Notice on Printing and Distributing the "Strengthened Technical Requirements for Civil Buildings with a Building Height of Over 250 Meters (Trial)"

The public security fire brigades of provinces, autonomous regions, and municipalities directly under the Central Government, and the Fire Bureau of the Public Security Bureau of the Xinjiang Production and Construction Corps:

In order to protect the fire safety building level of the civil building with a height of more than 250 meters and improve its fire resistance capacity, the Bureau organized the “Technical Requirements for Strengthening the Fire Protection Design of Civil Buildings with a Building Height of Greater Than 250 Meters (Trial)” (see Attachment, hereinafter referred to). "The "Strengthening Technical Requirements"" is now being issued to you. Please implement it conscientiously and implement the following requirements:

First, strengthen territorial management. As of the issuance of this circular, more stringent fire prevention measures for construction projects with a building height of more than 250 meters will be reviewed and determined by experts organized by the corps.

Second, strict expert review. Each of the corps should implement the “Strengthening Technical Requirements” and combine local fire fighting and rescue capabilities with respect to fire resistance, external plane layout, internal plane layout, safety evacuation and evacuation, fire protection structure, building insulation and external wall decoration of building components. Extensive technical review of fire protection performance, automatic fire-fighting facilities and fire fighting and rescue installations as well as their reliability, firefighting water supply, fire-fighting power and distribution, and electrical fire protection of building construction, to ensure that more stringent fire prevention measures are implemented Enhance self-defense and self-rescue capability in fires of high-rise buildings. Expert review opinions shall be clear and specific, and no principled opinions that are ambiguous, can not be implemented or need to be explained otherwise, shall not be adopted in any modification to circumvent the implementation of the current state technical standards for fire engineering construction, and it is strictly forbidden to replace or reduce the national standards required by administrative measures. Fire protection measures.

Before the release of this notice, the civil building fire protection design with a building height of over 250 meters has been accepted by the public security agency's fire protection agency, and expert evaluation opinions have been formed according to the procedure. The review may be conducted according to the contents of the expert review comments, but the construction unit should be encouraged. Actively follow the "enhanced technical requirements" to modify the original fire design program.

Ministry of Public Security Fire Department

April 10, 2018

Technical requirements for strengthening the fire protection design of civil buildings with a building height greater than 250m (for trial implementation)

Article 1 This technical requirement applies to the fire protection design of high-rise main parts (including the basement within the main projection range) of civil buildings with a building height of more than 250m. The fire protection design of the podium shall comply with the provisions of the current national standard "Code for the Fire Protection of Architectural Design" GB 50016.

Article description

Article 1 High-rise buildings are generally composed of high-level main parts and their attached multi-storey podium parts. This technical requirement is mainly aimed at the fire protection design of high-rise buildings in civil buildings and the basement part in the projection range. The podium may not perform this technical requirement, but it shall implement the current national standard "Code for the Fire Protection of Architectural Design" GB 50016. When the annex building is a high-rise building, the fire protection design of the subsidiary building shall also comply with this technical requirement.

This technical requirement is a strengthening requirement based on the relevant provisions of the current national standards. For other fire protection requirements that are not covered by this technical requirement, relevant provisions of the current national standards must still be implemented.

Article 2 The fire-resistance limit of building components shall comply with the following provisions in addition to the current national standard "Code for the Fire Protection of Building Design" GB 50016.

1 The fire resistance limit of trusses with load-bearing columns (including diagonal braces), conversion beams, and structural reinforcements should not be lower than 4.00h;

2 The fire-resistance limit of components with similar functions of beams and beams shall not be lower than 3.00h;

The fire resistance limit of the 3rd floor and roof load-bearing components should not be lower than 2.50h;

4 The fireproof limit of the outer wall of the core barrel should not be lower than 3.00h;

5 The fire-resistance limit of shaft walls such as cable wells and pipeline wells should not be less than 2.00h;

The fire-resistance limit of the 6-room partition wall shall not be less than 1.50h, and the fire-resistance limit of partition walls on both sides of the evacuation aisle shall not be less than 2.00h;

7 When the load-bearing steel structure in the building is protected by fire-retardant coatings, a thick-coated steel structure fire retardant coating shall be used.

