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CELE Transportation & Highway EngineeringPorts, Harbors, Airports and RailroadsCheat Sheet

Ports, Harbors, Airports and Railroads cheat sheet — the reference card you wish you had on exam day. Condensed from the full study notes, this is the high-yield core of Ports, Harbors, Airports and Railroads for CELE Transportation & Highway Engineering. Download, print, revise.

Exam context

On the CELE 2026, the Transportation & Highway Engineering subtest carries a "Core" weight in Professional Regulation Commission (PRC) — Board of Civil Engineering's pattern. Ports, Harbors, Airports and Railroads lands at position 4th out of 4 in the standard review order. Target score is 70% weighted average, no sub-test below 50%, and roughly a meaningful share of items come from Transportation & Highway Engineering on a typical CELE paper.

Ports, Harbors, Airports and Railroads - Cheat Sheet

Your last-minute rapid-fire reference covering railroad superelevation, airport runway design, and harbor fundamentals. All formulas, key definitions, and exam-critical facts in one condensed resource.

Sections

Formulas

Formula

e = (G × V²) / (127 × R)

Meaning

e = equilibrium cant (m); G = gauge (m); V = train speed (km/h); R = curve radius (m)

Watch Out

Constant 127 is FIXED (same as road superelevation formula). Do NOT confuse gauge (1.435 m standard) with other rail spacing. Speed must be in km/h, radius in meters.

When To Use

Calculate superelevation (cant) on railway curves to balance centrifugal force.

Formula

Maximum cant = e_max (typically 100–150 mm or 0.1–0.15 m)

Meaning

e_max = maximum allowable superelevation set by railway standards and comfort limits

Watch Out

Different railway systems use different e_max values. Philippine railways often use 100–120 mm. Verify from local standards (RA 544 context).

When To Use

Check if calculated cant exceeds maximum; if yes, reduce design speed or increase radius.

Formula

Transition curve length: L_t = (e × G) / gradient_rate, or empirical L_t ≈ 0.5 to 1.0 m/s × V

Meaning

L_t = transition curve length (m); e = cant (m); gradient_rate = rate of cant change per unit length

Watch Out

Abrupt cant change causes 'snapping' and passenger discomfort. Transition curves are ESSENTIAL on sharp curves.

When To Use

Design smooth transition from zero cant (tangent) to full cant (curve) to avoid sudden jerk.

Common Values

Value

1.435 m

Symbol

G

Quantity

Standard gauge

Value

0.10–0.15 m (100–150 mm)

Symbol

e_max

Quantity

Maximum equilibrium cant (typical)

Value

1.5–3.0%

Symbol

m

Quantity

Ruling gradient (typical)

Value

300–500 m

Symbol

R_min

Quantity

Minimum curve radius (freight)

Value

100–160 km/h

Symbol

V

Quantity

Design speed for mainline passenger

Section Title

Railroad Engineering

Important Facts

  • Standard railway gauge (1.435 m) used worldwide except Russia/CIS (1.520 m), Spain/Portugal (1.668 m), Japan (1.067 m).
  • Cant formula constant 127 applies to km/h and m units (same as road superelevation).
  • Equilibrium cant occurs when centrifugal force is exactly balanced; faster trains need more cant.
  • Passenger comfort limit ≈ 0.15 m/s² unbalanced lateral acceleration; freight can tolerate higher.
  • Ruling gradient limits train load; steeper sections require lighter consist or helper engines.
  • Transition curves prevent sudden acceleration jerk; length typically 0.5 to 1.0 m/s × speed in SI units.
  • Railway curves sharper than ~600 m radius require check rails to prevent derailment.
  • Vertical curves (summit/sag) on railways similar to road design but steeper gradients allowed (±2–3%).

Key Definitions

Term

Gauge

Example

Philippine narrow-gauge lines use 1.0 m or 0.75 m; standard gauge = 1.435 m.

Definition

Distance between inside faces of two rails; standard international gauge = 1.435 m (4 ft 8.5 in).

Term

Superelevation (Cant)

Example

A 200 mm cant means the outer rail is 200 mm higher than the inner rail.

Definition

Tilting of the outer rail above the inner rail on a curve to counteract centrifugal force and reduce lateral acceleration.

Term

Ruling Gradient

Example

2% ruling gradient typical for freight lines; steeper gradients require helper engines or reduced load.

