JP5141547B2 - Fire awareness time calculation method, program and system - Google Patents

Description

  The present invention relates to a method, a program, and a system for obtaining a time required for a room occupant to notice a fire in an architectural space.

  In general, when designing a building, the designer examines the evacuation safety performance of the building, i.e., examines whether the occupants in the building can safely evacuate from the building. This examination is examined based on the evacuation completion time obtained from the sum of the evacuation start time, the walking time, and the door passage time. Here, the evacuation start time is, for example, the time from when the fire occurs until the occupant in the building space notices the fire by visually observing the smoke. It is an important factor in the examination.

In Patent Document 1 and Non-Patent Document 1, the evacuation start time t _start [s] of the occupant in the building space is calculated by Equation 1 using the floor area A _area [m ² ] of the building space in which the fire has occurred. To do.
JP 2007-334683 A 2000 Ministry of Construction Notification No. 1441 Tanaka Yasuyoshi, “Introduction to Architectural Fire Safety Engineering”, revised edition, Nippon Building Center, January 2002, p. 232-234 Society of Fire Protection Engineers (SFPE), “THE SFPE HANDBOOK of Fire Protection Engineering” 3rd edition, National Fire Protection Association, January 2002. 4-30

  By the way, if there is no partition in the architectural space and the layout is good, the occupants in the architectural space can easily recognize the fire. However, if the layout is limited by the partition or shape of the building space, the occupants in the building space need time to recognize the fire. That is, in the above formula 1, there is a problem that the evacuation start time is calculated based only on the floor area of the building space, and the influence of the layout such as the partition and shape of the building space is not taken into consideration.

  The present invention has been made in view of such conventional problems, and in consideration of the layout of the building space, the occupants can observe the smoke generated by the fire and staying in the vicinity of the ceiling from the time of the occurrence of the fire. The purpose is to find the time until the fire is noticed.

  In order to achieve this object, the invention according to claim 1 is directed to a fire notice time for obtaining a time required for a person in the building space to notice a fire that has occurred in the building space. It is a calculation method, Comprising: Based on the design drawing of the said architectural space, the minimum area among the visual ceiling areas which can be seen when the said occupant looks around 360 degree | times from the arbitrary points in the said architectural space is the said architectural space Obtaining a visual rate that is a value divided by the total ceiling area of the above, based on the obtained visual rate, the smoke that is generated by the fire and stays near the ceiling is necessary for the occupant to notice Obtaining the required smoke diffusivity indicating the smoke diffusion status, obtaining the smoke diffusion area, which is the area of the ceiling covered with the smoke, based on the obtained required smoke diffusivity, and based on the obtained smoke diffusion area The smoke diffusion surface from the fire occurrence A fire detection time required for the occupant to know the occurrence of a fire based on the obtained smoke diffusion time. This is a knowledge time calculation method.

  According to the first aspect of the present invention, when there is a partition or the like in the building space and the prospect is limited, the layout of the building space is taken into consideration, and the vicinity of the ceiling generated by the fire from the time of occurrence of the fire By observing the smoke accumulated in the room, it is possible to determine the time until the occupant notices the fire.

  Invention of Claim 2 is the fire awareness time calculation method of Claim 1, Comprising: The said required smoke diffusivity is a place where the said occupant cannot see based on the said visual recognition rate calculated | required. A fire notice time calculation method characterized by showing a smoke diffusion state necessary for the occupant to notice smoke generated by the fire generated in step 1 and staying near the ceiling.

  According to the second aspect of the present invention, the occupant is aware of the fire by observing the smoke generated by the fire and staying in the vicinity of the ceiling from the time of the occurrence of the fire at the place where the occupant cannot see. Time to know can be calculated.

  Invention of Claim 3 is the fire awareness time calculation method of Claim 1 or 2, Comprising: The said required smoke diffusivity is more than the numerical value calculated | required by subtracting the said visual rate from 1, and 1 or less This is a fire awareness time calculation method.

  According to the third aspect of the present invention, the required smoke diffusivity can be easily and accurately determined in consideration of the prospects associated with the layout of the partition of the building space.

  Invention of Claim 4 is the fire awareness time calculation method in any one of Claims 1-3, Comprising: The said visual ceiling area is less than predetermined limit distance from the arbitrary points in the said building space. The fire awareness time calculating method is characterized in that the area is visible when the occupant looks 360 degrees from the point.

