Deep underground building and up-and-down combined personnel safety evacuation method for building clusters of deep underground building

Abstract

The invention belongs to the technical field of building emergency evacuation, and particularly discloses a safe personnel evacuation method for up-down combination of a deep underground building and a building cluster of the deep underground building. In combination with the concept of sharing a safe area in a deep underground building, a method of'upward-downward-upward 'simultaneous evacuation of three streams of people in a staircase in the vertical direction is provided. A single building is divided into upper, middle and lower evacuation spaces of the same level, and two evacuation direction conversion points and a shared safety area are arranged; and people in the upper evacuation space are evacuated to the ground through the first evacuation direction conversion point nearby. The personnel in the middle and lower evacuation spaces choose a second evacuation direction conversion point to evacuate and lead to a shared safety area; a deep underground building cluster technology with an infinite expansibility and toughness evacuation network is provided, and a new design and planning method is formed. The method has the advantages that the total evacuation time is limited, the reliability of the underground space under extreme disasters is greatly improved, and intensive and sustainable development is achieved.

Description

Technical Field

[0001] This invention belongs to the field of building emergency evacuation technology, specifically relating to a method for safe evacuation of personnel in deep underground buildings and their building clusters that combine vertical and horizontal structures. Background Technology

[0002] Currently, there is no clear concept for deep underground structures. Establishing a concept for deep underground structures, clarifying their types and characteristics, and conducting targeted research will help refine and develop related design methods, improve the efficiency of underground space resource development and utilization, and achieve intensive and sustainable development.

[0003] Therefore, combining existing concepts of underground architecture and underground space, the concept of deep underground architecture is proposed. This concept defines a building whose core structure is located within rock or soil layers at a depth of -50 to -100 meters as a "deep underground building." Deep underground buildings are diverse, including independent building units and usable sections extending downwards from surface buildings into this depth range. Their functions encompass underground parking garages, shopping malls, railway stations, tunnels, subways, storage facilities, laboratories, and living facilities, among others.

[0004] Currently, underground structures primarily employ upward evacuation methods, using the ground level as the sole evacuation endpoint. However, as the depth of underground structures increases, if all upward evacuation methods are used in deep underground buildings, the long upward evacuation distance significantly depletes the physical strength of evacuees, leading to a decrease in evacuation speed and an increase in overall evacuation time. Furthermore, during a fire, smoke spreads horizontally at a speed of 0.5-1 m / s and vertically at a speed of 3-5 m / s. The speed of smoke spread is faster than the upward speed of people, so evacuation routes quickly become filled with smoke. Since the upward evacuation direction of people is the same as the direction of smoke movement, failure to evacuate quickly can lead to suffocation and burns, resulting in serious injuries and deaths. Although existing designs use conventional refuge floors or refuge spaces to provide temporary shelter for evacuees, these are not absolutely safe areas; they serve only as buffer zones, not reliable evacuation endpoints. This fails to address the problems of limited evacuation routes, a fragile evacuation system, and low fault tolerance. Based on the above analysis, those skilled in the art urgently need a new method for the safe evacuation of people in deep underground buildings and their clusters, in order to improve evacuation efficiency and shorten the safe evacuation time of deep underground buildings. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of the prior art by providing a method for the safe evacuation of personnel in deep underground buildings and their clusters that combines vertical and horizontal evacuation. This method is based on the principle that personnel from different floors can evacuate to the nearest location. It also incorporates the concept of a shared safety zone in deep underground buildings and proposes a combined vertical and horizontal evacuation method, aiming to improve the evacuation efficiency and shorten the safe evacuation time of deep underground buildings.