Definition

The maximum sustainable gradient on a railway line; determines the heaviest load a train can haul on any section.

Term

Check Rails (Guard Rails)

Example

Used on tight curves (R < 600 m) to prevent lateral wheel slip during high-speed or loaded passage.

Definition

Additional short rails placed inside the sharp curves to guide wheel flanges and prevent derailment.

Term

Transition Curve

Example

Prevents jolt; commonly 50–100 m long for passenger lines.

Definition

Gradual spiral curve connecting a tangent (zero curvature) to a circular arc (constant radius); cant increases gradually.

Diagrams To Know

  • Cross-section of banked curve showing inner and outer rails, cant angle, and centrifugal force vector.
  • Plan view of transition curve connecting tangent to circular arc; cant spiral diagram.
  • Vertical alignment showing ruling gradient, summit/sag curves, and minimum clearance envelopes.
  • Wheel and flange geometry relative to rails and check rails on sharp curves.

Reactions Or Equations

Note

At equilibrium cant, this = 0. When e is insufficient, outer rail carries extra load (flange wear).

Equation

Unbalanced lateral acceleration = (V²/R) - (g × e/G)

Conditions

On a banked curve; V in m/s, R in m, e and G in m, g = 9.81 m/s²

Formulas

Formula

L_actual = L_basic × (1 + elevation%) × (1 + temperature%) × (1 + gradient%)

Meaning

L_actual = required runway length (m); L_basic = sea-level, ISA, 0% gradient reference length; correction factors applied sequentially

Watch Out

Corrections are MULTIPLICATIVE, not additive. Temperature correction is above ISA standard (15°C – 6.5°C/1000 m), NOT above 15°C flat. Order matters: apply elevation first.

When To Use

Calculate real-world runway length needed based on airport elevation, temperature, and gradient.

Formula

Elevation correction = 7% per 300 m (or 0.023% per 1 m of elevation)

Meaning

Length increase due to thinner air reducing engine/lift performance.

Watch Out

This is an ICAO standard rule. Some contexts use 8% per 300 m for more conservative design. Check local code.

When To Use

For every 300 m of elevation, add 7% to basic runway length.

Formula

Temperature correction = 1% per 1°C above ISA standard for that elevation

Meaning

ISA standard = 15°C – (6.5°C/1000 m × elevation in km); add 1% for each °C above this.

Watch Out

CRITICAL: Do NOT use flat 15°C as baseline. ISA decreases with elevation: 15 – 6.5×(elev/1000)°C. A 1000 m high airport has ISA = 8.5°C.

When To Use

Account for hot-day performance loss; applies only if airport reference temperature exceeds ISA.

Formula

Gradient correction ≈ 1% per 0.1% (or 1% per 0.1% slope gradient)

Meaning

Length increase if runway has significant upslope (average gradient from threshold to far end).

Watch Out

Gradient correction is usually small and often neglected for slopes < 0.5%. Typical corrections: 0–2%.

When To Use

If average runway gradient > 0.5%, apply correction; for landing direction (uphill favors aircraft).

Formula

Wind coverage ≥ 95% (ICAO standard for runway orientation adequacy)

Meaning

The runway orientation should accommodate crosswind for ≥ 95% of the time based on local wind rose.

Watch Out

Crosswind limit for jet transport ≈ 15 m/s (54 km/h); most aircraft limit ≈ 10 m/s. Orientation by wind rose, not runway gradient convenience.

When To Use

Determine optimal runway heading from wind rose data (usually 16-point or 36-point compass rose).

Common Values

Value

7% per 300 m (or 0.023% per meter)

Symbol

ΔL_elev

Quantity

Elevation correction

Value

1% per 1°C above ISA

Symbol

ΔL_temp

Quantity

Temperature correction

Value

1% per 0.1% slope

Symbol

ΔL_grade

Quantity

Gradient correction

Value

≥ 95%

Symbol

Coverage%

Quantity

Wind coverage requirement

Value

10–12 m/s (36–43 km/h)

Symbol

V_xwind

Quantity

Crosswind limit (narrow-body jet)

Value

300 m

Symbol

L_strip

Quantity

Runway strip length (from threshold)

Value

150 m (75 m each side)

Symbol

W_strip

Quantity

Runway strip width (aside)

Value

45 m

Symbol

W_taxiway

Quantity

Taxiway width (mainline)