  According to the fourth aspect of the present invention, it is possible to easily and accurately determine the fire awareness time even in an architectural space having a layout that can be seen far away by considering the distance at which smoke can be visually observed. In other words, although it depends on the sight of the occupants, generally the nearby smoke is well visible and the distant smoke is difficult to see, but according to the present invention, the distance between the smoke and the occupants and the visibility of the smoke The relationship can also be taken into account.

The invention according to claim 5 is the fire awareness time calculation method according to any one of claims 1 to 4, wherein the heat source heat generation rate Q _f [kW] is a fire growth rate Q ₀ [kW / s. ⁿ ], time t [s], and power n for time, and when given by Q _f = Q ₀ t ⁿ , the obtained smoke diffusion area A _s [m ² ] and the smoke generation coefficient β [ m ^4/3 / kJ ^1/3 s ^2/3 ], ceiling height H _f [m], fire growth rate Q ₀ [kW / s ⁿ ], and power n for time, The fire awareness time calculating method is characterized in that the smoke diffusion time t _s [s] is obtained by an equation.

According to the invention described in claim 5, it is only necessary to substitute appropriate specific numerical values for the input parameters of the smoke generation coefficient β, the ceiling height H _f , the fire growth rate Q _0, and the power _multiplier n for time. For example, the fire awareness time can be obtained immediately.

  The invention according to claim 6 is a fire awareness time calculation program for obtaining a time required for a resident in a building space to notice a fire that has occurred in the building space. Based on the design drawing of the architectural space, the minimum ceiling area of the visual ceiling area that can be seen when the occupant looks around 360 degrees from an arbitrary point in the architectural space is the total ceiling area of the architectural space. A step of obtaining a visual rate which is a value obtained by dividing, and based on the obtained visual rate, diffusion of the smoke necessary for the occupant to notice smoke generated by the fire and staying near the ceiling Obtaining a necessary smoke diffusivity indicating a situation, obtaining a smoke diffusion area which is an area of a ceiling covered with smoke based on the obtained required smoke diffusivity, and determining the obtained smoke diffusion area On the basis of A step of obtaining a smoke diffusion time required from the occurrence of the fire to the smoke diffusion area, and a fire notice required for the occupant to notice the occurrence of the fire based on the obtained smoke diffusion time A fire awareness time calculation program characterized in that a step for obtaining time is executed.

  According to the sixth aspect of the present invention, the fire awareness time can be determined easily and accurately by using the fire awareness time calculation method on a computer. In addition, the program can be distributed using an electric communication line such as the Internet, so that the applicant can easily use the fire awareness time calculation method.

  The invention according to claim 7 is a fire awareness time calculation system for obtaining a time required for an occupant in an architectural space to notice a fire that has occurred in the architectural space, wherein Based on a design drawing of the space, a visual rate that is a value obtained by dividing the visual ceiling area visible when the occupant looks around 360 degrees from an arbitrary point in the architectural space by the total ceiling area of the architectural space. Based on the obtained visual rate calculation unit and the obtained visual rate, the smoke necessary for the occupant to recognize the smoke generated by the fire and staying in the vicinity of the ceiling is indicated. A smoke diffusivity calculating part for obtaining a diffusivity, a smoke diffusing area calculating part for obtaining a smoke diffusing area that is an area of a ceiling covered with the smoke based on the obtained required smoke diffusivity, and the obtained smoke Based on the diffusion area, A smoke diffusion time calculation unit for obtaining a smoke diffusion time required to reach the smoke diffusion area, and a fire notification required for the occupant to recognize the occurrence of a fire based on the obtained smoke diffusion time A fire awareness time calculation system comprising: a fire awareness time calculation unit for obtaining time.

  According to the seventh aspect of the present invention, the fire awareness time can be easily and accurately obtained by using the data processing system.

  According to the present invention, in consideration of the layout of the building space, it is possible to obtain the time until the occupant notices the occurrence of the fire by visually observing the smoke.