[0006] The objective of this invention is achieved through the following technical solutions: A method for safe evacuation of personnel from deep underground structures and their clusters, comprising the following steps: S1: A basic unit consisting of a shared security zone and six deep underground buildings located on the outer ring of the shared security zone is a regular hexagonal layout. An underground building cluster is formed by combining several of the basic units. A connecting passage is provided between the shared security zone and each of the deep underground buildings on its outer ring. Each deep underground structure is vertically divided into three evacuation spaces: upper, middle, and lower, designated as evacuation space 1, evacuation space 2, and evacuation space 3 from top to bottom. A first evacuation direction switching point is located between the upper evacuation space 1 and the middle evacuation space 2, and a second evacuation direction switching point is located between the middle evacuation space 2 and the lower evacuation space 3. The floor where the second evacuation direction switching point is located has a connecting passage leading to the shared safe area. The evacuation direction of personnel in the first evacuation space is towards the surface above; the evacuation direction of personnel in the second and third evacuation spaces is towards the second evacuation direction switching point. S2: Determine the height division and evacuation time of the three evacuation spaces to minimize the total evacuation time; S2.1: Initially divide the heights of the three evacuation spaces, assuming the height of the first evacuation space is... h 1 The height of the second evacuation space is h 2 The height of the third evacuation space is h 3 The unit is m ; S2.2: Calculate the personnel density on the stairs in each evacuation space as a function of time t. βᵢ(t) The unit is person / m², and the calculation formula is: ; In the formula: i=1,2,3 Dimensionless; hi For the first i The height of the evacuation space is given in units of... m ; h f The height of the deep underground structure is given in units of 1. m ; S The number of staircases provided within a single evacuation space, in units of; m The rate at which people pass through a single stairwell safety exit. μ=(W) M / W P )*φ The unit is people per second; W P A person's shoulder width, in units of m ; W M Width of the stairwell safety exit, in units of m ; f The ideal rate of passage for a single person at a stairwell safety exit is expressed in person / second. h s The riser height of each staircase step, in units of m ; b Width of stairwell, unit: m ; c The length of each stair tread, in units of 1. m ; d The width of each stair tread, in units of m ; t Time, in seconds; p The number of people on each floor, in person; S2.3: Calculate the time-varying time within each of the aforementioned evacuation spaces. t Changing evacuation speed Vᵢ'(t) The unit is m / s The calculation formula is: ; In the formula: i=1,2,3 Dimensionless; t Time, in seconds. 0<t≤T si ; T si The time taken for a person in the i-th evacuation space to move unimpeded from the staircase on this floor to the staircase where the safety exit is located, in seconds; a For adjusting fatigue levels, a >0, dimensionless; βᵢ(t) If it is less than 1, then take 1; i The slope of the staircase is expressed in degrees (°). V i Let be the initial velocity of the evacuees within the i-th evacuation space, in units of . m / s ; S2.4: Calculate the evacuation time for each of the evacuation spaces. T i The calculation formula is: T i = T h + T si + T di ; In the formula: T h The horizontal movement time of people on each floor from the start of evacuation to the stairwell entrance on that floor, in seconds; T di The time, in seconds, is the time taken for personnel in the i-th evacuation space to queue at the stairwell exit after passing through the stairwell. T si The calculation formula is obtained by integrating the velocity-distance equation: ; S2.5: Based on step S2.4 T i Calculate the results and determine whether they meet the requirements. T 1 = T 2 = T 3 ; If satisfied T 1 = T 2 = T 3 Then output the height division of each evacuation space mentioned in step S3.1. h1 , h 2 , h 3 and evacuation time T 1 , T 2 , T 3 ; If not satisfied T 1 = T 2 = T 3 Then return to step S2.1 for further adjustments. h 1 , h 2 , h 3 .

[0007] People inside the first evacuation space evacuate upwards to the ground, people inside the second evacuation space in the middle evacuation space evacuate downwards, and people inside the third evacuation space at the bottom evacuate upwards to the shared safe zone. The vertical evacuation directions are opposite at the second evacuation direction conversion point. By determining the location of the second evacuation direction conversion point and using a staggered vertical staircase arrangement at the location of the second evacuation direction conversion point, it is ensured that the two streams of people located in the middle and the bottom evacuate simultaneously in the second evacuation space and the third evacuation space.

