🌉 Висячий мост (Long-Span Suspension Bridge)

Модуль #307. Концепт «Yellow River Bridge» Алтай (предлагаемый), а также reference world records: Akashi Kaikyo Japan main span 1991 m (1998), 1915 Çanakkale Turkey 2023 m (2022), Great Belt Denmark 1624 m, Verrazzano-Narrows USA 1298 m, Golden Gate 1280 m. Suspension bridge — главный кабель из 30 000-50 000 high-tensile steel wires Ø5 mm draped over two pylons + hangers vertical to deck. Aerodynamic instability (Tacoma Narrows 1940) requires wind tunnel testing + truss/box girder design. AASHTO LRFD + Eurocode EN 1993 + СН РК 5.04-10.

1. Состав bridge 1200 m main span

Pylons (towers) H=220 м ж/б B60 + steel frame composite, foundation caisson Ø40 м H=60 м;
Main cable Ø600 мм parallel-wire strands PWS, 30 000 wires Ø5 мм high-tensile steel 1860 МПа, 90 strands × 333 wires each;
Cable wrapping galvanized + paste для corrosion + 3-layer paint;
Anchor block ж/б В60 50×40×30 м (60 000 т) embedded в подстилка через rock anchors;
Hangers Ø100 мм Cu-coated high-strength steel rods 10-30 м spacing along main span;
Deck steel orthotropic box-girder 35 m wide × 4.5 m high welded SM490 plate 14-25 мм;
Aerodynamic shape — streamlined trapezoid через wind tunnel test scale 1:50 ChinaCAFE 2022;
Stay cables for cable-stayed approach segments (если hybrid design);
Tuned Mass Dampers TMD на pylon top 200-500 т suppress vortex shedding;
Expansion joints Maurer XLN-1500 для 1500 мм movement summer-winter;
Wind monitoring 6 anemometers Vaisala WMT700 каждые 200 м;
Structural Health Monitoring SHM — 200+ strain gauges + accelerometers + displacement sensors;
Cathodic protection ICCP anchor blocks + main cable + deck;
Inspection gondola travel rail along underside deck для maintenance;
Lighting + aviation warning red flashing on pylon top per ICAO Annex 14.

Упражнение 1 — Bridge type для 1200 m span

Beam bridge монолитный из ж/б — простойArch bridge как Старый КаирскийTruss bridge стальнойSuspension bridge с aerodynamic box-girder deck + TMD для 1200 m span: (1) только cable-stayed возможно до ~1000 м эффективно, suspension до 2000+ м (1915 Çanakkale 2023), (2) main cable parallel-wire 30 000 wires Ø5 мм high-tensile carry deck dead load + live load + wind, (3) aerodynamic box-girder streamlined shape minimises vortex shedding induced flutter (Tacoma Narrows lesson 1940), (4) wind tunnel testing scale 1:50-100 за 12-18 месяцев для verify critical wind speed > design + 30% safety, (5) TMD Tuned Mass Damper 200-500 т на pylon top для damping resonance frequencies; (6) anchor blocks ж/б 50 000-100 000 т соответствуют tensile force в кабеле ~1 ГН; AASHTO LRFD + Eurocode EN 1993

Упражнение 2 — Main span length

Для прохода судов Ø1000 m clearance + safety margin. Spam length (м)?

Упражнение 3 — Капекс 1200 m bridge

Pylons 2× H=220 м ж/б + steel composite + caisson foundation = 95 млрд
Main cable 30 000 wires PWS + erection = 120 млрд
Anchor blocks 2× 60 000 т ж/б + rock anchoring = 65 млрд
Box-girder deck 1200 м × 35 м × 50 тыс. т steel SM490 = 75 млрд
Hangers + saddles + dampers TMD = 18 млрд
Wind tunnel + aerodynamic testing + SHM monitoring = 8 млрд
Approach spans + expansion joints + lighting + safety + проект 6% + ESIA + PNR + insurance = 39 млрд

Упражнение 4 — Aeroelastic stability

Никакого учёта ветраТолько статический wind loadComprehensive aerodynamic analysis per AASHTO LRFD + IABSE Wind Engineering: (1) wind tunnel testing scale 1:50-100 sectional model + full bridge aeroelastic model за 12-18 мес, critical wind speed flutter onset > design wind 150% safety margin, (2) box-girder shape streamlined trapezoid lessons learned Tacoma Narrows 1940 (плоское deck → vortex-induced flutter); (3) Tuned Mass Dampers TMD 200-500 т на pylon top tuned to dominant frequencies 1-2 Hz, suppress resonance, (4) buffeting analysis для random wind turbulence using power spectral density PSD; (5) galloping mode для cable structures; (6) full-scale wind monitoring 6 anemometers continuously, automatic shutdown bridge при wind >150 km/h; AASHTO LRFD + Eurocode EN 1993 + IABSE + JSCE + EN 1991-1-4 + СН РК 5.04-10Закрыть мост при ветре

Нормативная база

AASHTO LRFD Bridge Design Specifications 9th
Eurocode EN 1993-2 Steel Bridges
EN 1991-1-4 Wind Loads on Structures
JSCE Cable Stay Bridge Specifications
IABSE Long-Span Cable Structures
СН РК 5.04-10 Мосты
FHWA Bridge Design Manual
ASTM A586 — Bridge Strand Wire