=== First Embodiment ===
FIG. 1 is a plan view showing a partition of an architectural space 1 for obtaining a time required for a resident to notice a fire using the fire awareness time calculation method of the present invention. In the present embodiment, it is necessary for the occupant 2 in the building space 1 partitioned as shown in FIG. 1B and FIG. 1C to notice the fire that has occurred in the building space 1 where it cannot be seen. Ask for time.

  FIG. 2 is a flowchart showing the procedure of the fire awareness time calculation method in the present embodiment.

First, the visual rate C _v [%] is obtained based on the design drawing of the building space (S202). Here, the visual rate C _v [%] is the minimum area of the visual ceiling area A _v [m ² ] that can be seen when the occupant looks around 360 degrees from an arbitrary point in the architectural space. Of the total ceiling area A _c [m ² ].

In the example shown in FIG. 1, the partition extends from the right wall of the 400 m ² building space toward the center, but the entire building space can be seen from the position shown in FIG. 1A. That is, viewing the ceiling area _{A v} in this position is 400 meters ^2. On the other hand, from the position shown in FIG. 1B, a part of the ceiling of the building space cannot be seen by being blocked by the partition, and the visual ceiling area A _v [m ² ] is 300 m ² . In addition, from the position shown in FIG. 1C, half of the ceiling of the building space cannot be seen by being similarly blocked by the partition, and the visual ceiling area _Av is 200 m ² . Thus, the minimum value of the visual ceiling area _{A v} of the architectural space is 200 meters ^2, visually rate _C v = 50% is obtained when dividing it by the total ceiling area _A c = 400m ^2. Note that the total ceiling area A _c [m ² ] is obtained from a drawing or the like of the building space.

Next, the required smoke diffusion rate C _s [%] is calculated based on the visual rate C _v [%] obtained above (S204). Here, the required smoke diffusivity C _s [%] means that the occupant is aware of the fire by observing the smoke generated by the fire that occurred in a place where the occupant cannot see, and staying near the ceiling. This shows the minimum required smoke diffusion status. In addition, a place that cannot be seen is a place that cannot be directly seen from the position of the occupant by being blocked by a partition wall, or a place that is difficult to see even if it is not blocked by a partition in a large room.

FIG. 3 is a conceptual diagram showing the relationship between the diffusion rate of smoke generated by a fire and staying in the vicinity of the ceiling and the visual inspection rate. In the example shown in FIG. 3A, occupants who are located a visual index 75%, in order to SatoshiTomo fire occurring behind the partition is a need smoke spreading factor C _s is more than 25% there It is enough. That is, if necessary smoke spreading factor C _s is more than 25%, it means that leaks to the portion that can be further visible on the person in the room filled smoke a part that can not be visually person in the room smoke Satoru I can know. Thus, the fire awareness condition K [%] for the occupant to sense smoke needs to satisfy K ≦ C _s + C _v and 100% ≦ K ≦ 200%. In the following, K = 100%, but the value of the fire awareness condition K may be increased in order to set it to the safe side. As shown in FIG. 3B, the necessary smoke diffusivity C _s = 50% is obtained by subtracting the visual rate C _v = 50% calculated in S202 from the fire awareness condition K = 100%.

Then, the smoke diffusion area A _s [m ² ] is calculated based on the total ceiling area A _c [m ² ] and the required smoke diffusion rate C _s [%] obtained above (S206). Specifically, by multiplying the required smoke spreading factor C _s [%] to the total ceiling area A _c [m ^2], and calculates the smoke diffusion area A _s.

Furthermore, based on the smoke diffusion area _{A s} ^{[m 2],} obtaining the smoke diffusion area _{A s} ^{[m 2]} and required until smoke diffusion time _{t s} [s] from the fire (S208). Smoke diffusion time _{t s [s]}
Is specifically expressed as Equation 2.

Here, if the specific numerical values corresponding to these input parameters β, A _s , H _f , n and Q ₀ are substituted, the smoke diffusion time t _s [s] can be calculated. The ceiling height _Hf is acquired from a drawing or the like of the building space. n is a value indicating the nature of the heat generation rate of the fire source. In the partitioned building space targeted in this embodiment, it is common to use a fire source (n = 2) that increases with the square of time. is there. Fire growth rate Q ₀ is, evacuation safety fire growth rate due to the combustion of the verification method storing combustible materials of fire space using [kW / s ^2] and the fire growth rate due to the combustion of the interior material of the fire space [kW / s ^2] Or calculated from the result of a combustion test of combustible material assumed in the building space.

