Slotted Holes Sizes Ec

Spacing p2 5)

2,44o

The smaller of 14t or 200 mm

The smaller of 14t or 200 mm

The smaller of 14tmin or 175 mm

Maximum values for spacings, edge and end distances are unlimited, except in the following cases:

- for compression members in order to avoid local buckling and to prevent corrosion in exposed members and;

- for exposed tension members to prevent corrosion.

The local buckling resistance of the plate in compression between the fasteners should be calculated according to EN 1993-1-1 using 0,6 pi as buckling length. Local buckling between the fasteners need not to be checked if p\lt is smaller than 9 s . The edge distance should not exceed the local buckling requirements for an outstand element in the compression members, see EN 1993-1-1. The end distance is not affected by this requirement.

t is the thickness of the thinner outer connected part.

The dimensional limits for slotted holes are given in 2.8 Reference Standards: Group 7.

For staggered rows of fasteners a minimum line spacing of p2 = 1,240 may be used, provided that the minimum distance, L, between any two fasteners is greater than 2,4q0, see Figure 3.1b)._

Limit States Affected Staggered Bolts

a) Symbols for spacing of fasteners

Staggered Rows offasteners b) Symbols for staggered spacing a) Symbols for spacing of fasteners

Slotted Hole Dimensions

pi < 14 t and < 200 mm p2 < 14 t and < 200 mm < 14 t and < 200 mm p1,i < 28 t and < 400 mm

1 outer row ! innerrow c) Staggered spacing - compression d) Spacing in tension members

Slot Hole Aisc

e) End and edge distances for slotted holes

Figure 3.1: Symbols for end and edge distances and spacing of fasteners e) End and edge distances for slotted holes

Figure 3.1: Symbols for end and edge distances and spacing of fasteners

3.6 Design resistance of individual fasteners 3.6.1 Bolts and rivets

(1) The design resistance for an individual fastener subjected to shear and/or tension is given in Table 3.4.

(2) For preloaded bolts in accordance with 3.1.2(1) the design preload, Ap,Cd ,to be used in design calculations should be taken as:

NOTE: Where the preload is not used in design calculations the guidance given in the note to Table 3.2 should be followed.

(3) The design resistances for tension and for shear through the threaded portion of a bolt given in Table 3.4 should only be used for bolts manufactured in conformity with 2.8 Reference Standard: Group 4. For bolts with cut threads, such as anchor bolts or tie rods fabricated from round steel bars where the threads comply with EN1090, the relevant values from Table 3.4 should be used. For bolts with cut threads where the threads do not comply with EN1090 the relevant values from Table 3.4 should be multiplied by a factor of 0,85.

(4) The design shear resistance ^v,Rd given in Table 3.4 should only be used where the bolts are used in holes with nominal clearances not exceeding those for normal holes as specified in 2.8 Reference Standards: Group 7.

(5) M12 and M14 bolts may also be used in 2 mm clearance holes provided that the design resistance of the bolt group based on bearing is greater or equal to the design resistance of the bolt group based on bolt shear. In addition for class 4.8, 5.8, 6.8, 8.8 and 10.9 bolts the design shear resistance .Fv,Rd should be taken as 0,85 times the value given in Table 3.4.

(6) Fit bolts should be designed using the method for bolts in normal holes.

(7) The thread of a fit bolt should not be included in the shear plane.

(8) The length of the threaded portion of a fit bolt included in the bearing length should not exceed 1/3 of the thickness of the plate, see Figure 3.2.

(9) The hole tolerance used for fit bolts should be in accordance with 2.8 Reference Standards: Group 7.

(10) In single lap joints with only one bolt row, see Figure 3.3, the bolts should be provided with washers under both the head and the nut. The design bearing resistance ^b,Rd for each bolt should be limited to:

NOTE: Single rivets should not be used in single lap joints.

(11) In the case of class 8.8 or 10.9 bolts, hardened washers should be used for single lap joints with only one bolt or one row of bolts.

(12) Where bolts or rivets transmitting load in shear and bearing pass through packing of total thickness tp greater than one-third of the nominal diameter d, see Figure 3.4, the design shear resistance ^v,Rd calculated as specified in Table 3.4, should be multiplying by a reduction factor [>v given by:

(13) For double shear connections with packing on both sides of the splice, tp should be taken as the thickness of the thicker packing.

(14) Riveted connections should be designed to transfer shear forces. If tension is present the design tensile force ^t.Ed should not exceed the design tension resistance _Ft,Rd given in Table 3.4.

(15) For grade S 235 steel the "as driven" value of/ur may be taken as 400 N/mm2.

(16) As a general rule, the grip length of a rivet should not exceed 4,5d for hammer riveting and 6,5d for press riveting.

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