CN111882834B

CN111882834B - Implementation method of collapse early warning system under large-space roof fire disaster

Info

Publication number: CN111882834B
Application number: CN202010718326.3A
Authority: CN
Inventors: 尹亮; 阚强; 李智鸿
Original assignee: Shanghai Xiaohong Information Technology Co ltd; Tianjin Fire Research Institute of MEM
Current assignee: Shanghai Xiaohong Information Technology Co ltd; Tianjin Fire Research Institute of MEM
Priority date: 2020-07-23
Filing date: 2020-07-23
Publication date: 2023-08-22
Anticipated expiration: 2040-07-23
Also published as: CN111882834A

Abstract

The invention relates to a realization method of a collapse early warning system under a large-space roof fire disaster, wherein a detection part is arranged on a roof corresponding to a roof structure grid to be detected, obtains the dynamic temperature and the dynamic space coordinates of a near-roof of a detected point position, transmits data to the outside in a wireless and acoustic emission mode, and immediately sends out visual early warning in an optical display mode; the disposal part is arranged in a ground safety area around the fire building, receives the dynamic temperature data and dynamic space coordinate data of the near-roof of the detection point positions sent by each detection part in a wireless and sound identification mode, combines the manually input building and roof structure information data to perform calculation, and sends sound early warning and wireless early warning to related personnel according to different early warning levels; compared with the prior art, the system predicts and early warns the whole collapse process of the area of the roof severely affected by the fire disaster and the whole roof from the two angles of the critical temperature and the bearing capacity, and has few instrument erection and huge public safety benefit.

Description

Implementation method of collapse early warning system under large-space roof fire disaster

Technical Field

The invention relates to the field of building fire accident emergency rescue, in particular to a method for realizing a collapse early warning system under a large-space roof fire, which is used for predicting and early warning the collapse process under the fire of a roof structure (a space grid structure, a bent frame and a rigid frame structure) containing a large-space place, and realizing the aim of guaranteeing the safety of users in a building, particularly fire-fighting rescue workers.

Background

In a fire accident, the building structure is at risk of collapsing, which threatens the safety of the user who is not evacuated in time and the fire-fighting rescue workers, and also increases property loss. Prediction of collapse in a building structure fire accident is a realistic requirement for emergency disposal of the current building fire accident, but is also a worldwide problem. In general engineering and disaster monitoring, various sensors can be arranged in contact with a monitored part of a building before a disaster occurs and are arranged at a predictable key position, such as application number: CN201811485370.3 uses an axial force sensor, a horizontal and relative displacement sensor; application number: cn201220315799.X uses a tilt sensor; application number: CN201911135600.8 uses a plurality of laser light sensitive elements to accurately calculate the beam offset distance; application number: CN201921586546.4 uses vibration sensors when monitoring dam collapse; application number: CN201910732356.7 uses pressure sensors in monitoring coal mine collapse; application number: CN201620344377.3 uses an infrared emitter, a transverse mirror, and an infrared receiver; application number: CN201320478138.3 uses strain gauges, etc. However, the instruments and equipment for monitoring collapse cannot be purposefully arranged in advance due to random occurrence of fire, the environmental conditions after the occurrence of the fire are different from normal temperature, the high temperature, dense smoke and spreading environment become the biggest difficulty of field operation, personnel cannot arrange related instruments and accessories close to a fire area, the conditions of reduced applicability and reliability of the existing equipment, disturbed information transmission and the like can also occur, and the difficulty of observation can also be increased due to weather factors.

Aiming at the requirements and challenges of the disposal of fire building collapse accidents, the current technology makes various attempts from different emphasis, and the brief overview is as follows:

(1) Measurement techniques for displacement (velocity, acceleration), including: deformation, tilting, deflection, etc.

A. A method for obtaining single-point three-dimensional coordinates by using a laser total station. The total station is widely applied to engineering quality control and maintenance in the fields of construction, highway bridges and the like, belongs to the visual measurement technology, and improves the identification degree of targets by the aid of the laser and automatic tracking technology. However, when one instrument is continuously observed, only one single-point target can be tracked, and the instrument is easily interfered by high-temperature smoke. Application number: CN201711067894.6 proposes an apparatus and method for monitoring building deformation by effectively using a total station, in order to solve the problems that the laser transmitter is expensive for building deformation measurement and the common total station is used for replacing the existing method which has advantages but consumes labor in monitoring and data conversion. Analysis finds that: the key problems related to the implementation of the technology, such as monitoring from the front, the back, the left, the right or more directions of a fire disaster building, monitoring three-dimensional coordinate data of monitoring points on the building, the fact that the monitoring points are standard points on the building or fixed points of the building, warning thresholds, dangerous thresholds and the like, are clear. The method is characterized in that the position of the building which cannot be judged to be a critical monitoring point in the fire disaster, the critical point cannot be continuously monitored, and the method is characterized in that if a fixed point of the building is unsuitable, a calibrator is temporarily installed for the monitoring point of the fire disaster building, so that the implementation of the technology is critical. Meanwhile, the total station is certainly required to be automatically tracked, has no price advantage compared with a laser transmitter, is used for a plurality of stations, and cannot continue to automatically track once an initial tracking target exceeds the field of view of the total station, so that the total process real-time performance may not be realized. The wireless transmission between the total station and the monitoring platform is a technology which is known in the fields of bridge monitoring, house measurement and the like. The goal of providing reliable assurance for firefighter life safety cannot be achieved in general;