  Note that the derivation method of Expression 2 will be described later.

Based on the smoke diffusion time t _s [s], a fire _notice time t _notice [s] required for the occupant to _{notice the} fire from the time of the fire occurrence is obtained (S210). Here, since the smoke after the smoke diffusion time t _s [s] has spread to a visible area, the occupant can immediately recognize a fire. Therefore, the fire awareness time t _notice [s] is basically equal to the smoke diffusion time t _s [s].

  As described above, according to the present embodiment, in consideration of the layout of the building space such as partitions and shapes, smoke generated by the fire and staying in the vicinity of the ceiling from the point of time when the fire occurred in a place where the occupants cannot see it. The time until the occupant notices the fire can be obtained by visual inspection.

  In addition, according to the present embodiment, by calculating based on the visual ceiling area at the position with the worst line of sight in the building space, it is possible to easily and accurately obtain the fire awareness time standing on the safe side. .

By the way, the calculation method of fire _notice time _tnotice [s] of this embodiment can be easily performed using a general data processor represented by a personal computer. For example, the data processing device includes a central processing unit (CPU), a data recording device such as a hard disk device, an output device such as a monitor, an input device such as a keyboard, and a data reading device such as a CD-ROM drive device. A personal computer with a normal configuration can be used.

The data recording apparatus stores in advance a calculation program for calculating the above-described equation 2, and the CPU reads and executes the calculation program. That is, substituting the specific numerical values input by the input device into the input parameters β, A _s , H _f , Q ₀ and n in Equation 2, to calculate the fire awareness time t _notice [s], Then, the fire awareness time _tnotice [s], which is the calculation result, is displayed on the monitor.

Here, general-purpose spreadsheet software such as “Microsoft Excel” (trademark) of US Microsoft Corporation can be used as the arithmetic program. For example, when the “Microsoft Excel” is started, a worksheet composed of a large number of cells arranged vertically and horizontally is displayed on the monitor, and the designer can change the formula 2 into a predetermined cell (reference source cell). input. At this time, the input parameters constituting the expression 2 are associated with a reference destination cell for inputting a specific numerical value of the input parameter so that the input parameter can be calculated in the predetermined cell (reference source cell). . Therefore, if a specific numerical value is input to the reference cell, the formula 2 is automatically calculated based on the specific numerical value, and the fire awareness time _tnotice [s] as the calculation result is calculated for each reference source cell. And is displayed on the monitor.

  Such a calculation program may be recorded in advance in a data recording device, or a calculation program recorded in a data recording medium such as a CD-ROM may be read by the data reading device. good. Furthermore, the personal computer may be connected to a telecommunication line such as the Internet and downloaded from a server computer connected to this line.

=== Derivation Method of Equation 2 ===
The derivation method of Equation 2 is as follows.

First, according to Non-Patent Document 2, the fire source heat generation rate of a fire generated in a building space is given by Equation 3.

The diffusion of the smoke layer formed near the ceiling due to the fire is considered to be constant because the temperature rise of the smoke layer is small at the initial stage after the fire occurs, and the smoke diffusion area A of the smoke layer is considered using the relationship of mass conservation. A prediction formula of _s [m ² ] is derived.

FIG. 4 is a conceptual diagram of derivation of the smoke diffusion area. The figure shows a state in which when a fire 12 occurs in a room 10, a smoke plume 14 is formed by a fire plume 16 generated by the fire 12 flowing near the ceiling of the room. In the state shown in the figure, since the gas flows into and out of the smoke layer 14 only by the inflow of the fire plume 16, according to Non-Patent Document 2, the mass conservation equation of the smoke layer 14 can be expressed by Equation 4.
Here, m _p is the flow rate of the fire plume 16 [kg / s], with the ceiling height H _{f [m]} and the thickness Z _s of Kemuriso 14 _[m], is calculated by Equation 5. In the non-patent document 2, _{k m} in Formula 5 is 0.08, _{Q f} is Q, _{H-Z s} is expressed as z.
However, k _m is the entrainment coefficient of a fire plume ^{16 [kg / kJ 1/3 m 5/3} s 2/3].