Section Title

Airport Runway Design

Important Facts

  • ICAO Annex 14 and Philippines Civil Aviation Authority (CAAP) specify runway design standards.
  • Elevation correction: +7% per 300 m is standard; some codes use +8% for conservative design.
  • Temperature correction: +1% per °C ABOVE ISA standard (not above flat 15°C); ISA = 15 – 6.5×(elev/1000)°C.
  • Gradient correction minimal for slopes < 0.5%; typically ignored unless runway is very steep.
  • Wind rose orientation governs runway heading; ≥ 95% wind coverage required for adequate 1-runway system.
  • Crosswind limit ≈ 10 m/s (36 km/h) for typical jets; some larger aircraft ≤ 15 m/s.
  • Runway length corrected successively (multiply factors); order: elevation → temperature → gradient.
  • Taxiway: 45 m width typical for mainline airport; turning radius ≥ 60 m for 90° turn.
  • Runway-to-runway separation for parallel runways ≥ 760 m (independent parallel ops) or ≥ 460 m (dependent).
  • Apron (ramp): 1.5× of runway width typical; strength designed for aircraft wheel loads (Boeing gear pressures ≈ 1.0–1.5 MPa).

Key Definitions

Term

Basic Runway Length (L_basic)

Example

B737: ≈ 2400 m; A380: ≈ 2600–3000 m basic length (from aircraft data).

Definition

Reference takeoff/landing distance at sea level, ISA (15°C), 0% gradient, calm wind, maximum aircraft weight.

Term

Wind Rose

Example

If prevailing winds blow N–S, orient runway N–S to align with wind (headwind for takeoff/landing).

Definition

Radar-style diagram showing frequency and direction of winds at an airport; used to orient runways for maximum wind coverage.

Term

Crosswind Limit

Example

A 15 km/h crosswind on a runway oriented 10° off true wind direction reduces effective headwind slightly.

Definition

Maximum perpendicular wind component an aircraft can safely tolerate during takeoff/landing; typically 10–15 m/s.

Term

ISA (International Standard Atmosphere)

Example

At 1500 m elevation, ISA = 15 – (6.5 × 1.5) = 5.25°C.

Definition

Reference atmosphere: 15°C at sea level, decreasing 6.5°C per 1000 m elevation; used to standardize aircraft performance.

Term

Airport Reference Temperature (ART)

Example

A hot airport (e.g., Manila) may have ART ≈ 32–35°C, requiring significant runway lengthening.

Definition

Mean of the highest daily maximum temperatures in the warmest month over 30 years; used for temperature runway correction.

Term

Runway Strip (Safety Area)

Example

No obstacles, utility poles, or buildings within the strip; must be drained and relatively flat.

Definition

Clear zone extending 300 m (typical) from runway end and 150 m width aside; protects against overrun and undershoot.

Term

Clear Zone

Example

Extends 300 m from runway threshold, widens at 1:20 ratio (or steeper per code).

Definition

Area at runway approach where no obstacles may exist; ensures aircraft can climb safely on takeoff or descend for landing.

Diagrams To Know

  • Wind rose (16-point or 36-point compass) with frequency vectors; optimal runway orientation selection.
  • Runway profile showing elevation change, gradient %, and clearance envelopes from threshold to far end.
  • Runway strip and clear zone cross-section and plan; safety area dimensions.
  • Aircraft approach slope (3° glide slope) with obstacle clearance diagram.
  • Taxiway centerline radius and shoulder fillet geometry for different aircraft categories.

Formulas

Formula

Channel depth = design vessel draft + under-keel clearance

Meaning

Depth measured below lowest astronomical tide (LAT) or chart datum; draft = deepest point of loaded hull; clearance = safety margin (typically 1.0–1.5 m).

Watch Out

Depth is referenced to TIDAL DATUM, not mean water level. LAT (Lowest Astronomical Tide) is the standard reference in most ports. Seasonal/weather variations matter: storm surge, dredge maintenance depths.

When To Use

Determine minimum dredging depth for a harbor to accommodate target vessel class safely.

Formula

Mooring line tension ≈ (wind force + current force + wave force) / (number of lines × line efficiency)

Meaning

Wind load ≈ 0.5 × ρ_air × V² × C_d × projected area; current ≈ similar; wave force dynamic

Watch Out

Wind is highly directional; design for worst-case 100-year wind or port-specific design storm. Current vectors vary with tidal phase. Multiple loading cases required.