[0008] In step S1, the radius r of the shared safety zone and the hexagonal side length e of the basic unit and their positional relationship are determined. The calculation method for the spacing between the deep underground buildings in the basic unit is determined to ensure that the capacity of the shared safety zone meets the evacuation requirements and that the spacing between the deep underground buildings in the underground building cluster is reasonable, thus ensuring that the planning of the underground building cluster is reasonable.

[0009] Step S1 includes the following steps: S1.1: Calculate the number of people who need to be evacuated to the shared safe zone in each of the deep underground buildings, that is, the sum of the number of people in the second evacuation space and the third evacuation space in each of the deep underground buildings; S1.2: Based on the principle that the average net area per person in the shared safe zone is not less than 5m², calculate the minimum effective area Q of the shared safe zone. The calculation formula is as follows: ; In the formula: j=1，2，3，4，5，6 Dimensionless; HThe total building height of the deep underground structure is given in units of 1. m ; h 1j For the first j The height of the first evacuation space in the deep underground building is given in units of m ; h fj For the first j The floor height of the deep underground building described above, in units of m ; z j For the first j The number of shared security zones connected to the deep underground building, in units of [number]. p j For the first j The number of people on each floor of the deep underground building described above, in persons; S1.3: Calculate the radius r of the shared security zone using the following formula: ; Verify whether the radius r of the shared safety zone satisfies the radius constraint, which is as follows: ; In the formula: m The number of layers in the shared security zone is dimensionless. e The hexagonal side length of the basic unit is given in units of 1. m ; S1.4: Verify the spacing constraints between the deep underground structures, as follows: X=max{r+R j }，j=1,2,3,4,5,6 ; Y=max{R j+1 +R j }，j=1,2,3,4,5 ; e>max{X,Y,R 1 +R 6 } ; In the formula: X The minimum distance between the shared security zone and the deep underground structure, in units of m ; YThe minimum distance between adjacent deep underground structures, in units of m ; R j For the first j The radius of the deep underground structure described above, in units of m ; S1.5: Determine whether the radius constraint and spacing constraint are satisfied; If satisfied, output r, e, and Q; If the condition is not met, return to step S1.2.

[0010] The advantages of this invention are: The "top-down" strategy divides people into three groups using an algorithm, providing multi-directional and parallel paths to eliminate the bottleneck effect of the traditional all-upward method. By combining building safety-related parameters, the algorithm precisely optimizes the evacuation direction and transition point location, enabling the three groups of people to arrive at the destination simultaneously. This minimizes the safe evacuation time for large-scale crowd evacuation, completely solving the problems of long evacuation distances, long evacuation times, and excessive fatigue of evacuees in deep underground buildings, and achieving a theoretical limit compression of the total evacuation time.

[0011] The shared safety zone defined in this invention, compared to the traditional concept of refuge floors, is a "permanent shared safety zone" that is completely decoupled from the main structure, providing a theoretical basis for solving the problem of a single vertical evacuation path in deep underground buildings.

[0012] A design method for underground building clusters is proposed. Based on a resilient network with topological redundancy, the cluster configuration of shared safety zones provides at least two paths connecting different shared safety zones for each deep underground building unit, forming a resilient evacuation network with multi-point access, ring network mutual backup, and unlimited scalability, so as to save underground space resources and improve the utilization rate of underground space.

