connection should be fully anchored before the end section(s) of the critical region. (3) The reinforcement of 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...

Requirements and criteria

(1)P The consequences of irregularity in plan produced by the infills shall be taken into account. (2)P The consequences of irregularity in elevation produced by the infills shall be taken into account. (3)P Account shall be taken of the high uncertainties related to the behaviour of the infills (namely, the variability of their mechanical properties and of their attachment to the surrounding frame, their possible modification during the use of the building, as well as their non-uniform degree...

Rules

(1) Depending on the product ag-S at the site and the type of construction, the allowable number of storeys above ground, n, should be limited and walls in two orthogonal directions with a minimum total cross-sectional area min, in each direction, should be provided. The minimum cross-sectional area is expressed as a minimum percentage, pA,min, of the total floor area per storey. NOTE The values ascribed to n and pA,min for use in a country may by found in its National Annex of this document....

Safety verifications

(1)P For ultimate limit state verifications the partial factors for material properties yc and ys shall take into account the possible strength degradation of the materials due to cyclic deformations. (2) If more specific data are not available, the values of the partial factors yc and ys adopted for the persistent and transient design situations should be applied, assuming that due to the local ductility provisions the ratio between the residual strength after degradation and the initial one...

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...

Secondary seismic members and resistances

(1)P A limited number of structural members may be designated as secondary seismic members in accordance with 4.2.2. (2) Rules for the design and detailing of secondary seismic elements are given in 5.7. (3) Resistances or stabilising effects not explicitly taken into account in calculations may enhance both strength and energy dissipation (e.g. membrane reactions of slabs mobilised by upward deflections of structural walls). (4) Non-structural elements may also contribute to energy...

Shear Walls Composite With Structural Steel Elements

7.10.1 Specific 7.10.3 Detailing rules for composite walls of ductility class 7.10.4 Detailing rules for coupling beams of ductility class 7.10.5 Additional detailing rules for ductility class 7.11 Design and detailing rules for composite steel plate shear walls 172 7.11.1 Specific 7.11.3 Detailing 7.12 CONTROL OF DESIGN AND 8 SPECIFIC RULES FOR TIMBER 8.1.3 Design 8.2 Materials and properties of dissipative 8.3 Ductility classes and behaviour 8.4 Structural 8.5 Detailing 8.5.2 Detailing rules...

Specific additional measures

(1) Only regular precast structures are covered by 5.11 (see 4.2.3). Nonetheless, the verification of precast elements of irregular structures may be based on the provisions of this subsection. (2) All vertical structural elements should be extended to the foundation level without a break. (3) Uncertainties related to resistances are as in 5.2.3.7(2)P. (4) Uncertainties related to ductility are as in 5.2.3.7(3)P. 5.11.1.4 Behaviour factors (1) For precast-structures observing the provisions of...

Specific criteria

(1)P Composite frames with eccentric bracings shall be designed so that the dissipative action will occur essentially through yielding in shear of the links. All other members shall remain elastic and failure of connections shall be prevented. (2)P Columns, beams and braces shall be either structural steel or composite. (3)P The braces, columns and beam segments outside the link segments shall be designed to remain elastic under the maximum forces that can be generated by the fully yielded and...

Specific Rules For Concrete Buildings

5.1.2 Terms and 5.2 Design 5.2.1 Energy dissipation capacity and ductility classes 5.2.2 Structural types and behaviour 5.2.2.1 Structural 5.2.2.2 Behaviour factors for horizontal seismic 5.2.3 Design criteria 5.2.3.2 Local resistance 5.2.3.3 Capacity design 5.2.3.4 Local ductility 5.2.3.5 Structural 5.2.3.6 Secondary seismic members and 5.2.3.7 Specific additional 5.2.4 Safety 5.3 Design to EN 5.3.3 Behaviour 5.4 Design for 5.4.1 Geometrical constraints and 5.4.1.1 Material 5.4.1.2 Geometrical...

Steel beams composite with slab

(1)P The design objective of this subclause is to maintain the integrity of the concrete slab during the seismic event, while yielding takes place in the bottom part of the steel section and or in the rebars of the slab. (2)P If it is not intended to take advantage of the composite character of the beam section for energy dissipation, 7.7.5 shall be applied. (3) Beams intended to behave as composite elements in dissipative zones of the earthquake resistant structure may be designed for full or...