When To Use

Size mooring hardware (bollards, bits, cleats) for safe vessel hold during berthing.

Formula

Breakwater height ≥ design wave height + freeboard allowance + setup/runup

Meaning

Design wave = significant wave height (H_s) or H_1/10; freeboard ≈ 0.5–1.5 m above high water; setup/runup depend on slope and wave steepness.

Watch Out

Wave setup and runup ADD to still water level and can exceed design wave height. Steep slopes increase runup. Sheltered vs. open-water design very different.

When To Use

Design breakwater crest elevation to prevent overtopping during design storm (e.g., 50-year return period).

Formula

Turning basin radius ≥ 1.5 × L_ship (minimum) or 2.0 × L_ship (preferred)

Meaning

L_ship = length overall; ratio ensures space for safe 180° turn without excessive rudder angle or dredge damage.

Watch Out

Narrow channels and strong currents reduce effective turning radius. Tugs may be required; basin depth = channel depth. Circular basin preferred over oval.

When To Use

Size circular or oval turning basin at port approaches to allow inbound/outbound vessel rotation.

Formula

Berth length ≥ L_ship + 2 × safety margin (typically 10–15 m per side)

Meaning

Length of wharf/quay face required for vessel mooring with allowance for surge and drift.

Watch Out

Current, wind, and wave surge cause vessel movement; inadequate margin results in collision. Breasting dolphins or fender systems reduce required length.

When To Use

Plan wharf layout and determine number of berths for expected fleet.

Common Values

Value

1.0–1.5 m (large vessels); 0.5–1.0 m (restricted channels)

Symbol

UKC

Quantity

Under-keel clearance

Value

1.5 × L_ship

Symbol

R_turn

Quantity

Turning basin radius (minimum)

Value

2.0 × L_ship

Symbol

R_turn_pref

Quantity

Turning basin radius (preferred)

Value

294 m length × 32 m beam × 15 m draft

Symbol

L × B × d

Quantity

Panamax design vessel

Value

400+ m length × 50+ m beam × 15–16 m draft

Symbol

L × B × d

Quantity

Post-Panamax design vessel

Value

Varies by location (tropical ≈ 2–4 m; temperate ≈ 6–10 m)

Symbol

H_s

Quantity

Breakwater design wave height (50-year return)

Value

50 kPa (general cargo); 100+ kPa (container gantry cranes)

Symbol

q

Quantity

Wharf deck loading

Value

40–60 m (container); 20–30 m (breakbulk)

Symbol

W_apron

Quantity

Apron working width

Section Title

Ports and Harbors

Important Facts

  • Harbor depth reference: Lowest Astronomical Tide (LAT) or Lowest Low Water (LLW); depths shown on nautical charts.
  • Design vessel draft + under-keel clearance = minimum dredged depth; typical clearance 1.0–1.5 m for large vessels, 0.5–1.0 m for restricted channels.
  • Breakwater design: consider 50-year or 100-year return storm; wave height from hindcast/buoy data or fetch-limited formulas (SMB, Pierson–Moskowitz).
  • Mooring forces: wind (dominant in many climates), current (tidal + estuarine flow), wave drift (low-frequency surge), and tide-induced surge all contribute.
  • Turning basin: preferred radius = 2.0 × L_ship; minimum = 1.5 × L_ship. Depth = channel depth (no shoaling).
  • Wharf deck loading: 50 kPa typical for general cargo; 100+ kPa for container cranes; design per ACI 318 or local code.
  • Apron/quay working width: 40–60 m typical for container operations; less for breakbulk.
  • Mooring lines: 4–8 lines typical for general cargo ship; pre-planned arrangement reduces turnaround time.
  • Dredging: maintenance dredging required every 5–10 years depending on silt load; capital dredging for new channel/expansion.
  • Breakwater armor: Dn = D50 stone size; design uses Hudson formula or Van der Meer (wave overtopping criteria).

Key Definitions

Term

Harbor/Port

Example

Manila Harbor (natural) vs. Port of Batangas (partly dredged and protected).

Definition

Sheltered water body (natural or artificial via breakwater) where ships moor, load/unload cargo, and refuel; includes berths, channels, and basins.

Term

Breakwater

Example

Rubble-mound: large boulders/armor units stacked on core; caisson: hollow concrete box filled with grout or sand.

