ASME RT-2:2021 pdf download

ASME RT-2:2021 pdf download Safety Standard for Structural Requirements for Heavy Rail Transit Vehicles
train: one or more vehicles coupled together.
ultimate strength: the maximum load-carrying capabilityof a structure, for a load applied at a specified location anddirection. For further deformation of the structure, theload capable of being supported will be less than thismaximum load.
vehicle: see heavy rail transit vehicle.vehicle vertical loads:
(a) ready-to-run load: the weight of a vehicle that isservice ready with all mounted components,includingfull operating reserves of lubricants, windshield fluid,etc., but without any crew or passenger load.
(b) seated load: ready-to-run load plus the crew and allpassenger seats occupied with average weight per personof 79.5 kg ( 175 lb).
(c) carbody volume capacity load: a seated load plus allavailable standee areas occupied with a standee densitythat results in a floor pressure of 488.4 kg/m2 ( 100 lb/nt25.NOTE:An alternate occupant weight based upon specific serviceconditions, such as service to airports and use of luggage racks,may be specified.
yield strength: the stress published by American Societyfor Testing and Materials (ASTM) for the specified mate-rial and grade. If the material used is not covered by anASTM specification,or another specification,theminimum yield strength for design shail be as guaranteedby the material supplier.
3 INTEROPERABILITY
This section covers geometric compatibility considera-tions for collisions between vehicles of different designoperating on the same routes of the subject transit system.3.1 Anticlimber and Coupler Interface
Each heavy rail transit vehicle shall incorporate an anti-climber at each end of the vehicle.The height and design ofthe anticlimber and coupler on new heavy rail transit vehi-cles shall be compatible with existing heavy rail transitvehicles that are operated on the same routes of thesubject transit system. The anticlimber shall be designedfor engagement between vehicles to mitigate override ortelescoping in a collision, including any condition of failedor deflated suspension elements. In the event of a collisionwith another rail vehicle, the coupler system shall includea feature that will permit engagement of anticlimbers.Seesection 6 for additional requirements. Design of thevehicle leading end structure shall not interfere withproper engagement or operation of the vehicle anticli-mber system. Geometric compatibility does notmandate coupling between vehicles of different designs.
3.2 Multiple Unit Operation
All combinations of vehicles to be operated within atrain shall be considered in assessing the effect of multipleunit operation in a collision.
4 STRUCTURAL REQUIREMENTS
The carbody shall withstand the maximum loads consis-tent with the operational requirements and achieve therequired service life under normal operating conditions.The carbody and vehicle design shall be based on thedesign load requirements specified in section 5.Thecapability of the structure to meet these requirementsshall be demonstrated by calculation and/or appropriateproof of design testing.
The strength of connections between structuralmembers for all structural loading requirements outlinedin Table 4-1 shall exceed the ultimate load-carrying capac-ity of the weakest member joined. For these load cases,theultimate load-carrying capacity is defined by applying theload at the location and in the direction specified in Table4-1 but increased in magnitude to the maximum load thatcan be resisted by the structure, as determined by obser-ving that further increase in deflections will result in adecrease in the load capable of being carried by the struc-ture. References to sheathing in Table 4-1 refer only tostructurally related (load-carrying) sheathing.
4.1 Welding
Design of welded structures shall be in accordance withAwS D15.1,AwS D1.1/D1.1M for steel, and AwS D1.2/D1.2M for aluminum or equivalent.
4.2 Articulation
An articulation, if used, shall include structure to meetthe requirements of section 5.
4.3 Design Parameter Tolerance
The allowable stresses for the loads specified insection 5 shall consider the limiting cases of dimensionaltolerances, manufacturing processes,workmanship, andother manufacturing effects.
4.4 Demonstration of Strength and Structural
Stability
lt shall be demonstrated by analysis (section 9) and/ortests (section 10) that the requirements of section 5 areachieved.
4.5 Truck to Carbody Attachment
A mechanism for attaching the completely assembledtruck,including the bolster if used,to the carbodyshall be provided, with strength levels in accordancewith section 5.The trucks shall remain attached to the