[0013] The method of safe evacuation of personnel in deep underground buildings and their clusters, which combines vertical and horizontal structures, greatly enhances the system's survivability and functional reliability under extreme disasters, achieving intensive and sustainable development. Attached Figure Description

[0014] Figure 1 This is a cross-sectional schematic diagram of the combined vertical and horizontal evacuation method for deep underground structures in this invention; Figure 2 This is a schematic diagram of the composition of the basic unit in this invention; Figure 3 This is a schematic diagram of an underground building cluster with a regular hexagonal layout composed of several basic units, as described in this invention. Figure 4This is a schematic diagram of the staircase misalignment design within the same staircase as the location of the second evacuation conversion point in this invention. Detailed Implementation

[0015] The features and other related features of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments, so as to facilitate understanding by those skilled in the art: Example: Figure 1 , 2 As shown in Figures 3 and 4, this embodiment specifically relates to a method for safe evacuation of personnel from deep underground buildings and their clusters, including the following steps: (S1) A shared safety zone is an underground space completely decoupled from the main structure, independent of but connected to the main underground building. It has independent evacuation routes leading to the surface. One shared safety zone can serve multiple deep underground buildings, and a deep underground building can be served by two or more shared safety zones. A shared safety zone is a "permanent safety zone," ensuring a safe evacuation endpoint. Located outside the main building, it is relatively isolated from the fire scene, thus avoiding direct impact from fire smoke. Simultaneously, fire-resistant materials and specialized construction measures enhance fire-resistant separation performance, preventing the spread of fire and smoke. Once evacuees enter this area, their evacuation is considered complete and they are in a safe state. A shared safety zone is theoretically an absolutely safe area, and its establishment helps provide more flexible and diverse escape options for deep underground buildings.

[0016] A basic hexagonal unit is formed by combining one shared security zone and six deep underground buildings located on the outer ring of the shared security zone. Several basic units are combined to form an underground building cluster. Connecting passages are provided between the shared security zone and each deep underground building on its outer ring.

[0017] The hexagonal structure is stable and highly expandable. By continuously connecting it in six directions, it can be infinitely expanded to eventually form a network of deep underground building clusters. Based on this layout, in the event of a fire in any deep underground building, people can evacuate to the nearest 2-3 connected shared safety zones. If one shared safety zone is temporarily unavailable, people can still move to other shared safety zones, achieving both pre-rescue evacuation and multi-point parallel evacuation. This disperses people, reduces bottlenecks, shortens evacuation time, and reduces the peak number of people in a single shared safety zone and the required underground space size. The networked nature of deep underground building clusters enables the sharing of shared safety zones, improving the safety, evacuation efficiency, and construction economy of deep underground buildings, while also providing a foundation for phased implementation and flexible expansion.

[0018] The deep underground structure is divided into three evacuation spaces along its depth: upper, middle, and lower, designated as Evacuation Space 1, Evacuation Space 2, and Evacuation Space 3 from top to bottom. A first evacuation direction switching point is located between Evacuation Space 1 (upper) and Evacuation Space 2 (middle), and a second evacuation direction switching point is located between Evacuation Space 2 (middle) and Evacuation Space 3 (lower). The floors containing the second evacuation direction switching points have connecting passageways leading to a shared safe zone. Personnel in Evacuation Space 1 are close to the ground and evacuate upwards to the surface. Personnel in Evacuation Space 2 are further from the ground and choose a safer, faster, and less physically demanding evacuation direction: downwards, pointing towards the second evacuation direction switching point for easy access to the shared safe zone. Personnel in Evacuation Space 3 are located at the deepest part of the underground structure and evacuate upwards, pointing towards the second evacuation direction switching point for easy access to the shared safe zone.

[0019] By setting two evacuation direction conversion points, the evacuation directions of personnel are rationally and orderly divided. Furthermore, by determining these conversion points, the optimal grouping of evacuees and the most reasonable location of the shared safe zone are identified, minimizing the total evacuation time and maximizing evacuation efficiency. Since personnel from both the second and third evacuation spaces are evacuated to the shared safe zone, the second evacuation direction conversion point serves not only as the evacuation direction but also as the floor where the shared safe zone is located. Considering that the upward and downward flow of people in the second and third evacuation spaces may create a bottleneck, a staggered staircase design is implemented within the same staircase at the second evacuation conversion point. Figure 4 As shown, the staircase is actually a staggered location. This staggering is to create separate evacuation paths, separating the flow of people in two directions to reduce interference and congestion, and to ensure the smooth evacuation of people in each direction.

