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4. Advanced Structural Calculations
Structural calculations for super high-rises buildings higher than 60 m
Time history response analysis the method of structural calculation
where changes in force and deformation occurring to the building by seismic waves of a major earthquake are continuously simulated by the
computer to verify seismic resistance of the building
Since very advanced technical capability is required to properly judge
the appropriateness of the calculation result, the result is evaluated by specialists of university professor level at an independent specialized
organization designated performance evaluation organization and the Minister of Land, Infrastructure and Transport will make final judgment
for certification based on the evaluated result.
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5. Specification Regulations
{ Durability of the foundation and members
specifications common for all types of structures: This specification should be complied with whether or not the structural
calculation is required.
{ Specification regulations for each type of structure wooden, masonry, steel, RC, SRC,
etc.: This may be omitted when calculation of ultimate bearing capacity or time history response analysis is conducted.
[Example of Specification Regulation] Common
Where corrosion or decay is particularly likely at parts important in terms of structural strength,
materials resistant to corrosion or decay, or those treated with effective rust-preventatives or corrosion-preventatives, should be used.
Wooden structure
The size of the column should be 13.5 cm per side or more on the first floor of a two-story building.
Corner pillars of a building of two or more stories should be through-pillars.
Effective corrosion-preventive treatment should be provided to the foundation and columns less than 1 m in height from the ground.
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Pr in ciple of Fir e pr oof a n d Eva cu a t ion Re gu la t ion s
To be specific, measures should be taken based on the following principles:
1 Prevention of the spread of fire from a neighboring building 2 For buildings highly prone to fire, prevention of fire from occurring indoors,
spreading, or causing the collapse of the building 3 In the event of a fire, ensure the evacuation and safety of users, and facilitate
fire-fighting activities
Principle Safety measures against fire should be taken to buildings based on past
fire cases and the experience of the fire-related regulations, in order to protect people’s lives and assets against fire.
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A fireproof building
is a building most unlikely to catch fire from outside or to collapse by ordinary fire.
A building that falls under any of the following descriptions and has fire-prevention equipment at any opening likely to catch fire from outside:
a. Major structural parts wall, column, floor, beam, roof, stairs are fireproof
specification regulation. b. Major structural parts are proven, by the
fireproof performance verification method performance regulation, to
withstand a fire until the fire ends. c. Major structural parts are
certified by the Minister of Land, Infrastructure and Transport to be able to withstand a fire until
it ends performance regulation. Fire-prevention equipment is equipment which prevents fire, such as fire doors with
fire-shielding performance capable
of shielding fire for 20 minutes or drenchers water curtain equipment, which are certified by the Minister of MLIT for compliance with the notified regulations.
A semi-fireproof building
is a building less likely to catch fire from outside and collapse by fire inside, having performance in line with the fireproof building and falling under either of the following:
1 Major structural parts are semi-fireproof; 2 External walls are fireproof;
3 Noncombustible materials, such as steel, are used for frames.
What is a “fireproof” and “semi-fireproof” building?
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Fireproof structure
Fireproof performance
:
Structure of reinforced concrete, steel, etc.
, in case of an ordinary fire, capable of preventing the collapse or spread of the fire until it ends. A structure is
qualified to be fireproof by either satisfying the requirements given in the Ministerial Notification or being certified by the
Minister of MLIT.
Semi-fireproof structure
Semi-fireproof performance
:
Structure of wood, etc.
having performance to control the spread of an ordinary fire. A
structure is qualified to be semi-fireproof either by satisfying the requirements
given in the Ministerial Notification or being certified by the Minister of MLIT.
Fireproof and Semi-fireproof Structures
Reinforced concrete structure
Plaster board: double panels 12
mm + 9 mm both sides
Column and wall
Column
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Noncombustible, quasi-noncombustible, flame-retarding materials
[Requirements] 1
Does not combust. 2
Does not suffer deformation, fusion, cracking, or other damage that is harmful in terms of fire prevention.
3 Does not generate smoke or gas, toxic or harmful
enough to prevent evacuation.
Materials satisfying
all the requirements below
during the
time range shown in the right
when subjected to heat.
This qualification is granted either by certification by the Minister of LIT or
compliance with the stipulations set by the Minister of LIT.
5 m in . 1 0 m in .
2 0 m in .
Duration
Fla m e - r e t a r din g plyw ood, e t c.
Fla m e - r e t a r din g
Sa w du st - m ix e d ce m e n t boa r d,
pla st e r boa r d, e t c.
Qu a si- n on com bu st ibl
e
Con cr e t e , st e e l pla t e , e t c.
N on com bu st ibl e
Exam ple Material
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6. Means of Evacuation