Definition

Offshore structure (rubble-mound, caisson, pile, or composite) that reduces wave energy inside harbor, allowing safe vessel operations.

Term

Wharf/Quay

Example

Typical container terminal wharf: 400–600 m long, 15–20 m deep, reinforced concrete deck for cranes.

Definition

Waterfront structure (sheet pile, gravity, or caisson wall) where vessels tie up, load/unload; supports dock equipment and cargo transfer.

Term

Berth

Example

A 400 m wharf might have 1 large berth for Panamax containers or 2–3 smaller berths.

Definition

Individual mooring space at wharf for one vessel; includes mooring points and fender protection.

Term

Turning Basin

Example

Radius typically 1.5–2.0× ship length; 150 m radius for a 75 m general cargo ship.

Definition

Circular or oval area in a harbor where vessels can rotate 180° without excessive rudder angle or grounding.

Term

Channel (Dredged)

Example

300 m wide, 12 m deep channel for Panamax vessels (9.5 m draft + 2.5 m clearance).

Definition

Artificial waterway connecting harbor to open sea; dredged to design depth and width for safe navigation.

Term

Under-Keel Clearance (UKC)

Example

A 10 m draft ship in a 12 m channel has 2 m UKC.

Definition

Vertical safety margin between vessel draft and channel bottom; typical 1.0–1.5 m for collision/squat protection.

Term

Design Vessel

Example

Panamax (294 m × 32 m, 15 m draft) for major container port; general cargo ship (150 m × 20 m, 8 m draft) for regional port.

Definition

Largest or most restrictive ship class the port is intended to accommodate; defines channel/basin dimensions.

Term

Fender

Example

Cylindrical fender ø 1.5 m absorbs kinetic energy up to ~500 kJ (typical small vessel impact).

Definition

Energy-absorbing cushion (rubber, foam, or pneumatic) attached to wharf face to protect vessel and structure during berthing.

Diagrams To Know

  • Harbor layout: breakwater, channels, turning basin, wharves, aprons (top-down plan view).
  • Cross-section of wharf showing sheet-pile wall, toe foundation, backfill, deck reinforcement, and fender attachment.
  • Breakwater cross-section: core, filter layers, armor stone sizing, and crest elevation.
  • Vessel mooring arrangement: typical 4–8 line configuration, angles, and tension vectors.
  • Typical port profile: fairway depth, channel depth, anchorage zone, outer breakwater, inner harbor calm water.

Reactions Or Equations

Note

Often simplified as F_wind ≈ 500–1000 N per m³ of wind speed at 50 km/h; scales with V².

Equation

Wind force (drag) = 0.5 × ρ_air × V_wind² × C_d × A_projected

Conditions

ρ_air ≈ 1.225 kg/m³; C_d ≈ 1.0–1.5 for ship superstructure; A_projected ≈ height × length above waterline

Note

Dynamic effect; must be accounted in UKC calculation. Under-keel clearance should include squat margin.

Equation

Squat (additional draft increase) ≈ 0.01 to 0.05 × draft, depending on speed through channel

Conditions

Shallow-draft channels and high-speed transit; ship speed > Froude # 0.25

Section Title

Integrated Airport and Port Design (Comparison Context)

Important Facts

  • Both airports and ports must account for environmental extremes: wind, tide, current, wave, temperature, and precipitation.
  • Philippine context: tropical typhoons and monsoon winds dominate design; seasonal wind pattern is critical for both runway orientation and port shelter.
  • RA 544 encourages private development; engineering standards (ICAO, PIANC, AISC, ACI, NSCP) remain non-negotiable regardless of operator.
  • Runway and channel design both involve correction factors: elevation, temperature, gradient for runways; tide, current, silt for channels.
  • Safety margins essential: UKC for shipping, clear zones for aircraft, freeboard for breakwaters—all prevent catastrophic failure.

Key Definitions

Term

ICAO Annex 14

Example

Philippines adopts ICAO standards via CAAP; mandatory for public airports.

Definition

International Civil Aviation Organization standard for aerodrome design, planning, and operations; governs runway orientation, length, clear zone, taxiways.

Term

PIANC Guidelines

Example

PIANC harbor approach channel widths, turning basin design, and berthing force limits.

Definition

Permanent International Association of Navigation Congresses; provides recommendations for port/harbor design, breakwater stability, and vessel maneuverability.