[0020] In step S1, the radius r and the side length e of the hexagon of the shared safety zone are determined to ensure that the capacity of the shared safety zone meets evacuation requirements and that the building spacing is reasonable. The underground building cluster shares the shared safety zone.

[0021] It should be noted that a circle possesses excellent mechanical properties, better adapting to underground stress conditions and maintaining the stability of the building structure. Compared to a square or rectangle of the same area, a circle has the smallest outer surface area, reducing the contact area with the surrounding environment and better maintaining the stability of the building's internal environment. Therefore, a circle was chosen as the shape for deep underground buildings.

[0022] S1.1: Calculate the number of people who need to be evacuated to the shared safe zone in each deep underground building, which is the sum of the number of people in the second evacuation space and the third evacuation space in each deep underground building.

[0023] S1.2: Based on the principle that the average net area per person in the shared safe zone is not less than 5m², calculate the minimum effective area Q of the shared safe zone. The calculation formula is as follows: ; In the formula: j=1，2，3，4，5，6 Dimensionless; H The total building height of the deep underground structure is given in units of 1. m ; h 1j For the first j The height of the first evacuation space in the deep underground building is given in units of m ; h fj For the first j The floor height of the deep underground building described above, in units of m ; z j For the first j The number of shared security zones connected to the deep underground building, in units of [number]. p j For the first j The number of people on each floor of the deep underground building described above, in persons; S1.3: Calculate the radius r of the shared security zone using the following formula: ; Verify whether the radius r of the shared safe area satisfies the radius constraint, which is as follows (the maximum radius of the shared safe area is the incircle of the hexagon, so the maximum radius of the shared safe area is as follows): ; In the formula: m The number of layers in the shared security zone, dimensionless; e The side length of the hexagon of the basic unit is given in units of 1. m .

[0024] S1.4: Verify the spacing constraints between deep underground structures, as follows: X=max{r+R j }，j=1,2,3,4,5,6 ; Y=max{R j+1 +R j }，j=1,2,3,4,5 ; e>max{X,Y,R 1 +R 6 } ; In the formula: X The minimum distance between shared safety zones and deep underground structures, in units of m ; Y The minimum distance between adjacent deep underground structures, in units of m ; R j For the first j The radius of a deep underground building, in units of m .

[0025] It should be noted that the distance between deep underground buildings, and between deep underground buildings and shared safety zones, cannot be greater than the side length e of the hexagon.

[0026] S1.5: Determine whether the radius constraint and spacing constraint are satisfied; If satisfied, output r, e, and Q; If the condition is not met, return to step S1.2.

[0027] S2: Determine the height division of the three evacuation spaces and the evacuation time to minimize the total evacuation time.

[0028] S2.1: Initially divide the heights of the three evacuation spaces, assuming the height of the first evacuation space is... h 1 The height of the second evacuation space is h 2 The height of the third evacuation space is h 3 The unit is m .

[0029] S2.2: Calculate the population density on the stairs in each evacuation space as a function of time t. βᵢ(t) The unit is person / m², and the calculation formula is: ; In the formula: i=1,2,3 Dimensionless; h i For the first i The height of an evacuation space, in units of m ; h f The height of a deep underground building is expressed in units of 1. m ; S The number of staircases provided within a single evacuation space, expressed in units. m The rate at which people pass through a single stairwell safety exit. μ=(W) M / W P )*φ The unit is people per second; W P A person's shoulder width, in units of m Typically, 0.5m is used; W M Width of the stairwell safety exit, in units of m Typically, the depth is 0.8-1.8m; f The ideal rate of passage for a single person at a stairwell safety exit is expressed in person / second. h s The riser height of each staircase step, in units of m ; b Width of stairwell, unit: m ; c The length of each stair tread, in units of 1. m ; d The width of each stair tread, in units of m ; t Time, in seconds; p The number of people on each floor, in person.

