Requirements and test methods of strength for the superstructure of bus
1 Scope
This standard specifies the technical requirements and test methods of strength for the superstructure of bus.
This standard is applicable to Classes B, II and III buses and special school buses of Categories M2 and M3, and may be referenced by other buses of Categories M2 and M3.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB 11551 The protection of the occupant in the event of a frontal collision for passenger car
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
group of vehicle types
those vehicle types, proposed in future as well as existing now, which are covered by the approval of the worst case, in respect of this standard
3.2
worst case
vehicle type, among a group of vehicle types, least likely to withstand the requirements of this standard in respect of the strength of superstructure. The three parameters which define the worst case are: structural strength, reference energy and the residual space
3.3
double-deck bus
vehicle with at least a part of passenger space arranged on upper and lower decks and no standing passenger space on the upper deck
3.4
passenger compartment
space intended for passengers' use excluding any space occupied by fixed appliances such as bars, kitchenettes or toilets
Note: It is revised from Definition 3.22 in GB/T 4780-2000.
3.5
occupant restraint
any device which connects a passenger, driver or crew member to his seat and reduces their injuries by limiting the movement of the wearer's body during a rollover
3.6
vertical longitudinal central plane
VLCP
vertical plane which passes through the mid-points of the front axle track and the rear axle track
3.7
residual space
space to be preserved in the passengers', driver's compartment(s) and separate compartment to provide better survival possibility for passengers, driver and crew in case of a rollover accident
