Question

A bearing plate is used to support each end of a W16x100 beam. The plate has dimensions of 18"x18"x1-1/4” and rests on 1500-psi concrete pedestals, which are 20”x20”. Determine the maxi- mum factored reaction that the plate can support. The beam itself is known to be adequate, so you just need to check the bearing plate and the concrete pedestal. Recall that the thickness of the bearing plate is governed by: 2.2R,n2 BloFy and the factored capacity of a concrete support is (P = 0.65): OP, = 0 (0.85A1 A2/A1) with A2/A1 <2

Answer 1

Complete solution is given below.

Given: kl 16 x 100 From AISC manual d= 7" be 10.4 K= 1.39 17 thickney of bearing plate 2.2 Rn n? t = Blb Fy plate given 18 X 18 X 1.25 in t = coas Fy = 36 ksi 18 B = l6 = 18 na Brak 2 7.61 18 - CRX 1.39) Substituting all values in above equation. 1.25 = 2 Q.2x Ru x 7.61 18 x 18 x 36 Ru= 143.046k

2) capacity of concrete pedestal $ fn = ¢ (0.85 fe' A, A2/AL) . plate area < Concrete area 4 324 in ² 400 in 1.5 ksi O. 65 Ai = 18x18 Az = = 20 x 20 = f 6 Az 400 А, 324 . 1.23 < 2 Ok i Substituting all the values un above equation & Pn = 0.65 (0.85 (0.85*115* 324 * ($Pw = 298.35k - 324 Therefore, Maximum factored weachion Ru= 143.046 k