[0030] It should be noted that when people first enter the stairwell, the number of people inside initially increases over time. After everyone has entered the stairwell, as the number of people on the stairwell reaches its maximum, people continuously exit through the emergency exits, and the number of people inside the stairwell decreases over time.

[0031] (a) It takes p / ( ) for everyone on each floor to enter the staircase. Sμ) The duration. 0 < t ≤ p / ( Sμ) This indicates the number of people on the stairs, which increases over time, from the number inside the stairs to the number of people on the stairs at that point; p / ( Sμ)<t This represents a segment of the staircase where everyone enters, and the number of people decreases over time. The core idea is to divide the change in the number of people in each segment by the area of ​​that staircase segment to obtain the population density.

[0032] (b) The stair area is determined by the height of each area and the stair parameters. The stair area is the length multiplied by the width of the stairwell, and then multiplied by the number of floors contained in each section to obtain the stair area: .

[0033] (c) The population density over time is the number of people entering the staircase minus the number of people exiting the staircase, which is then divided by the area of ​​each section of the staircase.

[0034] S2.3: Calculate the time-varying time within each evacuation space. t Changing evacuation speed Vᵢ'(t) The unit is m / s The calculation formula is: ; In the formula: k is the speed attenuation coefficient for adjusting the speed of people going up or down stairs, which is dimensionless; t Time, in seconds. 0<t≤T si ; T si The time taken for a person in the i-th evacuation space to move unimpeded from the staircase on this floor to the staircase where the safety exit is located, in seconds; a For adjusting fatigue levels, a >0, dimensionless; βᵢ(t) If it is less than 1, then take 1; i The slope of the staircase is expressed in degrees (°). V i Let be the initial velocity of the evacuees within the i-th evacuation space, in units of . m / s .

[0035] The evacuation speed within the evacuation space varies with time t and is affected by individual fatigue level, stair slope and personnel density. (1) The greater the stair slope, the slower the evacuation speed; (2) The greater the personnel density, the more congestion occurs, and the slower the evacuation speed; (3) In the early stage of fatigue, fatigue has a relatively small impact on evacuation speed, but its impact on speed gradually increases as fatigue level increases.

[0036] S2.4: Calculate the evacuation time for each evacuation space. T i The calculation formula is: T i = T h + Tsi + T di ; In the formula: T h The horizontal movement time of people on each floor from the start of evacuation to the stairwell entrance on that floor, in seconds; T di The time, in seconds, is the time taken for the i-th person in the evacuation space to wait in line at the stairwell exit after passing through the stairwell. T si The calculation formula is obtained by integrating the velocity-distance equation: .

[0037] The length of the evacuation path for a person on each floor's internal staircase is the length of the ramp on the steps plus the arc length of the two platforms. The length of the evacuation path within each evacuation space is the number of floors included multiplied by the path length on each floor.

[0038] Movement path on each floor of the stairs L inclination Calculation method: ; The path on the platform is an arc, and two arcs together form the circumference of a circle. The diameter of the circle is the width of the stair platform. The calculation formula is: L turning =π(2c+b).

[0039] S2.5: Based on step S2.4 T i Calculate the results and determine whether they meet the requirements. T 1 = T 2 = T 3 ; If satisfied T 1 = T 2 = T 3 Then output the height division of each evacuation space in step S3.1. h 1 , h 2 , h 3 and evacuation time T 1 , T 2 ,T 3 ; If not satisfied T 1 = T 2 = T 3 Then return to step S2.1 for further adjustments. h 1 , h 2 , h 3 .

