ON THE EFFECTS OF CIRCULAR BOLT PATTERNS ON THE ...

Element
Washer
Bolt
Line
Number
Table 4-1 The Mesh Size Distribution In The Bolts
Number of
Seeds
W1 20
W2 15
B1 15
B2 10
B3 15
B4 4
46
Schematic
A typical meshed bolt is presented in Figure 4-1. The element type C3D6 was used for both the bolt-
head and the bolt-shank. The nuts were modeled similar to the bolt-head while the extended length of the
bolt beyond each nut was ignored. The nut and the bolt-head were considered as a single body with bolt
shank. The threaded part of the bolt shank was ignored and the bolt shank was replaced with a cylinder
with a nominal diameter of the bolt. Washers were placed on both ends of the bolt (nut and bolt-head) to
simulate the actual experimental specimen. The length of the bolt was set equal to the actual bolt length
for each specimen. The pre-tensioning bolt-force was modeled by applying an initial displacement to two
parallel surfaces in the bolt-shank, using bolt-force with adjustments length function of the ABAQUS 6-
10.1. The value of the initial displacement was adjusted by trial and error to achieve a sufficient pre-
tensioning bolt-force as specified by AISC design manual [53]. The bolts were pre-tensioned in the first
step load and the displacement control loads were applied to the specimen during the next steps.