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The railway structure gauge defines the precise cross-sectional space on every side of and above the track that must remain free of all obstacles. It governs spatial limits for tunnel cross sections, platform edge positions, catenary mast placement, and signalling equipment to ensure safe vehicle passage under all dynamic conditions. This mandatory geometric envelope ensures that no fixed structure or equipment infringes upon the moving vehicle.
The hierarchy strictly separates the vehicle construction outline, the dynamic reference profile, and the infrastructure structure gauge. Heights must be measured perpendicular to the track plane, running through the two rail tops. When assessing stationary conditions with loaded suspension, dynamic allowances are isolated to avoid double counting. Block 14.2 defines infrastructure profiles.
checking the new line gauge first, followed by historical A85, A96, A96T, and AC profiles. A distinct check applies to the train-mounted snowplow profile. Cross-section E and the free pantograph profile must be evaluated here prior to curve overthrow because they do not receive the train body curve overthrow addition. The block concludes with profiles for short overhead structures, single-track tunnels,
circular tunnel boring machines, and double-track tunnels. Block 14.3 examines curve overthrow, which quantifies the horizontal deviation of a vehicle from the track centerline along horizontal curves. Curve overthrow includes center throw inward between the bogies and end throw outward beyond the bogies, incorporating transitions and vertical curvature. On a 500-meter radius, center throw equals 81 millimeters and end throw equals 63 millimeters.
New line combined widening remains strictly distinct from the conditional station case. Immediately following, Block 14.4 mandates track level and trackside clearances for flangeways, track snow scrapers, shunting staff safety, future track adjustment, building door openings, and loading equipment. Block 14.5 establishes the fouling point, defining the exact location where adjacent track envelopes no longer overlap. The standard base calculation sums
2120,1700, and 100 to equal 3920 millimeters. This baseline must be established before evaluating both independent track radii for localized curve and cant additions. Block 14.6 examines transport and vehicle profiles, which dictate how specific loading units integrate with rolling stock. General vehicle codes such as G1, GA, GB, GC, NO1, and NO2 do not automatically confer blanket route permission.
Transport coding requires precise addition. Under the P407 combined transport code, the 4,070mm loading unit is added to the 330mm wagon carrying level, yielding a 4,400mm total height, above the top of the rail. The 330mm dimension strictly represents the wagon carrying level, not a passenger platform or universal platform addition. Block 14.7 details the horizontal space requirements for dynamic vehicle movement.
Horizontal calculations incorporate primary and secondary suspension play, wheel rail play, bogie play, the roll center, cant, and the actual vehicle cross-section. The resulting displacement allowance is strictly added to the vehicle half-width. It is never evaluated as the full half-width on its own. Positive part mathematical terms in these formulas cannot be converted into negative deductions. Block 14.8 governs passenger
-platform interfaces. Platform calculation begins first with circular curve, partial curve, and turnout geometry, followed by cant and cant ramps with offsets and heights. In the worked case, featuring a 500-meter radius, 100-millimeter cant, and 760-millimeter height, Illustrative first edge case results yield an inside horizontal coordinate of
1,811.7 millimeters and a vertical height of 692.6 millimeters. The outside horizontal coordinate is 1718.0 millimeters with a vertical height of 926.2 millimeters. The alternative inclined edge necessitates a different mathematical expression. Door locations and boarding gaps are evaluated subsequently. The technical specification for interoperability regarding persons with reduced mobility
mandates a maximum 75mm horizontal gap and 50mm vertical gap, with no internal step. This defines strict level access. It does not represent universal permitted gaps for all standard boarding designs. Block 14.9 specifies vertical space requirements. Allowances must account for sag and hump vertical curve overthrow, upper and lower points, primary and secondary suspension deflection, and wear. During unequal wheel wear and
deformation checks, the radius loss equates to exactly half the diameter loss. A mandatory procedural requirement within Block 14.9 dictates that vehicle route compatibility must be established across the entire intended route before committing to any vehicle design or procurement order. Block 14.10 defines the strict verification procedures required to confirm structural clearances on physical infrastructure. Permitted verification methods
include physical loading templates, route laser surveys, and passing load structure profile monitors. Traceable governing locations are mandatory, to account for uncertainty. Software simulations compute kinematic envelopes, but do not independently constitute formal route authorization. Block 14.11 addresses constraints and infrastructure enlargement. Following any physical alteration, the location requires immediate and complete rechecking.
Block 14.12 provides the final summary of structural gauging requirements, consolidating the preceding rules. Assessors must match specific profiles with their exact calculation rules, always apply local track geometry, and base checks on the actual vehicle and load case. Traceable whole route verification is mandatory. Finally, electrical clearance checks and
boarding accessibility checks must remain completely separate.