Article description

The second civil building with a building height of more than 250m is prone to burn for a long time in the event of a fire and is difficult to extinguish. The main load-bearing components must have high fire resistance; the integrity of shafts such as cable wells and pipeline wells is damaged. It will cause the fire to spread rapidly inside the building and become difficult to control. In order to further improve the building's fire safety and evacuation and rescue safety, through the investigation of Shanghai Center Building, Wuhan Minsheng Bank Building and other domestic high-rise building cases, comprehensive consideration of fire safety requirements, existing technical conditions, and economic rationality of ultra-high-rise buildings, etc. The current national standards are based on the fire-resistance requirements for civil building components, and reference is made to the United States' NFPA220 and other standards for the type of building structure, which improves the fire-resistance requirements of several building components.

(1) Load-bearing columns (including diagonal braces), beams, core tubes, etc. are important components of the super high-rise building system, and the conditions of stress are more severe. If such components are damaged or failed under fire conditions, they will seriously affect the construction. The overall stability. Therefore, the fire-resistance limit of the load-bearing columns (including braces) was increased to 4.00 h, and the fire-resistance of the beams, the components with similar functions to the beam structure, and the peripheral wall of the core barrel was raised to 3.00 h. The fire resistance of the load-bearing components of the floor and roof was improved. The limit increases to 2.50h. As the transition beam and structural reinforcement truss are key components of the super high-rise building, its role is equivalent to that of the load-bearing column. After the components such as the conversion beam fail, the supporting columns connected to it will also fail. Therefore, it is required that the transition beam, the structural reinforcement truss, and the bearing pillars have the same fire resistance limit.

(2) The peripheral wall of a building core tube refers to a partition wall at the junction with the circular evacuation walkway or other non-core tube space.

(3) A large number of shafts, such as elevator shafts and pipeline wells, are installed in the core barrel of a super high-rise building. These shafts can easily become a passage for fire and smoke to spread vertically. The fire-resistant limit of the shaft wall is increased to 2.00h to prevent fire from spreading through these shafts to the outside of the core barrel.

(4) Improving the fire-resistance limit of fire partition walls, such as partition walls and evacuation walkways, can provide a safer evacuation environment for personnel.

(5) Steel structures in high-rise buildings are mainly used in load-bearing structures such as load-bearing columns and beams, which have higher fire-resistance limits. The use of thick-coated steel structure fire-retardant coatings for fire protection is beneficial to improve the fire resistance of components. Thick-coated steel structure fire retardant coating technology is mature, high reliability, has been widely used in Haikou Twin Towers, Wuhan Minsheng Bank Building and many other projects.

Article 3 The fire separation shall meet the following requirements:

1 Circular evacuation walkways should be installed around the core of the building, and doors and windows on the partition walls should be Class B fire doors and windows;

2 elevators in the building should be set up waiting hall;

3 The foyer (public lobby) used to expand the front room shall be separated from the surrounding communicating space by a fireproof partition with a fire-resistance limit of not less than 3.00h. Class A fire doors and windows shall be used for doors and windows that communicate with the hall (public lobby);

4 The kitchen shall be separated from the adjacent area by fireproof partitions and Class A fire doors with a fire endurance of not less than 3.00h;

(5) Class A fire doors shall be used for the front room of stairways and stairwells, Class B fire doors shall be used for the doors of hotel rooms, and class A fire doors shall be used for inspection doors on the shaft walls of cable and pipeline wells;

6Firewalls and fire walls shall not be replaced by fireproof glass walls or fire shutters.

Article description

Article 3 This Article further clarifies the requirements for the separation of cores, elevator halls, entrance halls (public halls), kitchens, smoke-proof stairwells of super high-rise buildings, in particular, the fire protection requirements for doors and windows on walls and firewalls and fireproof partitions. The practice has been strengthened.

