This educational application supplements, but does not replace, the official AASHTO LRFD Bridge Design Specifications, applicable state DOT manuals, project specifications, and professional engineering judgment.
Graded quiz
Chapter 6 — Reinforced-Concrete Bridge Superstructures (15 questions)
15 questions · PE-exam format · 70% to pass · attempts save to your progress record when signed in.
Work each item to the requested precision. Use the Show clue button only after an honest attempt — hints reveal the AASHTO section and setup, not the answer.
- Q1
Compute a for A_s = 5.0 in², f_y = 60 ksi, f′_c = 4 ksi, b = 14 in (in).
inWhitney block
- Q2
For the same beam with d = 27 in, compute φM_n (k-ft), φ = 0.90.
k-ftRC beam
- Q3
Neutral axis depth c for a = 6.30 in, β₁ = 0.85 (in).
in - Q4
Extreme-fiber steel strain ε_t for c = 7.41 in, d = 27 in.
- - Q5
Tension-controlled behavior for AASHTO Grade 60 requires ε_t ≥ …
- Q6Effective flange width for an interior T-girder in older AASHTO used the minimum of which three?
- Q7
Interior T-beam with S = 9 ft, t_s = 8 in, b_w = 14 in, L = 90 ft; effective flange width (in).
in - Q8
Simplified V_c for b_w = 14 in, d_v = 27 in, f′_c = 4 ksi, β = 2 (kip).
kip - Q9
Required stirrup spacing for V_s = 150 kip, A_v = 0.40 in², f_y = 60 ksi, d_v = 27 in (in).
in - Q10Maximum stirrup spacing per AASHTO §5.7.2.6 when v_u < 0.125 f′_c:
- Q11
Modulus of rupture f_r for f′_c = 4 ksi (ksi).
ksi - Q12
Cracking moment M_cr for I_g = 12,000 in⁴, y_t = 9 in, f_r = 0.48 ksi (k-ft).
k-ft - Q13
Crack-control maximum bar spacing for Class 1 (γ_e = 1.0), f_ss = 30 ksi, d_c = 1.5 in, h = 8 in (in).
in - Q14AASHTO minimum reinforcement rule (§5.6.3.3) requires the factored moment resistance to be greater than the lesser of:
- Q15
Modulus of elasticity of 5-ksi normal-weight concrete (ksi) using E_c ≈ 1820√f′_c.
ksi
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