Term

RA 544 (Build-Operate-Transfer Law)

Example

Clark International Airport, Port of Subic Bay developed under BOT framework; design standards remain ICAO/PIANC/local.

Definition

Philippine law enabling private sector to develop large infrastructure (including ports, airports) under government-approved schemes and regulatory oversight.

Term

Design Storm / Return Period

Example

Runway design typically for 50-year extreme temperature; breakwater for 50–100 year design wave.

Definition

Extreme event (wind, wave, flood) expected once in N years (e.g., 50-year, 100-year storm); used to set design loads for hydraulic structures.

Must Remember

  • Railroad cant formula: e = GV²/(127R). Constant 127 is FIXED. G = 1.435 m (standard gauge). Speed in km/h, radius in m. Result in meters.
  • Runway length corrections are CUMULATIVE (multiply, not add): L_actual = L_basic × (1 + ΔL_elev) × (1 + ΔL_temp) × (1 + ΔL_grade). Elevation = +7% per 300 m; Temperature = +1% per °C ABOVE ISA (not above 15°C flat). ISA at elevation = 15 – 6.5×(elev/1000)°C.
  • Harbor channel depth = Design vessel draft + Under-keel clearance. Depth measured below Lowest Astronomical Tide (LAT), not mean water level. UKC typically 1.0–1.5 m for large vessels.
  • Turning basin: minimum radius = 1.5 × L_ship; preferred = 2.0 × L_ship. Depth = channel depth (no shoaling inside basin).
  • Wind rose determines runway orientation for ≥ 95% wind coverage. Runway heading, NOT runway gradient, is the design driver. Crosswind limit ≈ 10–15 m/s (36–54 km/h) for jets.
  • ISA (International Standard Atmosphere) = 15°C at sea level, decreasing 6.5°C per 1000 m. At 1500 m elev., ISA = 5.25°C. Temperature correction applies ONLY if Airport Reference Temperature (ART) exceeds ISA.
  • Equilibrium cant on railway curves balances centrifugal force at a design speed. If speed exceeds design, insufficient cant → outer rail carries extra load (flange wear, derailment). If speed reduced, equilibrium no longer holds → slight outward swing.
  • Breakwater design: height ≥ design wave height + freeboard + wave setup/runup. Wave setup (η) and runup increase with slope steepness and wave steepness. Design for 50–100 year return storm; overtopping must be <5% allowable per PIANC.
  • Mooring forces: wind (dominant in most climates) + current + wave drift + tide-induced surge. Size bollards, bits, and cleats for total horizontal load divided by line efficiency. Multiple loading cases (wind azimuth, current direction) required.
  • RA 544 (Build-Operate-Transfer Law) enables private sector infrastructure development in Philippines. Engineering design standards (ICAO, PIANC, AISC, ACI, NSCP) remain mandatory regardless of operator/investor.

Last Minute Tips

  • Runway temperature correction is a TRAP: Always calculate ISA = 15 – 6.5×(elev in km) FIRST. Then compare ART (given in problem) to ISA. Correction = +1% per °C OF EXCESS above ISA, NOT above flat 15°C. A hot airport at high elevation may have huge corrections.
  • Cant formula constant 127 is identical for road superelevation AND railway cant, BUT railways must include gauge (G). If G is missing from the problem, assume standard 1.435 m. DO NOT forget gauge—it dramatically changes the answer.
  • Channel depth is below TIDAL DATUM (LAT), not mean water level. If the problem states 'mean high water' or 'mean sea level,' YOU MUST ADJUST. LAT is typically 0.5–1.5 m below MSL in tidal areas.
  • Runway corrections are MULTIPLICATIVE. Many students add them (wrong); write out: L = 2000 × (1.07) × (1.05) × (1.01), not L = 2000 + 140 + 100 + 20. Order: elevation first, temperature second, gradient last.
  • Wind rose orientation for 95% coverage: If the problem shows a wind rose with two nearly equal peaks, the optimal runway heading is the BISECTOR or favors the stronger peak. Do NOT orient perpendicular to dominant wind (that is a classic mistake—you want headwind, not crosswind).