[0040] The beneficial effects of this embodiment are: (1) By using the "top-down combination" strategy, the personnel are divided into three groups for parallel evacuation to avoid long-distance evacuation of all personnel upwards. During the evacuation process, the physical exhaustion of personnel will lead to increased evacuation difficulty and evacuation time, resulting in severe overcrowding and increased safety risks. By calculating and optimizing the location of the transfer point, the three groups of personnel can arrive at the destination at the same time, thus minimizing the safe evacuation time.

[0041] (2) Introducing the concept of “shared safety zone”, the shared safety zone defined in this invention is independent of the main building and serves as the evacuation endpoint. It has an independent evacuation route and advanced fire separation, providing a theoretically absolute safety environment and completely solving the problem of a single evacuation endpoint in deep underground buildings. Traditional refuge floors cannot serve as evacuation endpoints.

[0042] (3) In the design of underground building clusters, each building is connected to at least two shared safety zones to form a redundant evacuation network. Even if one shared safety zone fails, people can still turn to other shared safety zones to form a resilient evacuation network with multi-point access, ring network mutual backup and unlimited scalability, so as to save underground space resources, improve the utilization rate of underground space, and significantly enhance the system's disaster resistance resilience under extreme disasters.

Claims

1. A method for safe evacuation of personnel from deep underground buildings and their clusters, characterized in that... The evacuation method includes the following steps: S1: A basic unit consisting of a shared security zone and six deep underground buildings located on the outer ring of the shared security zone is a regular hexagonal layout. An underground building cluster is formed by combining several of the basic units. A connecting passage is provided between the shared security zone and each of the deep underground buildings on its outer ring. Each deep underground structure is vertically divided into three evacuation spaces: upper, middle, and lower, designated as evacuation space 1, evacuation space 2, and evacuation space 3 from top to bottom. A first evacuation direction switching point is located between the upper evacuation space 1 and the middle evacuation space 2, and a second evacuation direction switching point is located between the middle evacuation space 2 and the lower evacuation space 3. The floor where the second evacuation direction switching point is located has a connecting passage leading to the shared safe area. The evacuation direction of personnel in the first evacuation space is towards the surface above; the evacuation direction of personnel in the second and third evacuation spaces is towards the second evacuation direction switching point. S2: Determine the height division and evacuation time of the three evacuation spaces to minimize the total evacuation time; S2.1: Initially divide the heights of the three evacuation spaces, assuming the height of the first evacuation space is... h 1 The height of the second evacuation space is h 2 The height of the third evacuation space is h 3 The unit is m ; S2.2: Calculate the personnel density on the stairs in each evacuation space as a function of time t. βᵢ(t) The unit is person / m², and the calculation formula is: ； In the formula: i=1,2,3 Dimensionless; h i For the first i The height of the evacuation space is given in units of... m ; h f The height of the deep underground structure is given in units of 1. m ; S The number of staircases provided within a single evacuation space, in units of; μ The rate at which people pass through a single stairwell safety exit. μ = (W) M / W P )*φ The unit is people per second; W P A person's shoulder width, in units of m ; W M Width of the stairwell safety exit, in units of m ; φ The ideal rate of passage for a single person at a stairwell safety exit is expressed in person / second. h s The riser height of each staircase step, in units of m ; b Width of stairwell, unit: m ; c The length of each stair tread, in units of 1. m ; d The width of each stair tread, in units of m ; t Time, in seconds; p The number of people on each floor, in person; S2.3: Calculate the time-varying time within each of the aforementioned evacuation spaces. t Changing evacuation speed Vᵢ'(t) The unit is m / s The calculation formula is: ； In the formula: i=1,2,3 Dimensionless; t Time, in seconds. 0<t≤T si ; T si The time taken for a person in the i-th evacuation space to move unimpeded from the staircase on this floor to the staircase where the safety exit is located, in seconds; a For adjusting fatigue levels, a >0, dimensionless; βᵢ(t) If it is less than 1, then take 1; θ The slope of the staircase is expressed in degrees (°). V i Let be the initial velocity of the evacuees within the i-th evacuation space, in units of . m / s ; S2.4: Calculate the evacuation time for each of the evacuation spaces. T i The calculation formula is: T i = T h + T si + T di ； In the formula: T h The horizontal movement time of people on each floor from the start of evacuation to the stairwell entrance on that floor, in seconds; T di The time, in seconds, is the time taken for personnel in the i-th evacuation space to queue at the stairwell exit after passing through the stairwell. T si The calculation formula is obtained by integrating the velocity-distance equation: ； S2.5: Based on step S2.4 T i Calculate the results and determine whether they meet the requirements. T 1 = T 2 = T 3 ; If satisfied T 1 = T 2 = T 3 Then output the height division of each evacuation space mentioned in step S3.

