JP5506045B2 - Evacuation start time calculation method - Google Patents

Description

  The present invention relates to a method for calculating an evacuation start time until a occupant in the room starts evacuation when a fire occurs in the room in the building.

  When designing a building that does not comply with the Building Standards Act specifications, such as building smoke evacuation equipment and fire shutters, check the safety through evacuation safety verification and check the “performance evaluation document” of the evaluation organization and the “Minister of the MLIT” Acquire a certificate. The evacuation safety verification at this time consists of room evacuation, floor evacuation, and whole building evacuation as described below.

Residential evacuation: Until people in the room evacuate to the corridor, they should not be affected by the smoke drop.
Floor evacuation: Until everyone on the floor evacuates into the staircase, it should not be affected by smoke drops.
Whole building evacuation: The evacuation route until the residents evacuate to the ground should not be affected by smoke.

  Among these, as an evaluation method for living room evacuation, it is confirmed that the evacuation time is below the limit smoke layer descent time as follows. This evacuation time is the evacuation start time until the occupant in the room notices the fire and starts evacuation when a fire occurs in the room in the building, and from the start of evacuation until moving outside the room The evacuation action time further includes an in-room walking time when the occupant walks in the room and an exit passage time when passing through the exit.

Evacuation time = Evacuation start time + Evacuation action time = Evacuation start time + Living room walking time + Exit passage time ≤ Limit smoke layer descent time

As the evacuation start time, for example, the following formula 2 is often used. In addition to this, a method of adding 180 seconds to the calculation formula of Formula 2, a method of calculating the time point when smoke falls to a height of 10% under the ceiling, and a calculation method of Patent Document 1 are also proposed. .
(Formula 2)
t _start : Evacuation start time (s)
A: Living room floor area (m ² )

Further, as the walking time, the following formula 3 is often used.
(Formula 3)
t _travel : Walking time in the room (s)
L: Walking distance (m)
v: Walking speed (m / s) <general office 1.3m / s, general 1.0m / s>

In addition, the following formula 4 is often used as the exit passage time.
(Formula 4)
t _queue : Exit passage time (s)
p: Population density (person / m ² )
A: Living room floor area (m ² )
N: Effective flow coefficient (person / m · s) <Generally 1.5 person / m · s>,
B _eff : Effective door width (m)

Therefore, the evacuation time is generally expressed by the following equation (5).
(Formula 5)

On the other hand, as the limit smoke layer descent time, the following formula 6 is often used. This formula is also called Tanaka's simple smoke drop method, where smoke accumulates from the ceiling in the living room and smoke falls from the floor to a certain smoke layer height (generally 1.8m) as the limit time for evacuation. To do.
(Formula 6)
t _s : smoke layer fall time (s)
ρ _s : smoke layer density (kg / m ³ ) <generally regarded as initial fire and often set at 1.0 kg / m ³ >
A _R: room floor area (m ²⁾
k: Coefficient related to the amount of fire plume (-) <generally 0.08>]
Q ₀ : Fire growth rate (kW / s ² ) <Depending on room usage. In general, office room 0.102, meeting room 0.016, etc.>
Z: Smoke layer height (m)
H _R : Ceiling height (m)

JP 2010-33361 A

  By the way, when a design change of a living room occurs in a building where evacuation safety verification has been acquired by the Minister's certification, the performance evaluation and the Minister's certification must be repeated for each change. Since these applications take months, it is necessary to decide the layout plan of the tenant room several months before the pre-construction inspection, but in reality it is not decided so quickly. This is a problem in determining the layout plan.

  If a child room with a partition up to the ceiling is formed in the room of the building, it is impossible to grasp the situation of fire from the child room in the part of the room other than the child room (called the parent room), or L-type or It is said that it is necessary to carry out verification considering the delay of evacuation because the view is not good in bent-shaped rooms such as U-shaped and B-shaped, and the evacuation start is delayed for people far from the fire point.