Structural analysis

(1)P The structural model for the analysis of the building shall represent the stiffness properties of the entire system. (2)P The stiffness of the structural elements shall be evaluated taking into account both their flexural and shear flexibility and, if relevant, their axial flexibility. Uncracked elastic stiffness may be used for analysis or, preferably and more realistically, cracked stiffness in order to account for the influence of cracking on deformations and to better approximate 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...

Tiebeams and foundation beams

(1)P Stub columns between the top of a footing or pile cap and the soffit of tie-beams or foundation slabs shall be avoided. To this end, the soffit of tie-beams or foundation slabs shall be below the top of the footing or the pile cap. (2) Axial forces in tie-beams or tie-zones of foundation slabs in accordance with 5.4.1.2(6) and (7) of EN 1998-5, should be taken in the verification to act together with the action effects derived in accordance with 4.4.2.6(2)P or 4.4.2.6(3) for the seismic...

To All Structural Types

7.5.2 Design criteria for dissipative 7.5.3 Plastic resistance of dissipative 7.5.4 Detailing rules for composite connections in dissipative 7.6 Rules for 7.6.2 Steel beams composite with 7.6.3 Effective width of 7.6.4 Fully encased composite 7.6.5 Partially-encased 7.6.6 Filled Composite 7.7 Design and detailing rules for moment 7.7.1 Specific 7.7.3 Rules for beams and 7.7.4 Beam to column 7.7.5 Condition for disregarding the composite character of beams with slab 167 7.8 Design and detailing...

Wall system

Structural system in which both vertical and lateral loads are mainly resisted by vertical structural walls, either coupled or uncoupled, whose shear resistance at the building base exceeds 65 of the total shear resistance of the whole structural system NOTE 1 In this definition and in the ones to follow, the fraction of shear resistance may be substituted by the fraction of shear forces in the seismic design situation. NOTE 2 If most of the total shear resistance of the walls included in the...

Nonlinear timehistory analysis

(1) The time-dependent response of the structure may be obtained through direct numerical integration of its differential equations of motion, using the accelerograms defined in 3.2.3.1 to represent the ground motions. (2) The structural element models should conform to 4.3.3.4.1(2)-(4) and be supplemented with rules describing the element behaviour under post-elastic unloading-reloading cycles. These rules should realistically reflect the energy dissipation in the element over the range of...

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...

Resistance of horizontal diaphragms

(1)P Diaphragms and bracings in horizontal planes shall be able to transmit, with sufficient overstrength, the effects of the design seismic action to the lateral load-resisting systems to which they are connected. (2) The requirement in (1)P of this subclause is considered to be satisfied if for the relevant resistance verifications the seismic action effects in the diaphragm obtained from the analysis are multiplied by an overstrength factor yd greater than 1,0. NOTE The values to be ascribed...

Seismic joint condition

(1)P Buildings shall be protected from earthquake-induced pounding from adjacent structures or between structurally independent units of the same building. (2) (1)P is deemed to be satisfied (a) for buildings, or structurally independent units, that do not belong to the same property, if the distance from the property line to the potential points of impact is not less than the maximum horizontal displacement of the building at the corresponding level, calculated in accordance with expression...

Resistance of foundations

(1)P The foundation system shall conform to EN 1998-5 2004, Section 5 and to EN 1997-1 2004. (2)P The action effects for the foundation elements shall be derived on the basis of capacity design considerations accounting for the development of possible overstrength, but they need not exceed the action effects corresponding to the response of the structure under the seismic design situation inherent to the assumption of an elastic behaviour (q 1,0). (3) If the action effects for the foundation...

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...

Dch

Frame system, dual system, coupled wall system (3) For buildings which are not regular in elevation, the value of qo should be reduced by 20 (see 4.2.3.1(7) and Table 4.1). (4) a1 and au are defined as follows a1 is the value by which the horizontal seismic design action is multiplied in order to first reach the flexural resistance in any member in the structure, while all other design actions remain constant au is the value by which the horizontal seismic design action is multiplied, in order...

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...

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...

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...

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...

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...

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.

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...

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

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...

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

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...

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...

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...