Building Design and Construction Handbook - Merritt - Ventech!

STRUCTURAL STEEL CONSTRUCTION 7.79
TABLE 7.19 Bearing on Finished
Surfaces, ksi
Allowable
stress (ASD)
F y
F p
F y
Design strength
(LRFD)
�Rn/A pb
36 32.4 36 54.0
42 37.8 42 63.0
45 40.5 45 67.5
50 45.0 50 75.0
55 49.5 55 82.5
60 54.0 60 90.0
TABLE 7.20 Allowable Bearing Loads on
Expansion Rollers or Rockers, kips per in
of Bearing
F y
Allowable
load (ASD)
F p
Design strength
(LRFD)
F y
�R* n
36 0.76d 36 1.30d
42 0.96d 42 1.64d
45 1.06d 45 1.81d
50 1.22d 50 2.08d
55 1.39d 55 2.37d
60 1.55d 60 2.64d
* d is the diameter, in. of the roller or rocker.
TABLE 7.21 Allowable Bearing on Masonry, ksi
On sandstone and limestone 0.40
On brick in cement mortar 0.25
On the full area of concrete 0.35ƒ� c
On less than full concrete area 0.35ƒ� �A /A � 0.7ƒ�
c 2 1 c
where ƒ�c � specified compressive strength, ksi, of the concrete
A1 � bearing area
A2 � concrete area
LRFD Procedure for Bearing. The design strength in bearing on the projected
bearing area for finished surfaces, such as milled ends and ends of bearing stiffeners,
or on the projected area of pins in finished holes, is �R n, where � � 0.75.
R � 2.0F A (7.53)
n y pb
where F y is the lesser minimum yield stress, ksi, of the steel (Table 7.19) and A pb
is the projected bearing area, in 2 .