Mechanical Properties

Mechanical properties of angles and bolts used in numerical analysis are listed in Table 2. The mechanical properties of angles for all connection models except models FE7 and FE7np are the

Test or FEA model

Top and seat angles

Bolt

Yield stress °v

(MPa)

Ultimate strength <ju (MPa)

Yield stress

°y, b

(MPa)

Ultimate strength <ju>h (MPa)

Test 3

297

517

635

830

Al, A2, FE1-FE6, FE9-FE13, Alnp, A2np, FElnp~FE4np, FE9np~FE13np

365

550

635

830

FE7, FE7np

250

400

FE8, FE8np

365

550

830

1,035

Fig. 3. Stress-strain relationship for steel used in this analysis.

same among them, which are taken from the test data for experiments conducted by Azizinamini et al. (1985). To investigate the effects of mechanical properties of angle on prying action, those for models FE7 and FE7np are assumed to be equal to the nominal values of A36 steel. Yield stress and ultimate strength of steel for beam, column and angles of all connection models are assumed to be 365 MPa and 550 MPa, respectively. Mechanical properties for bolts of all connection models except models FE8 and FE8np are assumed to be the nominal values of A325 bolts and those for models FE8 and FE8np are assumed to be equal to the nominal values of A490 bolts following the AISC-LRFD specifications because no coupon test results were reported yet. A bilinear elasto – plastic stress-strain relationship with isotropic hardening rule is assumed for all connection members taking Young’s modulus of elasticity E = 206 GPa and Poisson’s ratio v = 0.3 as shown in Figure 3. Here, ultimate strain su is assumed to be 10% for bolt and 20% for another connection components.