外文翻译---公寓建筑物的防火安全设计-建筑结构(编辑修改稿)

外文翻译---公寓建筑物的防火安全设计-建筑结构(编辑修改稿)内容摘要：

m high, in many cases to meet travel distances specified by the BCA, two stairs will be necessary. The minimum number of exits, in the Acceptable Solutions to the NZBC (BIA, 1991), are based on the number of beds (ie the occupant load) in the apartment building. For apartments with less than 100 beds two exits are required. For apartments with over 100 beds two exits are required, plus an additional exit for every 100 beds or part thereof greater than 100. The objective of two stairs is to provide an alternative means of egress if one exit is blocked. Having multiple stair shafts can also reduce egress distances and allow occupants to change egress routes depending on the conditions. The three main factors building codes use to determine if two or more stairs are required, are the number of occupants, the number of floors and the characteristics of the occupants. Some of the additional areas that should be considered in determining the stair requirements are: Fire brigade utilisation and rescue operations Sprinkler protection Fire resistance rating of exit paths Smoke control systems in the exit paths Emergency plan To determine the relative effectiveness of a single stair, Hagiwara et al (1997) have proposed a probabilistic model based on the expected number of occupants unable to XX建筑大学毕业设计外文文献及翻译 9 escape. The model provides a basis for evaluating a single stair against the building code based on: The probability of a fire occurrence in the room The probability the fire develops into a hazardous fire The probability the door is left open The efficiency of rescue by the fire brigade The degree of protection of the escape route Single stair buildings are permitted in the UK provided certain conditions are met. Clause of Approved Document B (Department of the Environment, Transport and the Regions, 2020) states: Every dwelling should have access to alternative escape routes so that a person confronted by the effects of an outbreak of fire in another dwelling can turn away from it and make safe escape. However, a single escape route from dwelling entrance door is acceptable if either: (a) the dwelling is separated from the mon stair and: (i) every dwelling is separated from the mon stair by a protected lobby or mon corridor (see diagram 12), and (ii) the travel distance limitations in Table, on escape in one direction only, are observed。 Effectively, this means that the required number of stairs is not a function of the building height, provided travel distances and other building requirements are met. Therefore, it is possible to have tall single stair apartment buildings. Figure 2 shows the maximum travel distances and stair requirements of Approved Document B (Department of the Environment, Transport and the Regions, 2020). Some of the important requirements for single stair buildings is the provision of openable vents and/or automatic opening vents in the stairs and the corridors. These vents provide a means of venting the stairs of smoke, for both occupants and fire brigade. XX建筑大学毕业设计外文文献及翻译 10 Refuge Floors and Areas Refuge floors and areas provide rest locations for escaping occupants, a safe area for both disabled and ablebodied occupants and a staging area for the fire brigade. The BCA and the Acceptable Solutions to the NZBC do not prescribe refuge floors, however they are prescribed in the Hong Kong building code (Lo and Will, 1997). In a fire engineered apartment building refuge floors may be justifiable if the building was an ultra highrise building, with excessive travel distance via stairs. Refuge areas are more monly used in Australia and New Zealand to provide safe areas for disabled occupants. In apartment buildings a mon emergency strategy is for disabled occupants is to remain in their apartments until assistance arrives. Refuge floors The Building Code of Australia and the Acceptable Solutions to the NZBC do not specify refuge floors for apartment buildings. However, they are prescriptive requirements for highrise buildings in the Hong Kong Code of Practice (Lo and Will, 1997). The functions of refuge floors (Lo and Will, 1997) are to: Act as a relief area for the evacuees in a fire situation Act as a subbase for fire fighting purposes XX建筑大学毕业设计外文文献及翻译 11 Act as a mand point for the rescue personnel to assist the evacuation of the building Provide a place for disabled or partially disabled occupants to wait for assistance before being evacuated Allow occupants to move to an alternative staircase Allow smoke separation at the refuge level in the stair case Lo and Will (1997) also state that refuge floors can psychologically assist occupants under escape conditions. Refuge floors can psychologically relieve occupants by: Reassuring them that the height of escape is not too onerous Providing an area for cognitive and decision control Seeing the presence of fire brigade personnel Refuge floors can also be used as a safe area where lifts are controlled and coordinated for egress. Passenger lifts not used on the fire floor can be used at the refuge floor to evacuate occupants (Lo and Will, 1997). Highrise buildings are usually broken up into lowrise, midrise and highrise sections, with lifts that serve each section separately. To assist in rescue operations, lifts that do not serve the fire floor can be used for rescue and mobilisation of fire brigade personnel and equipment. The arguments against refuge floors (Lo and Will, 1997) are that: They provide an additional cost to the building owner in terms of building cost and nonutilised space It can be difficult to maintain and enforce the use of refuge floors There are already protected escape routes Unless people have difficulty in escaping they are unlikely t。