Comparison Tables

Rows

Values

  • e = GV²/(127R)
  • e = V²/(127R) [for vehicles, no gauge factor]

Property

Formula

Values

  • 127 (includes gauge G)
  • 127 (no gauge; implicit in unit conversion)

Property

Constant in formula

Values

  • 100–150 mm (0.1–0.15 m)
  • 100–150 mm (0.1–0.15 m) for high-speed; up to 10% for local roads

Property

Typical e_max

Values

  • Balance centrifugal force on rails; prevent flange climbing
  • Balance centrifugal force on vehicles; prevent side-slip

Property

Purpose

Values

  • Essential on passenger lines; spiral length 0.5–1.0 m/s × V
  • Essential on high-speed roads; spiral length ~0.01V² (m) for 0.6 m/s² jerk

Property

Transition curve

Values

  • Outer rail bears full lateral load; flange wear, derailment risk
  • Vehicle slides outward; skidding, rollover risk

Property

If cant is insufficient

Columns

  • Parameter
  • Railroad
  • Road

Table Title

Railroad Cant vs. Road Superelevation

Rows

Values

  • +7% per 300 m
  • 0–25% (up to 3000 m elev.)
  • Always for elev. > 300 m

Property

Elevation

Values

  • +1% per °C above ISA
  • 0–15% (hot climates)
  • Only if ART > ISA for that elev.

Property

Temperature

Values

  • ~1% per 0.1% slope
  • 0–3% (avg. grade < 1%)
  • For grades > 0.5%

Property

Gradient

Values

  • Elevation → Temperature → Gradient (multiply sequentially)
  • L_actual = L_basic × (1+Δe) × (1+Δt) × (1+Δg)
  • Must follow correct order

Property

Application order

Columns

  • Correction Type
  • Formula / Rule
  • Typical Range
  • When Applied

Table Title

Runway Length Corrections (Cumulative Multipliers)

Rows

Values

  • 3–4
  • 1.0
  • 4.0–5.0

Property

Small general cargo (≤5000 DWT)

Values

  • 13–15
  • 1.5
  • 14.5–16.5

Property

Post-Panamax container (>5000–10000 TEU)

Values

  • 12–13
  • 1.5
  • 13.5–14.5

Property

Panamax container (4500–5000 TEU)

Values

  • 13–14
  • 1.5
  • 14.5–15.5

Property

Large bulk carrier (>50000 DWT)

Values

  • 15–16
  • 2.0
  • 17.0–18.0

Property

Oil tanker (ULCC, >300,000 DWT)

Columns

  • Vessel Class
  • Loaded Draft (m)
  • Under-Keel Clearance (m)
  • Channel Depth Below LAT (m)

Table Title

Harbor Channel Depths (Examples)

Rows

Values

  • Orient runway parallel to prevailing wind
  • ≥ 95%
  • N–S or E–W (matching dominant wind)

Property

Single strong prevailing wind direction

Values

  • Orient runway to bisect or favor stronger direction
  • Often only ≈ 85–90% achievable
  • Compromise heading (e.g., NE–SW)

Property

Two distinct wind maxima (e.g., monsoon + trade)

Values

  • Optimize for terrain/drainage/noise; wind secondary
  • Can be low (≈ 70–80%)
  • Topography-driven (avoid hills, use valleys)

Property

Weak/scattered winds (tropical calm-air region)

Values

  • Single runway at best compromise; may accept lower coverage
  • ≈ 90% acceptable for small airfield
  • Chosen by wind rose; secondary considerations OK

Property

Space constraint (small airfield)

Columns

  • Scenario
  • Action
  • Wind Coverage
  • Typical Runway Heading

Table Title

Wind Coverage & Runway Orientation Decision

Rows

Values

  • Boulders/armor units on sand/gravel core
  • Deep-water (5–30 m); long fetch
  • Permeable; energy dissipation; stable on gentle slopes (1:1.5–1:2)

Property

Rubble-mound (gravity-armor)

Values

  • Hollow concrete/steel box; sand/rock backfill
  • Medium depth (5–15 m); harbor entrance
  • High cost; high strength; impermeable; must prevent undermining

Property

Caisson (cellular)

Values

  • Steel or concrete piles; can be cantilever or braced
  • Shallow water (1–5 m); low-energy sites
  • Quick construction; low material; large bending moments; requires dredging toe

Property

Pile / Sheet-pile

Values

  • Caisson + rubble-mound (hybrid)
  • Variable depth; moderate to high energy
  • Combines advantages; common for major ports

Property

Composite

Columns

  • Type
  • Material / Construction
  • Typical Use
  • Design Considerations

Table Title

Breakwater Types & Design Contexts

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