1

Rolled I section

1 Flexure

2 Axial compression

5 Axial compression

6 Flexure

7 Flexure and

□ axial compression

1 Flexure " 2 Axial compression

5 Axial compression

6 Flexure

7 Flexure and axial compression

Built-up I section

3 Flexure or axial compression

Hollow structural tube

8 Flexure or axial compression _ 2 Flexure and axial compression

Hollow structural tube

Longitudinally stiffened built-up box section

1 Flexure

2 Axial compression

1 Flexure

2 Axial compression

. 5 Axial compression

6 Flexure

7 Flexure and axial compression

Built-up channels

FIGURE 20.27 Selected steel cross-sections [36].

5 Axial compression

6 Flexure

7 Flexure and axial compression

Built-up box

Built-up box

5 Flexure

6 Axial compression

5 Axial compression

6 Flexure

7 Flexure and axial compression

TABLE 20.14 Caltrans Limiting Slenderness Parameters [36]

Member classification

Limiting slenderness parameters

Ductile

Compression member Flexural member

Capacity protected Compression member Flexural member

0.75 17240/Fy y

1.5 ffiffiffiffi:

Notes:

1c — (KL/rp)\/(Fy/E) (slenderness parameter for compression members).

lb — L/ry (slenderness parameter for flexural members).

lcp — limiting slenderness parameter for compression members.

lbp — limiting slenderness parameter for flexural members.

K — effective length factor of a member.

ry — radius of gyration about the minor axis (mm).

Fy — specified minimum yield strength of steel (MPa).

E — modulus of elasticity of steel (200,000 MPa).

0 0

Post a comment