M

Resistance of pins at serviceability limit state

7M6,ser

Preload of high strength bolts

7m7

Resistance of concrete

yc see EN 1992

NOTE: Numerical values for yM may be defined in the National Annex. Recommended values are as follows: i>M2 = 1,25 ; yM3 = 1,25 for hybrid connections or connections under fatigue loading and yM3 = 1,1 for other design situations; jui = 1,0 ; 7ms = 1,0 ; yM6,ser = 1,0 ; jui =1,1.

(3) Joints subject to fatigue should also satisfy the principles given in EN 1993-1-9.

2.3 Applied forces and moments

(1) The forces and moments applied to joints at the ultimate limit state shall be determined according to the principles in EN 1993-1-1.

2.4 Resistance of joints

(1) The resistance of a joint shall be determined on the basis of the resistances of its basic components.

(2) Linear-elastic or elastic-plastic analysis may be used in the design of joints.

(3) Where fasteners with different stiffenesses are used to carry a shear load the fasteners with the highest stiffness should be designed to carry the design load. An exception to this design method is given in 3.9.3.

2.5 Design assumptions

(1) Joints shall be designed on the basis of a realistic assumption of the distribution of internal forces and moments. The following assumptions should be used to determine the distribution of forces:

(a) the internal forces and moments assumed in the analysis are in equilibrium with the forces and moments applied to the joints,

(b) each element in the joint is capable of resisting the internal forces and moments,

(c) the deformations implied by this distribution do not exceed the deformation capacity of the fasteners or welds and the connected parts,

(d) the assumed distribution of internal forces shall be realistic with regard to relative stiffnesses within the joint,

(e) the deformations assumed in any design model based on elastic-plastic analysis are based on rigid body rotations and/or in-plane deformations which are physically possible, and

(f) any model used is in compliance with the evaluation of test results (see EN 1990).

(2) The application rules given in this part satisfy 2.5(1).

2.6 Joints loaded in shear subject to impact, vibration and/or load reversal

(1) Where a joint loaded in shear is subject to impact or significant vibration one of the following jointing methods should be used:

- welding

- bolts with locking devices

- preloaded bolts

- injection bolts

- other types of bolt which effectively prevent movement of the connected parts

(2) Where slip is not acceptable in a joint (because it is subject to reversal of shear load or for any other reason), preloaded bolts in a Category B or C connection (see 3.4), fit bolts (see 3.6.1), rivets or welding should be used.

(3) For wind and/or stability bracings, bolts in Category A connections (see 3.4) may be used.

2.7 Eccentricity at intersections

(1) Where there is eccentricity at intersections, the joints and members should be designed for the resulting moments and forces, except in the case of particular types of structures where it has been demonstrated that it is not necessary, see 5.1.5.

(2) In the case of joints of angles or tees attached by either a single line of bolts or two lines of bolts any possible eccentricity should be taken into account in accordance with 2.7(1). In-plane and out-of-plane eccentricities should be determined by considering the relative positions of the centroidal axis of the member and of the setting out line in the plane of the connection (see Figure 2.1). For a single angle in tension connected by bolts on one leg the simplified design method given in 3.10.3 may be used.

NOTE: The effect of eccentricity on angles used as web members in compression is given in EN 1993-1-1, Annex BB 1.2.

Figure 2.1: Setting out lines

1 Centroidal axes

2 Fasteners

3 Setting out lines

Figure 2.1: Setting out lines

2.8 References

This European Standard incorporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard, only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies (including amendments).

Reference Standards, Group 1 : Weldable structural steels prEN 10025:2001 Hot rolled products of non-alloy structural steels - Technical delivery conditions

Reference Standards, Group 2: Tolerances, dimensions and technical delivery conditions

EN 10029:1991

EN 10034:1993 EN 10051:1991

EN 10055:1995

EN 10056-1:1995 EN 10056-2:1993

EN 10164:1993

Hot rolled steel plates 3 mm thick or above - Tolerances on dimensions, shape and mass

Structural steel I- and H-sections - Tolerances on shape and dimensions

Continuously hot-rolled uncoated plate, sheet and strip of non-alloy and alloy steels -Tolerances on dimensions and shape

Hot rolled steel equal flange tees with radiused root and toes - Dimensions and tolerances on shape and dimensions

Structural steel equal and unequal leg angles - Part 1: Dimensions

Structural steel equal and unequal leg angles - Part 2: Tolerances on shape and dimensions

Steel products with improved deformation properties perpendicular to the surface of the product - Technical delivery conditions

Reference Standards, Group 3: Structural hollow sections

Cold formed welded structural hollow sections of non-alloy and fine grain steels - Part 1: Technical delivery requirements

Cold formed welded structural hollow sections of non-alloy and fine grain steels - Part 2: Tolerances, dimensions and sectional properties

Hot finished structural hollow sections of non-alloy and fine grain structural steels -Part 1: Technical delivery requirements

Hot finished structural hollow sections of non-alloy and fine grain structural steels -Part 2: Tolerances, dimensions and sectional properties

EN 10219-1:1997 EN 10219-2:1997 EN 10210-1:1994 EN 10210-2:1997

Reference Standards, Group 4: Bolts, nuts and washers

EN 14399-1:2002 High strength structural bolting for preloading - Part 1 : General Requirements

High strength structural bolting for preloading - Part 2 : Suitability Test for preloading

High strength structural bolting for preloading - Part 3 : System HR -Hexagon bolt and nut assemblies

EN 14399-2:2002 EN 14399-3:2002

EN 14399-4:2002

High strength structural bolting for preloading - Part 4 : System HV -Hexagon bolt and nut assemblies

EN 14399-5:2002 EN 14399-6:2002

EN 20898-2:1993

EN ISO 2320:1997

High strength structural bolting for preloading - Part 5 : Plain washers for system HR

High strength structural bolting for preloading - Part 6 : Plain chamfered washers for systems HR and HV

EN ISO 898-1:1999 Mechanical properties of fasteners made of carbon steel and alloy steel - Part 1: Bolts, screws and studs (ISO 898-1:1999)

Mechanical properties of fasteners - Part 2: Nuts with special proof load values -Coarse thread (ISO 898-2:1992)

Prevailing torque type steel hexagon nuts - Mechanical and performance requirements (ISO 2320:1997)

Hexagon head bolts - Product grades A and B (ISO 4014:1999) Hexagon head bolts - Product grade C (ISO 4016:1999) Hexagon head screws - Product grades A and B (ISO 4017:1999) Hexagon head screws - Product grade C (ISO 4018:1999) Hexagon nuts, style 1 - Product grades A and B (ISO 4032:1999) Hexagon nuts, style 2 - Product grades A and B (ISO 4033:1999) Hexagon nuts - Product grade C (ISO 4034:1999)

Prevailing torque hexagon nuts (with non-metallic insert), style 1 - Property classes 5, 8 and 10

Prevailing torque all-metal hexagon nuts, style 2 - Property classes 5, 8, 10 and 12

Prevailing torque type all-metal hexagon nuts, style 1 - Property classes 5, 8 and 10

ISO system of limits and fits - Part 2: Tables of standard tolerance grades and limit deviations for hole and shafts

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