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(2) The design tension resistance -Fx,i,Rd of the left side of the joint should be taken as the smallest values of the design resistance of following basic components:

- the column web in tension under the left column flange AtwcRd - see 6.2.6.3;

- the base plate in bending under the left column flange At,pl,Rd - see 6.2.6.11.

(3) The design tension resistance AT,rRd of the right side of the joint should be taken as the smallest values of the design resistance of following basic components:

- the column web in tension under the right column flange AtwcRd - see 6.2.6.3;

- the base plate in bending under the right column flange At,plRd - see 6.2.6.11.

(4) The design compressive resistance ^c,l,Rd of the left side of the joint should be taken as the smallest values of the design resistance of following basic components:

- the concrete in compression under the left column flange Ac,plRd - see 6.2.6.9;

- the left column flange and web in compression Ac,fc,Rd - see 6.2.6.7.

(5) The design compressive resistance AC,rRd of the right side of the joint should be taken as the smallest values of the design resistance of following basic components:

- the concrete in compression under the right column flange Ac,plRd - see 6.2.6.9;

- the right column flange and web in compression AcfcRd - see 6.2.6.7.

(6) For the calculation of zTl, zCl, zT,r, zC,r see 6.2.8.1.

Table 6.7: Design moment resistance Mj,Rci of column bases

Loading

Lever arm z

Design moment resistance Mj,Rd

Left side in tension Right side in compression

Z = "T,l + "C,r

1Ed > 0 and e > zT l

1Ed < 0 and e < -zC,r

The smaller of-and-

z(. J e +1 zrx! e -1

Left side in tension Right side in tension

" = "T,l + "T,r

1Ed > 0 and 0 < e < zT l

1Ed > 0 and -zT,r < e <0

The smaller of

A,1,M " ___, A,r,Rd Z

The smaller of

A\1,Rd " ___, Ar,1^ "

z7v / e +1 z7,,1 / e -1

z7v / e +1 ^,,1 / e -1

Left side in compression Right side in tension

" = "C,l + "T,r

NEd > 0 and e < -zT,r

NEd < 0 and e > zC l

m. ,, ,, AC,1,Rd " , Ar,r,M " The smaller of- and-

"v / e +1 z0 / e-1

Left side in compression Right side in compression

" = "C,l + "C,r

NEd < 0 and 0 < e < zC l

NEd < 0 and -zC,r < e <0

The smaller of

— AC,1,Rd Z___, — AC,r,Iid Z

The smaller of

— AC,1,M Z___, — AC,r,Rd Z

zc J e +1 zr1/ e -1

zc r/ e +1 zr1/ e -1

HEd > 0 is clockwise, NEd > 0 is tension c _ MRd

NM nm

(1) The rotational stiffness of a joint should be determined from the flexibilities of its basic components, each represented by an elastic stiffness coefficient X, obtained from 6.3.2.

NOTE: These elastic stiffness coefficients are for general application.

(2) For bolted end-plate connections with more than one row of bolts in tension, the stiffness coefficients X for the related basic components should be combined. For beam-to-column joints and beam splices a method is given in 6.3.3 and for column bases a method is given in 6.3.4.

(3) In a bolted connection with more than one bolt-row in tension, as a simplification the contribution of any bolt-row may be neglected, provided that the contributions of all other bolt-rows closer to the centre of compression are also neglected. The number of bolt-rows retained need not necessarily be the same as for the determination of the design moment resistance.

(4) Provided that the axial force 1Ed in the connected member does not exceed 5% of the design resistance iVpE>Rd of its cross-section, the rotational stiffness .V, of a beam-to-column joint or beam splice, for a moment Mj,Ed less than the design moment resistance Mj,Rd of the joint, may be obtained with sufficient accuracy from:

where:

X is the stiffness coefficient for basic joint component i;

U is the stiffness ratio Sj,ini I Sj , see 6.3.1 (6);

NOTE: The initial rotational stiffness Sj,ini of the joint is given by expression (6.27) with ju = 1,0.

(5) The rotational stiffness Sj of a column base, for a moment Mj,Ed less than the design moment resistance Mj,Rd of the joint, may be obtained with sufficient accuracy from 6.3.4.

(6) The stiffness ratio u should be determined from the following:

in which the coefficient y/ is obtained from Table 6.8.

Type of connection

0 0

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