  For this reason, conventionally, the smoke detector alarm time for the child room, the time to check from the child room to the parent room are calculated for each plan, the partition wall of the child room is made of glass, A method has been adopted in which the upper part is made into a slit and smoke in the parent room is drawn into the child room so that it can be noticed quickly. There were drawbacks such as being unable to enter, and the restrictions on partitioning specifications were large.

  The present invention has been made in view of the above-described problems, and it is an object of the present invention to provide an evacuation start time calculation method that can easily calculate a safe evacuation start time regardless of a layout plan in a room of a building. It is what.

In order to achieve the above object, the present invention provides a method for calculating an evacuation start time t _st until a occupant in a room starts evacuation when a fire occurs in the room of the building, The start time t _st (s) is the smoke layer density ρ _s (kg / m ³ ), the floor area A _R (m ² ) of the whole room, the coefficient k related to the amount of fire plume, and the fire growth rate Q ₀ (kW / s ² ) A method for calculating the evacuation start time, which is calculated by the following formula 1 using a ceiling height H _R (m) and a coefficient φ of 0.95 or less.
(Formula 1)

  According to this, the safe evacuation start time can be easily calculated regardless of the layout plan in the room of the building.

  The coefficient φ is preferably 0.90 or less. According to this, in addition to calculating a safer evacuation start time, it is possible to cover a generally safe evacuation start time in various rooms such as conference rooms, offices, and merchandise sales.

Further, the evacuation start time calculation system according to the present invention is a calculation system for an evacuation start time t _st until a occupant in the room starts evacuation when a fire occurs in the room of the building. , Smoke layer density ρ _s (kg / m ³ ), overall area A _R (m ² ), coefficient k related to the amount of fire plume, fire growth rate Q ₀ (kW / s ² ), ceiling height H _R ( m), an operation for calculating the evacuation start time based on the calculation method according to claim 1 or 2 by using an input means for inputting a coefficient φ of 0.95 or less and each numerical value input by the input means. And an output means for outputting the evacuation start time calculated by the calculating means.

  A computer-readable program according to the present invention causes a computer to function as the above-described evacuation start time calculation system.

  According to the present invention, a safe evacuation start time can be easily calculated regardless of a layout plan in a room of a building. For this reason, even when a design change of a living room occurs in a building that has been certified for evacuation safety by the Minister's certification, there is no need to repeat the performance evaluation and the Minister's certification for each change. Therefore, the degree of freedom to change the layout according to the customer's request is increased, and the design work efficiency can be improved.

It is the (a) top view and (b) sectional view of the living room used as the tenant concerning this embodiment. It is a figure which shows the idea of the transmission walk time to the child room which became deep. Is a graph showing the relationship between the time difference t _n and the transfer walking time t _{beta '.} It is the figure which showed the relationship between the floor area according to coefficient (phi), and time. It is the figure which showed the relationship between the floor area according to a use, and coefficient (phi). It is a block schematic diagram of an evacuation start time calculation system.

  Next, an embodiment of the present invention will be described.

  FIG. 1A is a plan view and FIG. 1B is a cross-sectional view of a living room serving as a tenant according to the present embodiment.

As shown in FIG. 1, this room has two doors on the hallway side, a parent room in the center, four child rooms on the back side, and each child room in the corner on the hallway side, The parent room and the child room are partitioned by a partition wall or the like up to the ceiling. In the following description, it is assumed that a fire has occurred in the parent room.
<Concept of room evacuation when calculating evacuation start time>

The safety goal is to complete the evacuation before the smoke drop in the room falls to the limit smoke layer height. The factors behind the delay in starting evacuation are that the children in the child room cannot immediately grasp the smoke status in the parent room, the child room is obstructed and the prospects are worse, and the L-shaped or U-shaped in large tenants In the case of a plan that is bent like a mold, the prospect may be worse. Therefore, in this verification, the evacuation start time is calculated in consideration of the delay in fire alarm.
<Calculation of evacuation start time>

In the present embodiment, the evacuation start time t _st is the smoke layer descent time when it is considered that smoke from the parent room has virtually accumulated up to 10% below the ceiling in the entire room, regardless of the position and area occupied by the child room. Is used. In other words, smoke from the parent room fires originally falls only in the parent room, but the smoke fall time is calculated virtually using the floor area of the whole room in consideration of the evacuation delay of the child room. This is a safe setting.
(Formula 7)
ρ _s (kg / m ³ ): smoke layer density A _R (m ² ): floor area of the entire room k: coefficient related to the amount of fire plume Q ₀ (kW / s ² ): fire growth rate H _R (m): Ceiling height

  In this way, the evacuation start time is based on Tanaka's simple smoke drop-off formula (Yasuyoshi Tanaka, “Introduction to Revised Architectural Fire Safety Engineering” issued by Japan Architectural Center, 2002. 1), similar to Equation 6 above. ing.

  The present invention is characterized in that the calculation formula of Formula 7 is used instead of the calculation formula (for example, Formula 2) conventionally used as the evacuation start time. The greatest feature of the present invention is that, when adopting the simple smoke descent formula, the floor area of the room, which is one of the parameters of the calculation formula, is set not only to the parent room but also to the whole room, and the smoke layer height is set to the ceiling. The height is set to 5% drop (ceiling height × 0.95) or less, more preferably 10% drop (ceiling height × 0.90). The verification of the fact that the mathematical formula with these settings functions as a safe evacuation start time will be described later. Note that Equation 7 is set to a 10% drop in the ceiling height (ceiling height × 0.90), and can be changed to other numerical values by replacing this 0.90 with the coefficient φ.

On the other hand, limit smoke layer fall time t _s is the target floor area of the parent chamber, smoke limit smoke layer height (typically, FL + 1.8 m: from the floor height of 1.8 m) and the time to drop to .
(Formula 8)
ρ _s : smoke layer density (kg / m ³ )
β: Parent room rate (ratio of the floor area of the parent room to the entire living room)
A _R: the entire room floor area (m ²⁾
k: Coefficient related to the amount of fire plume Q ₀ : Fire growth rate (kW / s ² )
H _R : Ceiling height (m)

In this way, Tanaka's simple smoke drop equation is also used to calculate the critical smoke layer fall time (Tanayoshi Yoshinaka, “Introduction to Revised Architectural Fire Safety Engineering”, published by Japan Building Center, 2002.) Is used as a base.
<Confirmation of safety of evacuation start time>

  The method of virtually igniting the entire room while ignoring the child room and setting the evacuation start time as the evacuation start time can be considered to be a safe setting in practice as follows.

When the smoke in the parent room falls to 10% below the ceiling of the parent room part, the person in the parent room notices the fire and starts evacuation. At this time, the person closest to the child room in the parent room However, if you walk to the entrance of the child room at the back of that position and transmit the fire, the child room evacuation start time is
The evacuation start time of the child room = the evacuation start time by 10% below the ceiling for the parent room + the transmission walking time to the child room. At this time, if the floor area of the child room is large, the “evacuation start time due to 10% smoke drop under the ceiling for the parent room” will be shortened, but the number of child rooms will increase, so the “walking time to the child room” will be longer. Become. On the other hand, if the child room floor area is small, the “evacuation start time due to 10% smoke drop under the ceiling for the parent room” will be longer, but since there are fewer child rooms, the “communication walking time to the child room” may be shorter. .

If the evacuation start time of the child room set in this way is 10% below the ceiling for the floor area of the entire room set earlier, that is, if the evacuation start time of Equation 7 is longer, The evacuation start time can be considered as a safe setting.
a) About walking distance

  Here, the transmission walking distance will be described. The walking time from the parent room to the child room varies depending on the child room plan, but from the child room arrangement pattern, the child room group is located in the back corridor than the plan where the child room is placed around the parent room. It is considered to be the longest in the plan to be deployed. Therefore, the transmission walking time that imagines the situation in which the child room is placed in the deep corridor will be considered next.

When a child room with a child room rate β ′ is arranged in the floor area Am ² (width Wm × depth Dm) as shown in FIG. 2, the transmission walking distance L _β (m) to the child room at the back is The following method can be considered as a simple method. However, the child room rate β ′ here refers to the ratio of all the non-parent rooms, and is expressed as β ′ = 1−β when the parent room rate is β.

  Method 1: As shown in FIG. 2A, the width of the child chamber portion is W, and the depth changes according to the child chamber ratio β ′. The walking distance of the passage from the parent room to the back child room door is β′D.

  Method 2: As shown in FIG. 2 (b), the depth of the child room portion is D, and the width changes according to the child room rate β ′. The walking distance of the passage from the parent room to the back child room door is β′W.

Based on the depth dimensions of the room, it was considered that Method 1 if the room shape was a rectangle with a long depth, and Method 2 if the shape of the room was a long rectangle, and the study was conducted for each parent room rate β. In this embodiment, the depth of the living room is 20 m, and the living room of 400 m ² or less is set as Method 1, and when it exceeds, the method 2 is set.
b) About the relationship between the time difference of smoke fall time and the transmission walking time

The formula for calculating the 10% smoke drop virtually covering the floor area of the entire room, that is, the formula for calculating the evacuation start time according to the present invention is the following formula 9.
(Formula 9)

On the other hand, the calculation formula of the 10% smoke drop targeting the floor area of the parent room when the parent room ratio β (child room ratio β ′ = 1−β) is Expression 10 below.
(Formula 10)

The time difference t _n between these two times is given by Equation 11.
(Formula 11)

here,
(Formula 12)
After all,
(Formula 13)
Thus, it can be seen that the time difference t _n is expressed by the floor area _AR and the parent room rate β. The transmission walking time t _{β ′} to the child room is t _{β ′} = L _β / v, where v (m / s) is the walking time.
In Method 1,
(Formula 14)
In Method 2, (Equation 15)
It becomes.

For example, ceiling height H _R = 2.8 (m), smoke layer density ρ _S = 1.0 (kg / m ³ ), v = 1.3 (m / s) [= 78 (m / min)], fire growth rate Q ₀ Substituting = 0.1129 (kW / s ² ) and studying Equations 13 to 15 results in the graph shown in FIG.

This graph shows the time difference t _n and the transmission walking time t _{β ′} between the smoke fall time when the entire living room is virtually targeted and the smoke fall time when only the parent room is targeted, for each parent room rate β. It is a representation.

As can be seen from this graph, when the parent room rate β is small, that is, when the child room floor area is large, the time difference t _n becomes long, and there is a sufficient margin if it is considered to walk and transmit to the end of the child room group. When the parent room ratio β is large, that is, when the child room floor area is small, the time difference t _n is shortened. However, since the child room floor area is small in the first place, it does not become a plan like a group of child rooms deep inside. It is considered that transmission walk from the parent room that I knew is unnecessary.

  Therefore, if the evacuation start time is the 10% smoke drop time for the floor area of the entire living room, the evacuation delay of the child room can be calculated safely regardless of the size of the child room floor area. I understand.

  In addition, depending on the planning of the child room, there is a possibility that a child room will be further deepened. However, it is assumed that the planning is performed so that the transmission walking time does not become longer than the transmission allowance time.

<Verification of coefficient φ at evacuation start time>

  As described above, the most important feature of the present invention is that, when adopting the simple smoke descending formula, the floor area of the living room, which is one of the parameters of the calculation formula, is set not only to the parent room but also to the entire living room. The height is set to be 5% lower than the ceiling height (ceiling height × 0.95) or less, more preferably 10% lowering (ceiling height × 0.90). In particular, the critical significance of 5% or 10% drop in smoke layer height as a parameter of the calculation formula will be verified.

When the smoke layer height from the floor is φH _R (0 <φ <1), when smoke starts to accumulate on the ceiling and falls to some extent, the fire is detected and evacuation starts. Φ for calculating the evacuation start time to be safer than the evacuation start time according to Formula 2 used in the notification or the like is as follows.
(Formula 16)

  In Expression 16, when φ is set to 0.95 (5% drop), 0.90 (10% drop), 0.85 (15% drop), and 0.80 (20% drop), the graph shown in FIG. 4 is obtained. From this graph, it can be seen that φ is 0.95 (5% drop), which is almost the same as the conventional method of notification, so φ is 0.95 or less, that is, 5% drop in ceiling height is the limit. As can be seen from this graph, when φ is a numerical value of 0.80 or more, it is generally below the limit smoke layer fall time.

In addition, when Expression 16 is developed around φ,
(Formula 17)
It becomes.

When the meeting room (Q ₀ = 0.016), light goods sales (Q ₀ = 0.08), office (Q ₀ = 0.1), and heavy goods sales (Q ₀ = 0.24) are set in Equation 17, the graph shown in FIG. become that way. From this graph, it can be seen that φ is 0.9 (10% drop) is a safe value for each type of room. If the floor area of the room is approximately 30 m ² or less, the safe φ may be less than 0.9. However, in a room with such a small floor area, there is almost no child room, and the delay in starting evacuation is a problem. Can be ignored.
<Configuration and flow of evacuation start time calculation system>

  Next, a system (hereinafter referred to as the present system) in which the above evacuation start time calculation method is applied to a computer will be described.

  As shown in FIG. 6, the system includes a control unit 100 that controls each unit centrally, an input unit 110 that inputs various data, a calculation unit 120 that calculates an evacuation start time, and various data and calculation results. A storage unit 130 for storing and an output unit 140 for outputting various data and calculation results are provided.

The input unit 110 includes: smoke layer density ρ _s (kg / m ³ ), floor area A _R (m ² ) of the entire room, coefficient k related to the amount of fire plume, and fire growth rate Q ₀ (kW / s ² ) Various data such as the ceiling height H _R (m) are input. For example, in the case of a PC, a keyboard and a mouse are used.

  The calculation unit 120 is configured mainly by a CPU (Central Processing Unit) together with the control unit 100, and calculates an evacuation start time or the like according to Equation 7. The program for calculating the evacuation start time may be downloaded from a recording medium, or may be downloaded from a network such as the Internet.

  The storage unit 130 is configured by a cache memory, a hard disk, or the like, and stores various data input by the input unit 110 and the evacuation start time calculated by the calculation unit 120.

  For example, in the case of a PC, the output unit 140 includes a monitor, and outputs an evacuation start time that is a calculation result stored in the storage unit 130.

Thus, when various types of data are input to the input unit 110, the calculation unit 120 calculates the evacuation start time according to Equation 7 and outputs it to the output unit 140. At this time, various data and the evacuation start time as the calculation result are stored in the storage unit 130 as needed.
In the present embodiment, the case where the coefficient φ is 0.90 has been described as an example, but other numerical values may be used as long as the numerical value is 0.95 or less.

DESCRIPTION OF SYMBOLS 100 ... Control part 110 ... Input part 120 ... Calculation part 130 ... Memory | storage part 140 ... Output part

Claims (4)

A method for calculating an evacuation start time t _st until a occupant in the room starts evacuation when a fire occurs in the room in the building,
The evacuation start time t _st (s) is the smoke layer density ρ _s (kg / m ³ ), the floor area A _R (m ² ) of the entire room, the coefficient k related to the amount of fire plume, and the fire growth rate Q ₀ (kW / s ² ), a ceiling height H _R (m), and a coefficient φ of 0.95 or less, and a calculation method of an evacuation start time, which is calculated by the following formula 1.
(Formula 1)
  The evacuation start time calculation method according to claim 1, wherein the coefficient φ is 0.90 or less. A system for calculating an evacuation start time t _st until a occupant in the room starts evacuation when a fire occurs in the room in the building,
Smoke density ρ _s (kg / m ³ ), floor area A _R (m ² ) of the entire room, coefficient k related to the amount of fire plume, fire growth rate Q ₀ (kW / s ² ), ceiling height H _R ( m), an input means for inputting a coefficient φ of 0.95 or less,
Calculation means for calculating the evacuation start time based on the calculation method according to claim 1 or 2, using each numerical value input by the input means;
An evacuation start time calculation system comprising: output means for outputting the evacuation start time calculated by the calculation means.   A computer-readable computer program for causing a computer to function as the evacuation start time calculation system according to claim 3.