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 Quizzes
PE-style chapter quizzes
Multi-step numeric items with stacked LaTeX derivations and inline figures. Passing score is 70%. Attempts are saved to your progress transcript when signed in.
Ch 1
Bridge functions, classifications, systems, and the design–build–inspect lifecycle. Overview of AASHTO LRFD, engineering ethics, and how bridges fit into the transportation network.
Ch 2
Evolution from ASD to LFD to LRFD. Reliability, load and resistance factors, ductility, redundancy, operational importance, and the four AASHTO limit states.
Ch 3
Permanent and transient loads, HL-93 live loading, dynamic load allowance, multiple-presence factors, braking and centrifugal effects, and Strength / Service / Fatigue / Extreme-Event combinations. Includes a full three-span Mid-Atlantic bridge worked example.
Ch 4
Load paths, influence lines and surfaces, live-load distribution factors, approximate methods vs. refined analysis, grillage and finite-element models, and validation.
Ch 5
AASHTO equivalent-strip method, empirical design, minimum reinforcement and cover, distribution steel, crack control, and Extreme Event II overhang design. Complete concrete-deck worked example plus a full steel orthotropic-deck example with the three stress systems (local, panel, global) and rib-to-deck weld fatigue check.
Ch 6
Solid slab, T-beam, and RC box-girder bridge design. Effective flange width, Whitney stress block flexural design, AASHTO simplified sectional shear method, torsion in boxes, and detailing. Includes a full T-beam worked example (flexure + shear + fatigue + deflection) and a solid slab bridge example, plus a two-span continuous T-beam design challenge.
Ch 7
Pre-tensioned and post-tensioned girder design. Losses, transfer and service stresses, flexural and shear strength (§5.7, §5.8, §5.9), harped and debonded strand layouts, end-zone anchorage-zone design, deflection and camber. Includes a full AASHTO Type-VI girder worked example, a spliced post-tensioned example, and a mini design challenge.
Ch 8
Rolled and welded plate composite steel girders. Section classification, plastic and yield-moment resistance, LTB, shear with tension-field action, shear stud design, and Category-C fatigue. Includes a full 2×140-ft continuous composite plate-girder worked example and a curved-girder mini design challenge.
Ch 9
Pier and bent classification, load path from superstructure to foundation, slenderness and moment magnification, biaxial P–M interaction for RC columns, bent-cap flexure and shear, and seismic detailing. Includes a full multi-column bent worked example, a hammerhead pier example, and a bent design challenge.
Ch 10
Bearing families (elastomeric, pot, disc, spherical), Method-A design of a steel-reinforced elastomeric pad, joint movement from thermal + shrinkage + creep, and joint-family selection (strip-seal, modular, finger). Full worked examples for an elastomeric bearing pad and a strip-seal joint plus a curved-bridge design challenge.
Ch 11
High-strength bolted and welded connections per AASHTO §6.13. Bolted field splices (75 %-of-yield rule, flange direct force, web elastic-vector), cross-frame families and spacing, top-flange lateral bracing during construction, and gusset-plate design. Worked examples for a bolted flange splice and a cross-frame diagonal plus a 3-span composite design challenge.
Ch 12
Abutment families (stub, seat, cantilever, MSE), Rankine active earth pressure, live-load surcharge, and stability checks for sliding, overturning, and bearing. Cantilever stem/toe/heel design, wingwalls, approach slabs, and integral abutment thermal demand. Two worked examples plus a river-crossing design challenge.
Ch 13
Spread footings, driven piles, drilled shafts, and micropiles per AASHTO §10. Meyerhof bearing capacity, α/β pile methods, O'Neill–Reese rock socket, p-y lateral analysis, group efficiency, and downdrag. Full worked examples for a spread footing and a driven pile group plus a river-crossing drilled-shaft design challenge.
Ch 15
AASHTO seismic hazard, design response spectrum, single-mode SDOF analysis, response modification factor R, plastic-hinge detailing and spiral confinement, capacity-design hierarchy, and seismic isolation. Two worked examples (design base shear and plastic-hinge confinement) plus a four-span SDC-D design challenge.
Ch 16
AASHTO §3.8 wind pressure and aeroelastic screening (buffeting, vortex shedding, flutter), §3.14 vessel-impact Method II, §3.6.5 vehicular collision, §3.9 ice loads, Extreme Event I/II combinations, and multi-hazard resilience framing. Two worked examples (wind pressure and barge impact) plus a cable-stayed multi-hazard design challenge.
Ch 18
Construction engineering for bridges — erection schemes (span-by-span, balanced cantilever, incremental launching, cable-stayed cantilever), formwork and falsework, camber, temporary works, construction loads and combinations, and rigging/lifting. Two worked examples (falsework check + segmental balanced-cantilever unbalanced moment) and a full girder-erection design challenge.
Ch 19
NBIS 23 CFR 650 inspection program (routine, in-depth, fracture-critical, underwater, damage, special), FHWA NBI condition ratings 0–9, common deterioration mechanisms and NDT toolbox, and AASHTO MBE §6A Load and Resistance Factor Rating — Design (Inventory + Operating), Legal, and Permit — with a worked example on a deteriorated composite plate girder and a full 3-span river-crossing evaluation design challenge.
Ch 20
FHWA intervention hierarchy (preservation · rehabilitation · replacement), deck treatments (crack seal, thin polymer, LMC, HMA + membrane), superstructure retrofits (FRP confinement per ACI 440.2R, external post-tensioning, drill-stop + bolted splice for fatigue), substructure jacketing, and life-cycle cost analysis at real discount rates. Full external-PT worked example, a 3-span overpass rehab design challenge, and a PE-format graded quiz.