(1) Core tube

The core of a super high-rise building usually contains functions such as evacuation stairs, elevator shafts, ventilation shafts, cable wells, toilets, and equipment rooms. Enhancing the fire separation of the core cylinder plays an important role in preventing the fire from spreading vertically inside the building and ensuring the safety of evacuation and external rescue. An annular evacuation aisle is arranged around the core barrel to better separate the areas with large fire hazards on the floor from the core barrel, avoiding the direct connection between these areas and the core tube, and the safety exit cannot be used in case of fire. Such issues will help further improve the building's fire safety performance.

(2) elevator hall

The elevator shaft in the building is likely to become a passage for the spread of fire along the vertical direction in the event of a fire. Therefore, a hall must be installed to avoid placing the elevator directly in the functional space.

(3) Foyer (public lobby)

The foyer of the high-rise building (public lobby) is the main area for the distribution of personnel within the building. Most of the building's evacuation stairs, fire elevators, and auxiliary evacuation elevators need to use the lobby (public lobby) as an enlarged front room to access the outside. Therefore, not only should the fire load of the site be strictly controlled, but also fire separation measures should be taken to reduce the impact of fire in other areas on the lobby (public lobby).

(4) Kitchen

The kitchen fire risk is relatively large, and the fire protection separation of the kitchen further increases the corresponding requirements on the basis of the fireproof partitions and Class B fireproof doors with fire resistance limits of not less than 2.00h as prescribed in the current national standards.

(5) Smoke prevention stairwells, shafts, etc.

The current code requires the use of Class B fire doors for smokeproof stairwells and front room doors, and class C fire doors for inspection doors on shaft walls such as cable wells. This section integrates Changsha International Riverside Finance Center, Jiujiang International Finance Plaza A1# Building, Wuhan Changjiang Shipping Center Project 1# Tower and other engineering practices to increase the building height above 250m into the front door and shaft of smokeproof stairwells. The uniform inspection door requires Class A fire doors to further reduce the risk of fire spreading vertically inside the building.

In combination with Wuhan Center and other engineering practices, it is required to use Class B fire doors in the doors of hotel rooms to control the fire in the rooms and reduce the hazard and impact of fire spread.

(6) Fireproof glass wall, fire shutter

The reliability of fireproof glass walls is not only related to the fire resistance of the glass itself, but also depends on the installation of the fixed frame. For the C fireproof glass, it also depends on whether the cooling water protection system is well maintained, the water source is reliable and can be normal Working conditions and other conditions. Therefore, this article states that firewalls and fire walls in buildings cannot be replaced with fireproof glass walls to improve the effectiveness and reliability of fire separation.

In actual use of the fire shutter, there are problems such as poor anti-smoke effect and low reliability. Therefore, for high-rise buildings, firewalls and fire walls should not be replaced by fire shutters.

Article 4 The hotel's clothes well openings are strictly prohibited to be installed in stairwells. They shall be installed in separate service rooms. The service room shall be separated from other areas by fireproof walls with a fire-resistance limit of not less than 2.00h. Room doors shall be used. Class A fire door.

Dirty clothes wells should meet the following requirements:

1 At the top, the sprinklers and fire detectors of the automatic sprinkler system and the smoke outlet associated with the automatic fire alarm system should be installed;

(2) Sprinklers for an automatic sprinkler system should be installed at least once every second;

3 Class A fire doors should be used for access doors;

4 Contamination lanes should be made of non-combustible materials.

Article description

Article 4 The stained well is generally a stainless steel cylinder. The sewage clothing is put into each floor opening and sent to the bottom outlet through the gravity to the storage room or the laundry room. The current national standards require that the shafts in the building should be fire-rated on each floor. However, the sewage well is a well that runs completely from bottom to top. It is connected to the layers through the door where the clothes enter the door. It cannot be separated layer by layer due to the need of the function. Therefore, measures should be taken to prevent the fire from spreading vertically through the clothes well. In addition, the sewage well is a concealed space. According to its structure and the characteristics of smoke propagation, fire detectors and smoke exhaust ports need to be installed in the upper part of the clothes well in order to detect the fire in an early stage and remove the smoke as soon as possible.