Here, since the thickness Z _s [m] of the smoke layer 14 is known to be substantially proportional to the ceiling height H _f [m] according to Non-Patent Document 3, the thickness Z _s of the smoke layer 14 is known. _The proportionality constant of _s [m] to the ceiling height H _f [m] is given as Equation 6 as k _s .
When the ceiling is horizontal, the volume V [m ³ ] of the smoke layer 14 is expressed by Equation 7.
Further, the left side of Expression 7 can be transformed as Expression 8.
Furthermore, Expression 9 is obtained by substituting Expression 5 into the left side of Expression 4 and using the relationship of Expression 8.
Then, substituting Equation 3 into Equation 9 and rearranging it,
It becomes.

By integrating the equation 10, equation 11 is obtained as a prediction formula smoke spread area A _s at time t.
Also, if Rearranging Equation 11 with respect to time t, the prediction equation of time t smoke spread area is A _s is obtained as Equation 12.
Here, when Expression 6 is substituted into Expression 12 and rearranged, Expression 13 is obtained.
However, (beta) is as Formula 14.
Here, according to Non-Patent Document 2, beta is _{k m = 0.08 [kg / kJ} 1/3 m 5/3 s 2/3], ρ = 1.0 [kg / m 3], a and According to Non-Patent Document 3, since k _s = 0.112, substituting these numerical values into Equation 14, β = 0.59 is obtained.

=== Other Embodiments ===
As mentioned above, although embodiment of this invention was described, this invention is not limited to this embodiment, The deformation | transformation as shown below is possible in the range which does not deviate from the summary.

FIG. 5 is a diagram showing another calculation concept of the visual ceiling area A _v [m ² ] that is the basis for calculating the visual rate C _v [%]. When a fire breaks out in a small building space, it is easy to recognize the fire because smoke can be confirmed at a relatively close position. On the other hand, when a fire breaks out in a large building space, even if the smoke diffusivity is the same, the distance from the occupant to the smoke layer becomes relatively large, making it difficult to recognize the fire. Here, assuming that the limit distance at which the occupant can sense smoke is R [m], the portion that can be seen within the radius R when looking around 360 degrees from a certain point is the visual ceiling area A _v [m ² ]. Asking. The visual rate C _v [%] is obtained by dividing the visual ceiling area A _v [m ² ] by the total ceiling area A _c [m ² ]. The limit distance R depends on the brightness of the building space, the ceiling height, and the like, but may be set with reference to the installation interval of guide lights and guide signs.

FIG. 6 is a diagram showing yet another concept of calculating the visual rate C _v [%]. For example, when calculating the visual rate C _v [%] of a U-shaped building space as shown in the figure, the building space is divided into five blocks A, B, C, D, and E for convenience. For each block, the minimum visual ceiling area A _v [m ² ] and the corresponding visual rate C _v [%] are obtained. For example, if each block is 20 m ² , as shown in the figure, the viewing rate of block A and block D is 80%, the viewing rate of block C is 60%, and the viewing rate of block B and block E is 40%. It becomes. In this case, the fire awareness time _tnotice [s] for each block can be obtained.

It is a top view which shows the partition of the building space which calculates | requires the time required for an occupant to notice a fire using the fire notice time calculation method of this invention. It is a flowchart which shows the procedure of the fire awareness time calculation method in this embodiment. It is a conceptual diagram which shows the relationship between the spreading | diffusion rate of the smoke which arises by fire, and stagnates near a ceiling, and a visual inspection rate. It is a conceptual diagram of derivation | leading-out of smoke diffusion area. It is a figure which shows another calculation concept of the visual ceiling area used as the calculation base of a visual rate. It is a figure which shows another calculation concept of a visual rate.