1. h 1 , h 2 , h 3 and evacuation time T 1 , T 2 , T 3 ; If not satisfied T 1 = T 2 = T 3 Then return to step S2.1 for further adjustments. h 1 , h 2 , h 3 .

2. The method for safe evacuation of personnel from deep underground buildings and their clusters, as described in claim 1, is characterized in that... People inside the first evacuation space evacuate upwards to the ground, people inside the second evacuation space in the middle evacuation space evacuate downwards, and people inside the third evacuation space at the bottom evacuate upwards to the shared safe zone. The vertical evacuation directions are opposite at the second evacuation direction conversion point. By determining the location of the second evacuation direction conversion point and using a staggered vertical staircase arrangement at the location of the second evacuation direction conversion point, it is ensured that the two streams of people located in the middle and the bottom evacuate simultaneously in the second evacuation space and the third evacuation space.

3. The method for safe evacuation of personnel from deep underground buildings and their clusters, as described in claim 1, is characterized in that... In step S1, the radius r of the shared safety zone and the hexagonal side length e of the basic unit and their positional relationship are determined. The calculation method for the spacing between the deep underground buildings in the basic unit is determined to ensure that the capacity of the shared safety zone meets the evacuation requirements and that the spacing between the deep underground buildings in the underground building cluster is reasonable, thus ensuring that the planning of the underground building cluster is reasonable.

4. The method for safe evacuation of personnel from deep underground buildings and their clusters, as described in claim 3, is characterized in that... Step S1 includes the following steps: S1.1: Calculate the number of people who need to be evacuated to the shared safe zone in each of the deep underground buildings, that is, the sum of the number of people in the second evacuation space and the third evacuation space in each of the deep underground buildings; S1.2: Based on the principle that the average net area per person in the shared safe zone is not less than 5m², calculate the minimum effective area Q of the shared safe zone. The calculation formula is as follows: ； In the formula: j=1，2，3，4，5，6 Dimensionless; H The total building height of the deep underground structure is given in units of 1. m ; h 1j For the first j The height of the first evacuation space in the deep underground building is given in units of m ; h fj For the first j The floor height of the deep underground building described above, in units of m ; z j For the first j The number of shared security zones connected to the deep underground building, in units of [number]. p j For the first j The number of people on each floor of the deep underground building described above, in persons; S1.3: Calculate the radius r of the shared security zone using the following formula: ； Verify whether the radius r of the shared safety zone satisfies the radius constraint, which is as follows: ； In the formula: m The number of layers in the shared security zone is dimensionless. e The hexagonal side length of the basic unit is given in units of 1. m ; S1.4: Verify the spacing constraints between the deep underground structures, as follows: X=max{r+R j }，j=1,2,3,4,5,6 ； Y=max{R j+1 +R j }，j=1,2,3,4,5 ； e > max{X, Y, R} 1 +R 6 } ； In the formula: X The minimum distance between the shared security zone and the deep underground structure, in units of m ; Y The minimum distance between adjacent deep underground structures, in units of m ; R j For the first j The radius of the deep underground structure described above, in units of m ; S1.5: Determine whether the radius constraint and spacing constraint are satisfied; If satisfied, output r, e, and Q; If the condition is not met, return to step S1.2.

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