Article 5 Inflammable materials shall not be arranged in the foyer (public lobby) used for expanding the front room. The decoration materials of the ceiling, wall surface and ground shall be made of non-combustible materials.

Non-combustible materials shall be used for the external decoration of buildings and billboards, etc. It shall not affect the escape of fire, fire-fighting and rescue, and natural smoke emission in the room, and shall not change or destroy the fire-protection structure of the building facade.

Article description

Article 5 Decorations, billboards, etc. on the external walls of a building, in the event of a fire, will easily lead to the spread of fire along the building facade. Therefore, non-combustible materials should be used. At the same time, the decoration and billboards should not cover the exterior windows of the building so as to facilitate the building smoke exhaust, fire escape, and external fire extinguishing.

Article 6 In addition to the construction of radio and television transmission towers, the safety evacuation facilities in the high-rise building shall meet the following requirements:

1 The evacuation stairs should not use scissors stairs;

2 The setting of evacuation stairs shall ensure that when any of the evacuation stairs cannot be used, the total net width of other evacuation stairs can still meet the need for safe evacuation of all personnel on each floor;

3 The number of evacuation stairs in the fire protection zone with a building area greater than 2000m2 in the same floor shall not be less than 3, and each fire prevention zone shall have at least one independent evacuation staircase;

4 Evacuation stairwells shall be provided on the first floor with a direct access to the outside. When it is really necessary to use the first floor foyer (public lobby) as an extension of the front room to the outside, the evacuation distance should not exceed 30m.

Article description

Article 6 The higher the height of the building is, the longer the evacuation distance will be, and the more people will enter the stairwell, resulting in crowded people in the stairwell and long evacuation time. According to American evacuation drills on some high-rise buildings and people's evacuation behavior and time in fire incidents, for normal adults, when the density of people in the stairwell is 2 persons/m2, the speed of walking down is 0.5. m/s; When 4 people/m2, the walking speed will be 0. Therefore, the increase in the width and number of evacuation stairs will greatly shorten the evacuation time of personnel, but in reality, the number and width of evacuation stairs are also constrained by various factors. This article makes this provision on the basis of comprehensive consideration of various factors.

For the evacuation of super high-rise buildings, various countries have made relatively strict regulations, such as the United States "International Building Code" (2015 version) stipulates that "super high-rise buildings with a building height greater than 128m should be based on the number of evacuation stairs prescribed in the code. Add an evacuation stair, which should not be a scissors stair." Another example is the British "Building Ordinance 2010 - Fire Safety - Approval Document B-volume 2" (2013 version) provides that buildings with a building height of more than 45m, to take measures to strengthen the design to ensure the safety of evacuation, such as considering an evacuation When the stairs are not available, the remaining evacuation stairs can still meet the requirements for evacuation of all personnel.

The scissors stairwell is the same position where the two stairs are stacked in the building. Under the conditions of the same total evacuation width and bench width, the dispersion of the non-scissors stairwell is obviously better than the scissors stairwell, more in line with the current country. The standards concerning the basic principles for the decentralization of safety exits must be established. Therefore, this code specifies that scissors are not allowed in super high-rise buildings to ensure that people on the floor have evacuation routes in at least two directions in case of fire.

Since China's regulations currently do not specify the use of personnel density values for various uses, it is difficult to design a unified number of evacuation, so the provisions for the increase of evacuation stairs are based on the floor area of fire prevention partitions.

The evacuation stairwells of high-rise buildings are usually set inside the core barrels. In the first floor, they often cannot lead directly to the outside, and they need to go outdoors through the foyer or public lobby. The lobby and the public lobby meet the third article