Explanation of symbols

1 Building Space 2 Residents 3 Fire 10 Room 12 Fire 14 Smoke Layer 16 Fire Plume

Claims (7)

A fire awareness time calculation method for obtaining a time required for a resident in an architectural space to notice a fire that has occurred in the architectural space,
Based on the design drawing of the architectural space, the smallest visible ceiling area that can be seen when the occupant looks around 360 degrees from an arbitrary point in the architectural space is divided by the total ceiling area of the architectural space. To obtain the visual rate,
Based on the obtained visual rate, obtain the smoke diffusion rate necessary to indicate the smoke diffusion status necessary for the occupant to notice the smoke generated by the fire and staying near the ceiling,
Based on the calculated required smoke diffusivity, obtain a smoke diffusion area that is the area of the ceiling covered by the smoke,
Based on the obtained smoke diffusion area, obtain the smoke diffusion time required from the occurrence of the fire to the smoke diffusion area,
A fire awareness time calculation method characterized in that, based on the obtained smoke diffusion time, a fire awareness time required for the occupant to notice the occurrence of a fire is obtained. The fire awareness time calculation method according to claim 1,
The required smoke diffusivity is based on the obtained visual rate so that the occupant can notice the smoke that is generated by the fire that has occurred in a place where the occupant cannot see and stays near the ceiling. A fire awareness time calculation method characterized by indicating a necessary diffusion state of the smoke. The fire awareness time calculation method according to claim 1 or 2,
The fire awareness time calculation method according to claim 1, wherein the required smoke diffusivity is greater than or equal to a value obtained by subtracting the visual rate from 1 and less than or equal to 1. A fire awareness time calculation method according to any one of claims 1 to 3,
The visual ceiling area is within a predetermined limit distance from an arbitrary point in the architectural space, and is an area that can be seen when the occupant looks around 360 degrees from the point. Knowledge calculation method. A fire awareness time calculation method according to any one of claims 1 to 4,
When the heat source heating rate Q _f [kW] is given by Q _f = Q ₀ t ⁿ from the fire growth rate Q ₀ [kW / s ⁿ ], the time t [s], and the power _multiplier n for time, The determined smoke diffusion area A _s [m ² ], the smoke generation coefficient β [m ^4/3 / kJ ^1/3 s ^2/3 ], the ceiling height H _f [m], and the fire growth rate Q _A method for calculating the fire awareness time, wherein the smoke diffusion time t _s [s] is obtained by the following equation using ₀ [kW / s ⁿ ] and a power multiplier n with respect to time.
A fire awareness time calculation program for obtaining a time required for a occupant in an architectural space to notice a fire that has occurred in the architectural space,
On the computer,
Based on the design drawing of the architectural space, the smallest visible ceiling area that can be seen when the occupant looks around 360 degrees from an arbitrary point in the architectural space is divided by the total ceiling area of the architectural space. A step of obtaining a visual rate that is a measured value;
Based on the obtained visual rate, obtaining a smoke diffusion rate necessary to indicate the smoke diffusion state necessary for the occupant to notice smoke generated by the fire and staying near the ceiling; and
Based on the determined required smoke diffusivity, obtaining a smoke diffusion area that is an area of a ceiling covered with the smoke;
Based on the determined smoke diffusion area, obtaining a smoke diffusion time required from the occurrence of the fire to the smoke diffusion area;
Obtaining a fire notice time required for the occupant to notice the occurrence of a fire based on the obtained smoke diffusion time; and
A fire awareness time calculation program characterized in that A fire awareness time calculation system for obtaining a time required for a resident in an architectural space to notice a fire that has occurred in the architectural space,
A blueprint acquisition unit for acquiring a blueprint of the architectural space;
Based on the design drawing of the building space acquired by the design drawing acquisition unit, the total ceiling area of the building space is the visual ceiling area that can be seen when the occupant looks around 360 degrees from an arbitrary point in the building space. A visual rate calculation unit for obtaining a visual rate, which is a value divided by
Based on the visual rate obtained by the visual rate calculation unit, a required smoke diffusion rate indicating the diffusion state of the smoke necessary for the occupant to notice smoke generated by the fire and staying near the ceiling. The required smoke diffusivity calculator,
Based on the required smoke diffusivity obtained by the smoke diffusivity calculation unit, a smoke diffusion area calculation unit for obtaining a smoke diffusion area that is an area of a ceiling covered with the smoke;
Based on the smoke diffusion area obtained by the smoke diffusion area calculation unit, a smoke diffusion time calculation unit for obtaining a smoke diffusion time required from the occurrence of the fire to the smoke diffusion area;
Based on the smoke diffusion time obtained by the smoke diffusion time calculation unit, a fire awareness time calculation unit for obtaining a fire awareness time required for the occupant to notice the occurrence of a fire;
A fire awareness time calculation system comprising: