You are currently reviewing an older revision of this page.
Document Information
Document Type: FAQ
Product(s): LEAP BRIDGE STEEL
Version(s): All
Original Author: Bentley Technical Support Group -VM
QUESTION: How is the program calculating Δf -- Fatigue stress range and the related Performance Ratio?
ANSWER:
Δf = fatigue stress range.
Delta_f = (Mzp – Mzn) * Ybar_bottom_of_the_web / Iz
Mzp = Max positive moment
Mzn = Max negative moment
Performance ratio = 0.75*4.192 / 1.924 = 1.634