B. A method for visually observing the position change of a building mark relative to a laser array. Application number: CN201720777637.0 provides a low-cost and high-precision non-contact monitoring means adopting a laser circular spot transverse approximately equidistant array for the purpose of detecting deformation of a building in advance in a fire disaster and guaranteeing life safety of fire fighters. Analysis finds that: the application of the device also depends on the existing fixed references (further application number: CN201710519707.7 indicates that the building characteristics used as references (lines) comprise window edges, door edges, building outer edges, beam columns or building outer surface edges), which brings difficulty to the application of the device, on the one hand, the references can be far away from the initial collapse position of the building and can not reflect easy deformation (further application number: CN201710519707.7 indicates that the deformation before collapse of the fire building is mainly whole or partial transverse inclination), and on the other hand, the selection of the references depends on fire scene information and personal experience obtained by operators, which brings difficulty to accurate monitoring; although the laser of the building can avoid obvious flame and smoke positions and reduce the influence of external environment on monitoring results, the local collapse of the building actually occurs from the positions, and dense smoke and high-temperature gas inevitably influence the path of the laser. In conclusion, the device has a large feasibility problem in predicting the collapse of the building in the fire scene;

C. The method utilizes multiple angles to measure the distance change of a single target point in the linear direction so as to analyze the relative change of three-dimensional space coordinates (three linear distance measuring instruments observe one point at the same time). Application number: CN201710378861.7 discloses a monitoring point micro displacement monitoring system with a long-distance measuring probe being a radar probe or a laser ranging probe. The distance detection component is used for detecting the distance from the measured point to the detection device, and the distance change condition of the measured point can be calculated through continuous recording; in order to improve the test precision of the system and reduce false alarm behaviors, (application number: CN 201710378847.7) also discloses an early warning system which is formed by a second detection unit (short-range detection assembly) and a third detection unit (medium-range detection assembly) which are matched together; application number: CN201710378847.7 discloses a method for using the displacement monitoring system, namely, firstly, taking the coordinates of the monitored point location as the structural model information of the building, comparing with a stored early warning parameter threshold or a threshold obtained by an early warning parameter threshold calculation method, then marking the coordinate measured value which is not smaller than the threshold as an early warning parameter, combining the marked early warning parameters, and finally, if the combined early warning parameter set contains any early warning parameter model, generating an alarm; meanwhile, the prior art can know that: when the radar probe is used, tracking measurement can be carried out only on the strongest point of signal reflection on the same radius in the local spherical transmitting domain, so that a signal enhancement reflection cone (radar beacon) is required to be arranged on the surface of a building, and the application number is as follows: CN201710377888.4 discloses a method for fixing a matched radar beacon on a building surface by means of transportation, magnetic attraction, impact, adhesion and the like; considering that the high temperature at the time of fire may interfere with electromagnetic waves (application number: CN 201720777637.0), the application number: CN201710893850.2, CN201710894123.8 respectively disclose calibration systems and methods for small horizontal and vertical displacement deformations for radar beacons;

D. Using photogrammetry techniques. Application number: CN200710303966.2 emphasizes that failure of the bottom column is judged by means of a photograph tracking the movement of the target point in the upper chamber of the ignition layer; application number: CN201611191037.2 emphasizes the comparison of the photographs of the building before fire (during the examination of fire protection of the building) and after fire occurrence, and judges whether the deformation is greater than the limit state of the bearing capacity, and also needs to set artificial marks on the elevation playing the role of bearing;

E. three-dimensional positioning monitoring system based on China Beidou satellite navigation system (BDS) and the United states Global Positioning System (GPS). Application number: CN201821985439.4 discloses a system for monitoring displacement of a building under fire, which aims at a high-rise building and is provided with a plurality of virtual displacement monitors in a deformable area of the high-rise building. Meanwhile, buildings such as high-rise buildings, power transmission towers, large-span space structures and the like are mentioned incidentally; in order to improve positioning accuracy, application number: CN201210398744.4 discloses methods for improving GPS positioning accuracy by some column coordinate transformations using local positioning information provided by mobile inertial navigation techniques or ad hoc networks, unlike Assisted Global Positioning Systems (AGPS) and Differential Global Positioning Systems (DGPS).

(2) Measurements are made for other physical characteristics.

A. For the vibration characteristics of building structures. Application number: CN201910566956.0 discloses a system and method for obtaining vibration acceleration signal by using acceleration sensor and analyzing frequency-time curve at PC terminal to perform collapse early warning on multi-layer steel frame structure building, the method uses the phenomenon that the (local) vibration frequency may be suddenly changed when the frame structure is near collapse under fire, but lacks feasibility in practical operation, and is represented in: the steel structure in the frame construction is not exposed, and the integrated magnetic base cannot be fixed on the surface of the steel structure in emergency; under the action of high temperature in fire, the magnetism of the magnetic seat is weakened, and the magnetic seat cannot be reliably fixed with a building structure; according to the characteristic of fire spread development, firefighters are difficult to find a position-fixed acceleration sensor near a fire source in high-temperature, dense smoke and dark environments; the internal wireless communication of the fire scene is unsmooth, which can directly lead to the failure of acquisition of acceleration signals; the analysis of the multiple frequency-time curves at multiple positions takes which curve is taken as a main reference, and the change of which curve belongs to the occurrence of 'sharp drop' of the frequency, so that the practical application of the technology is restricted; application number: CN200810064763.7 discloses a vibration monitoring system for building structure collapse in case of fire, which connects a vibration sensor to a building structure member;

B. Acoustic emission characteristics for building structures in fire. Application number: CN200810064762.2 discloses a monitoring system and method for analyzing acoustic emission parameters in the case of fire of a building structure, establishing a relationship with the fracture and stability of building structural members, and further judging whether the structure is in a safe state, and focusing on the relationship between the destabilization mode of the concrete structure and the simultaneous acoustic emission.

Summarizing the above related art, it can be found that:

1. in the aspect of predicting collapse accidents of fire buildings, the prior art focuses on collapse (lateral deformation) of multi-layer and high-rise buildings, except for application numbers: CN201821985439.4 is incidentally mentioned, there is no early warning device and method for collapse of roof structure in large space (before collapse of roof structure, horizontal lateral deformation of peripheral wall is very small, and detection from peripheral elevation is difficult);

2. the prior art mainly aims at displacement (speed, acceleration), vibration characteristics and the like of buildings, and belongs to a bearing capacity method in fire disaster failure judgment. The critical temperature method for judging the fire resistance failure of the building structure, which is a temperature field near the roof and a temperature field in the roof structural member, has not been proposed by the corresponding application technology;

3. The prior art is aware of the importance of non-contact measurement, but means such as searching a fixed point on the building surface or arranging a standard point (when a laser total station is used), installing a radar beacon (when a radar probe is used), arranging a wireless acceleration sensor with a magnetic base and the like are needed after the non-contact measurement reaches a fire scene. Both belonging to single point measurement, and being difficult to find key positions closely related to the initial collapse occurrence point. Even if the building is artificially divided into a plurality of areas, each area is monitored by a single point (application number: 201710378847.7), the single point cannot completely represent the deformation behavior of the area, and no calculation method for linking the single point into the area exists. In consideration of safety of rescue workers, the most critical fire areas cannot be arranged close to each other, and a collapse monitoring technology and a collapse monitoring method for a local area above a large-span roof combustion object and further for the whole roof cannot be realized at present, and the spreading condition of fire in a building cannot be mastered and judged;

4. the partial scheme is excessively complicated in the aspects of technical principle, erection and debugging, the number of the arranged detection devices and the field ascending condition are extremely high in challenges, the temporary and rapid mastering of effective information of a fire scene is not facilitated, and the feasibility is poor. For example, a radar probe is used for monitoring a fixed point of a wall surface, three radar devices are required to monitor the same radar beacon, three-way deformation coordinates of the fixed point can be obtained through calculation, and radar signals are easily interfered by a metal roof of a building, so that monitoring data are discontinuous.

Disclosure of Invention

In view of the state of the art and the shortcomings existing in the related art, the invention provides a realization method of a collapse early warning system under a large-space roof fire disaster.

The invention overcomes the defects in the prior art that: the device, the technology and the method adopted for solving the collapse early warning problem in the building fire accident focus on the collapse (mainly horizontal inclined deformation) of the multi-layer and high-rise building under the fire disaster, but the collapse (mainly deflection deformation) of the roof structure with large plane occupation under the fire disaster, which is not the roof of a large space place, is difficult to observe around the ground, and the collapse development process of the large-span roof structure is difficult to capture and determine the deformation process and the magnitude by the currently adopted method for observing the lateral deformation of the supporting wall body around the building. The principle of solving the technical index detected by the collapse of the building is all attributed to the fire-resistant bearing capacity of the building structure under the fire, namely the method of passing the bearing capacity, and the technology and the method of directly passing the critical temperature method of the structural member of the roof do not exist. The adopted instrument device belongs to non-contact measurement and also needs to be a necessary surface mounting part of a fire building, and is characterized in that the instrument device still belongs to scattered single-point measurement, the key position reflecting the collapse deformation development of the area is difficult to directly find, a method for calculating the deformation of the key area according to the single point is not available, so that scattered individual monitoring points are not necessarily represented, the high-temperature danger of the key area, personnel cannot approach to the installation and cannot detect the passive current situation, and meanwhile, the technology and the method for monitoring the local area above the large-span roof combustion object and then reaching the whole roof are not available, and the fire development condition inside the building cannot be obtained in a three-dimensional manner. The partial scheme is too complicated, a plurality of instruments and equipment can only monitor one point, the layout quantity is large, the site condition requirement is high, the construction structure deformation effective information is not easy to grasp on site rapidly, no alternative scheme exists when signals are interfered, and key information interruption is easy to cause.

The invention can realize the whole process monitoring and early warning of collapse of the roof structure in large space places from two angles of a critical temperature method and a bearing capacity method, and the provided technical scheme supplements each other, and also in the category of non-contact measurement, the whole process monitoring of the area of the roof structure seriously affected by fire in large space places can be realized by arranging three detection points relatively far away from the center of a combustion area on a roof by roof breaking staff or a projection means, so that the current situation that a plurality of devices can only monitor a single point which is uncertain and is not critical and can not monitor the area is changed, the internal temperature field of the roof structure member can be obtained, the development and the estimation of the fire development in the building can be assisted, the current focused scattered point detection is developed to the area detection and the behavior estimation are further obtained, the deformation of the whole roof structure is obtained, meanwhile, the operation method of the fire extinguishing site is complied, the safety of operators is emphasized, the backup path is provided for key information transmission, and the reliability and the maneuvering reaction capacity is increased.

The implementation method of the collapse early warning system under the fire disaster of the roof structure in the large space place, which is obtained by the technical scheme, can be applied to the collapse early warning under the fire disaster of the roof structure in the building with the large space place such as factory buildings, warehouses and the like, can also be used for multi-story high-rise buildings, tower mast structures, high-rise structures and the like, increases scientificity and safety by taking critical temperature and bearing capacity deformation characteristics as judgment standards, increases reliability by taking wireless and sound emission as transmission modes, avoids key information omission from single-point detection innovation to the critical area of the roof to integral area prediction, is convenient to arrange and simple to debug, pays attention to safety of operators, and provides powerful software and hardware support for emergency treatment of collapse accidents of the building fire disaster.

The technical scheme adopted by the invention for achieving the purpose is as follows: the implementation method of the collapse early warning system under the fire disaster of the large-space roof is characterized in that the early warning system comprises a detection part and a disposal part;

the detection part is arranged on a roof corresponding to the roof structure grid to be detected, obtains the dynamic temperature and dynamic space coordinates of the near-roof of the detected point position, transmits data to the outside in a wireless and acoustic emission mode, and immediately sends out visual early warning in an optical display mode;

the detection part is formed by sequentially connecting a roof perforation assembly, a temperature detection assembly, a hand-held installation assembly, a heat insulation buffer joint assembly, a heat insulation shock absorption box, a light display elevation identification assisting assembly and a projection joint assembly in series;

the roof perforation assembly, the handheld installation assembly, the heat insulation buffer joint assembly and the projection joint assembly are used for penetrating and integrally installing and fixing the detection part on a roof corresponding to the grid of the roof structure, and the roof perforation assembly is used for perforating in the range of the roof corresponding to the grid in the installation process of the detection part; the hand-held installation assembly and the projection joint assembly are respectively used for installing the whole detection part in a manual and fixed-point projection mode; the heat insulation buffer joint component is used for buffering vibration of the whole heat insulation damping box and the light display elevation auxiliary identification component in the installation process of the detection part and reliably fixing the whole detection part on a roof corresponding to the structural grid of the roof;

The temperature detection component is used for monitoring the dynamic temperature of the near roof of the detected point location and storing the dynamic temperature by the data acquisition component in the heat insulation damping box;

the optical display Gao Chengchu identification component obtains dynamic space elevation coordinate data stored by the data acquisition component in the heat insulation shock absorption box and sends visual early warning to the outside in a color type and depth mode;

a system power supply assembly, a space positioning assembly, a data acquisition assembly, a data emission assembly and an acoustic emission elevation identification assisting assembly which are connected through a circuit are arranged in the heat insulation shock absorption box;

the heat insulation damping box is used for ensuring that the detection part is integrally installed in a system power supply assembly, a space positioning assembly, a data acquisition assembly, a data transmission assembly, a sound transmission elevation identification assisting assembly and an accessory wiring in the process of the roof corresponding to the structural grid of the roof to be protected from vibration damage and from high-temperature smoke damage overflowing the roof in the running process; the space positioning component is used for obtaining dynamic space coordinates of the detected point positions, comprises dynamic space elevation coordinate data and dynamic space horizontal coordinate data, and is stored by the data acquisition component; the data transmitting assembly obtains the dynamic temperature data and the dynamic space coordinate data of the near roof stored by the data collecting assembly and transmits the dynamic temperature data and the dynamic space coordinate data to the outside in a wireless mode; the acoustic emission elevation auxiliary recognition component obtains dynamic space elevation coordinate data stored by the data acquisition component and transmits the dynamic space elevation coordinate data to the outside in an acoustic emission mode;

The disposal part is arranged in a ground safety area around the fire building, receives dynamic temperature data and dynamic space coordinate data of the near-roof of the detection point sent by each detection part in a wireless and sound identification mode, combines manually input building and roof structure information data to perform calculation, sends out sound early warning to all personnel in the fire-fighting and rescue site according to different early warning levels, and sends out wireless early warning to fire-fighting and rescue personnel in a dangerous area in the building;

the processing part consists of a building and roof structure information input module, a rescue worker position dynamic acquisition module, a sound identification component, a data receiving component, a model algorithm module, an early warning grading module and an early warning sending module which are connected with the processing display, wherein the early warning sending module comprises a sound broadcasting component and a wireless broadcasting component;

the data receiving component is used for receiving the data transmitted by the data transmitting component of each detection part through wireless transmission and inputting the data into the processing display;

the sound recognition component is used for receiving data transmitted by the sound emission height recognition assisting component of each detection part through sound emission and inputting the data into the processing display; the building and roof structure information input module is used for manually inputting basic information of the occupied area, the space clearance, the roof structure, the type of the combustion objects and the ignition time in the ignition building which is obtained by a fire inspector through on-site investigation or according to data, and inputting the basic information into the processing display; the dynamic rescue personnel position acquisition module is connected with a wireless communication machine carried by each firefighting rescue personnel and is used for acquiring the dynamic spatial position of the firefighting rescue personnel in the fire building when the firefighting rescue personnel carry out the fire extinguishing operation and inputting the dynamic spatial position into the processing display machine;

The processing display machine calls a model algorithm module to realize that dynamic space elevation coordinate data of each detection point position received through the data receiving component and the sound recognition component are respectively screened and fitted into respective new dynamic space elevation coordinate data, so that iterative calculation of building and roof structure information, near-roof dynamic temperature of each detection point position and the new dynamic space coordinate data is realized, a serious affected area range of a roof corresponding to a firing combustion range in the building is obtained, and data information of temperature fields in roof structural members in the area and the position, the regional deformation development characteristics and the regional roof structural members in the area of the roof are positioned in the roof and output to an early warning classification module;

the processing display calls an early warning grading module, processes data information output by a model algorithm module, automatically determines early warning levels or early warning levels for executing manual input of fire scene rescue commanders from the aspects of the proportion and the position of the area occupied by the area range of the serious affected area of the roof, the proportion of the temperature field reaching the critical temperature in the structural member of the inner roof of the inner area, the expansion or collapse stage and the magnitude of the area deformation development, simultaneously processes the position data information of each firefighter acquired by a rescue personnel position dynamic acquisition module, and transmits early warning instructions to an early warning sending module after combining the position data information; the processing display can display the area range of the roof severely affected by fire, the position of the roof, the deformation development characteristics of the area, the temperature field value in the structural member of the roof in the area, the dynamic space position of fire rescue workers, the early warning level and the execution condition of early warning instructions in real time;

The early warning sending module receives the instruction of the early warning grading module, finally drives the sound broadcasting assembly to send out different-level sound early warning to all personnel in the fire-fighting rescue scene, and finally drives the wireless broadcasting assembly to send out different-level wireless early warning to fire-fighting rescue personnel in a dangerous area in the building;

the implementation method of the collapse early warning system under the fire disaster of the large-space roof comprises the following steps:

s1, after arriving at a fire building site, arranging a treatment part in a ground safety area around the fire building and supplying power to work;

s2, a fire inspector knows the basic information of the occupied area, the space clear height, the roof structure, the type of the combustion object and the fire moment in the fire large space building at the first time and inputs the basic information into the building and roof structure information input module;

s3, the roof breaking and disassembling personnel manually or in a ground fixed-point projection mode installs at least three detection parts on the roof corresponding to the roof structural grid and remotely controls the detection parts to start working after being in communication connection with the same treatment part, the detection parts are installed by taking care of avoiding damage and vibrating the roof main body bearing structure, the detection parts do not need to be close to the area of the roof severely affected by fire, and the installation quantity of the detection parts can be increased as necessary along with the spreading of indoor fire;

S4, a fire-fighting rescue worker entering the interior of the building and located at the periphery of the exterior of the building to carry out fire-extinguishing operation connects the portable wireless communication machine with the fire-fighting rescue worker position dynamic acquisition module and starts working;

s5, in the collapse early warning and monitoring process, monitoring and processing display information of a fire scene rescue commander, attention scene fire development condition information and information reported by a fire scene investigation staff in real time;

s6, an early warning grading module automatically determines early warning levels or carries out early warning levels manually input by fire scene rescue commanders in real time, and transmits early warning instructions to an early warning sending module by combining the processed position data information of the scene fire rescue workers;

s7, rescue workers around the outdoor of the fire-fighting rescue site building know deformation development characteristics of roof detection points through the optical display elevation identification assisting assembly, all the workers can hear early warning reminding sent by the sound broadcasting assembly, and fire-fighting rescue workers in a dangerous area in the building receive the early warning reminding sent by the wireless broadcasting assembly through a portable wireless communication machine;

and S8, finally, quickly evacuating relevant fire rescue workers threatened by the collapse risk of the building roof in the large space on fire to a safety area.

The beneficial effects of the invention are as follows: the implementation method of the collapse early warning system under the fire disaster of the large-space roof has the characteristics of strong pertinence to the prediction demand of collapse accidents under the fire disaster of the roof structure of the large-space place, compliance with the general disposal method of fire extinguishing and rescue operation (breaking, dismantling and smoke discharging of the roof) of the building, attention to the safety of roof operators, small use quantity of detection equipment (the requirement is met by three detection parts after the detection of the fire disaster), advanced and convenient arrangement, simple debugging, multiple paths of a transmission mode, abundant and reliable acquisition data, reasonable built-in module algorithm, automatic and scientific judgment indexes and consideration of experience judgment, and further expansion of application potential in other building types (high-rise structures, tower mast structures and multi-layer high-rise structure buildings).

The detection part has the capability of integrating installation and detection through the design of the roof perforation assembly, so that the inconvenience in operation caused by the scattering of articles carried by fire rescue workers is avoided;

the design of the handheld installation assembly or the projection joint assembly enables the detection part to be installed while the roof breaking, dismantling and smoke discharging are carried out on a large space place manually, and the projection mode conforms to the development trend of the current fire-fighting technology, such as ground emission installation and unmanned aerial vehicle throwing installation;

The circuit of the detection part is in a working state to be instructed when being arranged on a roof by the design of the system power supply assembly, so that the communication control of the treatment part can be responded in time;

the design of the temperature detection assembly enables the acquisition of a dynamic temperature field near the roof to be possible, further supports the calculation of the temperature field in the area, which is seriously affected by the fire, of the roof component, and enables the application of critical temperature to perform collapse early warning on the roof structure, and greatly increases the prediction precision;

the position of the severely affected area of the roof is calculated to be possible through the design of the space positioning assembly, the development of more three-dimensional investigation fire is assisted, and a foundation is provided for the calculation of the severely affected area of the roof and even the integral deformation of the roof;

the design of the acoustic emission elevation auxiliary recognition component and the acoustic recognition component makes up for the situation that the data transmission in a single way is possibly interrupted by accidental interference of the outside, can mutually prove with wireless transmission, and can supplement the interrupted part of the wireless transmission;

the dynamic space elevation coordinate data obtained by the detection part can be more directly focused by field personnel through the design of the light display elevation auxiliary recognition component, and the method is particularly suitable for safety observers such as the night to develop the condition of poor external investigation conditions, wherein the darker the color is used for representing the expansion stage of the roof, the faster the expansion rate of the color is, the yellow is used for representing the collapse stage of the roof, and the darker the yellow is collapsed and the faster the yellow is, visual and reasonable;

The division design of the model algorithm module and the early warning grading module makes the calculation and judgment function more clear, and is beneficial to the perfect development of the respective functions and the addition of manual operation. The model algorithm module realizes the requirements of calculating the range, the position, the deformation and the component temperature of the severely affected area of the roof by installing the detection part far away from the roof above the flame of the combustion object, so that the key detection area can be grasped and the safety of operators can be ensured;

through the design of the building and roof structure information input module, relevant parameters in the model algorithm module can be purposefully called while necessary calculation information is input, and the calculation result is more accurate and reliable;

in a word, the invention fills the blank that no system for warning the collapse accident of the roof structure in the large space place aims at the specific fire disaster, adopts the detection, calculation and early warning device and technology combining the bearing capacity method and the critical temperature method, changes the current situation that the key point cannot be determined in the current single-point detection and the area seriously affected by the fire disaster cannot be monitored, greatly reduces the use quantity and saves the time of the fire scene compared with the traditional early warning instrument erection scheme, and has huge application prospect in the treatment of the emergency rescue accident of the fire disaster and huge social public safety benefit.

Drawings

FIG. 1 is a schematic diagram of the connection of the early warning system of the present invention;

fig. 2 is a schematic diagram of an embodiment of the collapse early warning system according to the present invention using three detection units.

Detailed Description

As shown in fig. 1-2, a method for realizing a collapse early warning system under a large-space roof fire disaster is provided, wherein the early warning system comprises a detection part and a disposal part;

the detection part is arranged on a roof corresponding to the roof structure grid to be detected, obtains the dynamic temperature and the dynamic space coordinates of the near-roof of the detected point position, transmits data to the outside in a wireless and acoustic emission mode, and immediately sends out visual early warning in an optical display mode;

the detection part is formed by sequentially connecting a roof perforation assembly, a temperature detection assembly, a handheld installation assembly, a heat insulation buffer joint assembly, a heat insulation shock absorption box, a light display elevation identification assisting assembly and a projection joint assembly in series;

the roof perforation assembly, the hand-held installation assembly, the heat insulation buffer joint assembly and the projection joint assembly are used for penetrating and integrally installing and fixing the detection part on a roof corresponding to the structural grid of the roof; the roof perforation assembly is used for perforating holes in the roof range corresponding to the grid in the installation process of the detection part; the hand-held installation assembly and the projection joint assembly are respectively used for installing the whole detection part in a manual and fixed-point projection mode; the heat insulation buffer joint component is used for buffering vibration of the whole heat insulation damping box and the light display elevation auxiliary identification component in the installation process of the detection part and reliably fixing the whole detection part on a roof corresponding to the structural grid of the roof;

the heat insulation damping box is used for ensuring that the detection part is integrally installed in a system power supply assembly, a space positioning assembly, a data acquisition assembly, a data transmission assembly, a sound transmission elevation identification assisting assembly and an accessory wiring in the process of the roof corresponding to the structural grid of the roof to be protected from vibration damage and from high-temperature smoke damage overflowing the roof in the running process;

the space positioning component is used for obtaining dynamic space coordinates of the detected point positions, comprises dynamic space elevation coordinate data and dynamic space horizontal coordinate data, and is stored by the data acquisition component; the data transmitting assembly obtains the dynamic temperature data and the dynamic space coordinate data of the near roof stored by the data collecting assembly and transmits the dynamic temperature data and the dynamic space coordinate data to the outside in a wireless mode; the acoustic emission elevation auxiliary recognition component obtains dynamic space elevation coordinate data stored by the data acquisition component and transmits the dynamic space elevation coordinate data to the outside in an acoustic emission mode;

The disposal part is arranged in a ground safety area around the fire building, receives dynamic temperature data and dynamic space coordinate data of the near-roof of the detection point positions sent by the detection parts in a wireless and sound identification mode, combines manually input building and roof structure information data to perform calculation, sends out sound early warning to all personnel in the fire-fighting and rescue site according to different early warning levels, and sends out wireless early warning to fire-fighting and rescue personnel in a dangerous area in the building;

the disposal part consists of a building and roof structure information input module, a rescue personnel position dynamic acquisition module, a sound identification module, a data receiving module, a model algorithm module, an early warning grading module and an early warning sending module which are connected with the processing display, wherein the early warning sending module comprises a sound broadcasting module and a wireless broadcasting module;

the sound recognition component is used for receiving the data transmitted by the sound emission height auxiliary recognition component of each detection part through sound emission and inputting the data into the processing display; the building and roof structure information input module is used for manually inputting basic information such as the occupied area, the space clearance, the roof structure, the type of combustion objects, the fire time and the like in the fire building which is obtained by a fire inspector through on-site investigation or according to data, and inputting the basic information into the processing display; the dynamic rescue personnel position acquisition module is connected with a wireless communication machine carried by each firefighting rescue personnel and is used for acquiring the dynamic spatial position of the firefighting rescue personnel in the fire building when the firefighting rescue personnel carry out the fire extinguishing operation and inputting the dynamic spatial position into the processing display machine;

the processing display calls an early warning grading module, processes data information output by a model algorithm module, automatically determines early warning levels or early warning levels for executing manual input of fire scene rescue commanders from the aspects of the proportion and the position of the area occupied by the area range of the serious affected area of the roof, the proportion of the temperature field reaching the critical temperature in the structural member of the inner roof of the inner area, the expansion or collapse stage and the magnitude of the area deformation development, simultaneously processes the position data information of each firefighter acquired by a rescue personnel position dynamic acquisition module, and transmits early warning instructions to an early warning sending module after combining the position data information; the processing display can display the conditions of the area range of the serious fire affected by the roof, the position of the roof, the deformation development characteristics of the area, the numerical value of the temperature field in the structural member of the roof in the domain, the dynamic space position of the fire rescue personnel, the early warning level, the execution of early warning instructions and the like in real time;

The early warning sending module receives the instruction of the early warning grading module, finally drives the sound broadcasting assembly to send out different-level sound early warning to all people in the fire-fighting rescue scene, and finally drives the wireless broadcasting assembly to send out different-level wireless early warning to fire-fighting rescue workers in a dangerous area in the building.

s2, a fire inspector knows basic information such as the occupied area, the net height, the roof structure, the type of the combustion object, the fire moment and the like in the fire large-space building at the first time and inputs the basic information to a building and roof structure information input module;

s3, the roof breaking and disassembling personnel manually or in a ground fixed-point projection mode installs at least three detection parts on the roof corresponding to the roof structural grid and remotely controls the detection parts to start working after being in communication connection with the same treatment part, the detection parts are installed by taking care of avoiding damaging and vibrating the weighing structure of the roof main body, the detection parts do not need to be close to the area of the roof severely affected by fire, and the installation quantity of the detection parts can be increased as necessary along with the spreading of indoor fire;

s6, an early warning grading module automatically determines early warning levels or performs early warning levels manually input by fire scene rescue commanders in real time and transmits early warning instructions to an early warning sending module by combining the processed position data information of the scene fire rescue workers;

The model algorithm module respectively removes coordinate data with unreasonable numerical oscillation at a certain moment from dynamic space elevation coordinate data received by each detection point through the data receiving component and the sound recognition component, then carries out fitting processing of connection at the front moment and the rear moment, and takes the average value of two elevation coordinate-time curves as new dynamic space elevation coordinate data; when the dynamic space elevation coordinate data of each detection point is interfered by the outside of the fire scene and cannot be continuously received through the data receiving component or the sound recognition component, the coordinate data which is unreasonable in numerical oscillation at a certain moment is removed from the part by using the part of the coordinate data received by the single component in the interfered time period, then fitting processing of connection at the front and rear moments is carried out, and the data processing method of the non-interfered time period is the same as the front and is integrally used as new dynamic space elevation coordinate data;

the model algorithm module establishes a relationship between the range of the severely affected area of the roof and the heat release rate Q of the combustion products through a formula (1):

A _q ＝Q/q (1)

wherein A is _q Q is an input parameter related to the type of combustion species and the like for the range of the severely affected area of the roof;

the model algorithm module further establishes a relationship between the boundary temperature of the severely affected area of the roof and the heat release rate Q of the combustion products through the formula (2):

Wherein A is _sp The method comprises the steps that (1) the occupied area of the interior of an input fire building is input, H is the space clear height, and χ is the input adjustment coefficient considering the roof structure;

the model algorithm module further establishes the position relation between the detection point and the boundary of the severe affected area of the roof through a formula (3):

where η is the input attenuation coefficient related to the roof construction, μ is the input attenuation rate coefficient related to the roof construction, T _tx For the dynamic temperature of the near roof at the detection point where the detection part is positioned, x is the radial distance between the center of the severely affected area of the roof and the detection point;

adopting a trial-and-calculation iterative method, assuming different heat release rates Q of the combustion products, and combining the dynamic temperature T of the near roof at the detection point of the detection part _tx The radial distance x between the center of the severely affected area of the roof and the detection point is calculated according to the dynamic space horizontal coordinate data at the detection point, so that the range of the severely affected area of the roof and the position of the severely affected area of the roof can be determined in real time;

the model algorithm module calculates deformation development of the severe affected area of the roof at an expansion or collapse stage and magnitude according to radial distance x' between the detection point and the edge of the severe affected area of the roof and new dynamic space elevation coordinate data of the detection point, and calculates deformation development condition of the whole roof by combining input roof structure information;

The model algorithm module calculates the internal temperature field of the roof metal member by referring to the relevant regulations in GB 51249 through the input roof structure information and the fire time.

The early warning grading module automatically determines a slight early warning grade index that the proportion of the area of the serious affected area of the roof to the area of the roof is not more than 5 percent, the temperature field in the roof component in the non-area reaches the critical temperature, the area deformation development is still in an expansion stage, and the deformation value relative to the initial position is in millimeter level; the automatically determined serious early warning level index is any one of the three that the proportion of the area of the serious affected area of the roof to the area of the roof is not less than 10 percent, the proportion of the temperature field in the roof component to the critical temperature is not less than 10 percent or the area deformation development is changed from expansion to collapse; the general early warning level is between the slight early warning level and the serious early warning level, and is comprehensively judged by a fire scene rescue commander according to the display information of the processing display, the on-site fire development condition information and the information reported by the fire inspector in real time, and the information is manually input into the early warning grading module for execution.

The model algorithm module also includes a general fast modeling module and a finite element analysis module.

Example 1

s2, a fire inspector first time knows that the internal occupied area A of the fire oil drum storage and amplification space warehouse _sp ＝575m ² The building plane is rectangular, two rolling doors are obliquely arranged in opposite directions in the north and south directions, the south is completely opened, the clear height H=6.5 m of the flat roof space is achieved, the roof is formed by covering Bao Tiepi watts of aluminum silicate cotton sandwich plates, the roof structure is a flat rectangular pyramid grid structure, the surface of a rod piece is coated with 25mm thick fireproof paint according to the design, the fire starting time is about 11min before, the fire starting position is approximately positioned on the side of the center of the ground in the building, and the fire starting q of a plurality of oil storage barrels with the combustion objects arranged at fixed intervals is approximately equal to 2.5MW/m ² The detection information is input to a building and roof structure information input module;

s3, two persons responsible for roof breaking and disassembling respectively hold one detection part from the northwest corner (S _1x ) Southeast corner (S) _2x ) The outer wall maintenance ladder is arranged on the roof. Aluminum silicate cotton core-retaining iron in connecting line of square pyramid grid of each grid and 4 supporting points of roofPi Wumian the probe is held by piercing the roof panel with its roof piercing assembly and is integrally secured to the roof with a thermal insulation buffer joint assembly after insertion. Another person responsible for roof breaking holds a detection part from southwest corner (S _3x ) The process of installing and fixing the above detecting part on the roof is repeated by lifting the vehicle in a herringbone manner on the roof, see fig. 2. After the installation, the personnel quickly withdraw from the roof to the ground safety area. The treatment part of S1 receives the signals sent by the three detection parts and carries out communication connection, and the signals are remotely controlled to start working;

s4, connecting a portable wireless communication machine with a fire-fighting rescue personnel position dynamic acquisition module of a disposal part by 3 fire-fighting rescue personnel ready to enter the building and 2 fire-fighting rescue personnel ready to be positioned outside a rolling shutter door around the building to monitor fire-fighting operation, and then enabling the wireless communication machine to reach respective division positions to start working;

and S5, monitoring and processing display information of a display by a fire scene rescue commander in the collapse early warning and monitoring process. The field feedback of the rolling door is that a plurality of oil storage barrels placed in a single area at present are all on fire, and the fire is large and the combustion is relatively stable.

S6, taking the processing procedure of the 125 th operation of the early warning system as an example: referring to fig. 2, the processing display now receives the northwest angle from the data receiving assembly (S _1x ) Southeast corner (S) _2x ) Southwest corner (S) _3x ) Is the detected point temperature T of (2) _1x ＝400℃、T _2x ＝200℃、T _3x =350 ℃ and corresponding spatial horizontal coordinate data. The processing display calls a model algorithm module, and the data receiving component and the sound recognition component input the detection point position space elevation coordinate data of the processing display at the moment are subjected to mean value processing and relative initial deformation is obtained: h is a _1x ≈+3.5mm、h _2x ≈+2.4mm、h _3x ≈+3.2mm。

The processing display machine calls a model algorithm module to run trial calculation iteration of the heat release rate Q of the combustion object, the range is from 10MW to 40MW, the iteration interval is 1MW, and the Q is approximately equal to 25MW after the time is 0.01s for cyclic solution according to formulas 1 to 3. Corresponding to the determined area range A of the serious affected area of the roof _q ≈10m ² (equation 1), edge temperature(equation 2), S _1x Distance d from center of combustion object _1x Approximately 7.8m, likewise d _3x ≈9.0m、d _2x Approximately 13.5m (equation 3), the center of the severely affected area of the roof is determined to be located 4.8m further to the center of the roof and 1.6m further to the north at this point;

A _q =q/Q (formula 1)

The processing display machine calls a model algorithm module to linearly calculate that the deformation development of the severe affected area of the roof is still in an expansion stage and the average value of the edge expansion amount is h according to the new space elevation coordinate data of the three detection parts at the moment _e Approximately equal to +6.8mm, and the central expansion value is h _c The method comprises the steps of (1) calculating a roof structure model established by a rapid modeling module by adopting a finite element analysis module at the same time, and performing real-time comparison verification;

the processing display calls a model algorithm module according to the time t at the moment _al Approximately 785s (since fire), the maximum roof truss rod temperature is calculated with reference to the relevant specifications in GB51249 (equation 4)The temperature of the steel member is continuously reduced along with the increase of the distance between the horizontal direction in the roof and the center line of the combustion object (the center line of the fire source);

The model algorithm module outputs the calculation result at the moment to the early warning grading module;

and S7, the processing display calls the early warning grading module to process the instant data information output by the model algorithm module, and the early warning level at the moment is automatically determined to be a slight early warning level. The early warning grading module processes the position data information of the on-site rescue workers at the moment, transmits an early warning instruction to the early warning sending module to wirelessly remind 3 fire rescue workers entering the building of closely paying attention to the development of fire, and can carry out fire extinguishing operation in a short distance;

s8, 2 firefighters who monitor the fire extinguishing operation outside the outdoor peripheral rolling shutter door of the building know that the deformation development of the roof detection point position close to the firefighters is still in an expansion stage through red display of the light display elevation auxiliary identification component; 3 fire rescue workers in the building receive the early warning prompt sent by the wireless broadcasting component driven by the early warning sending module through the portable wireless communication machine, namely, the fire development is closely focused, and the fire extinguishing operation can be carried out in a short distance;

s9, repeating the processes of S6 to S8 at the frequency of 1Hz for each subsequent moment. S7, automatically judging the early warning level according to the frequency, or executing the early warning level manually input by a fire scene rescue commander, and transmitting an early warning instruction to an early warning sending module only when necessary;

S10, when indoor and outdoor firefighting rescue workers hear the sound broadcasting assembly and the serious early warning level prompt sent by the wireless broadcasting assembly is received by the wireless communication machine, the situation that the indoor firefighting rescue workers are threatened by collapse risk of a roof grid structure is indicated, and related workers should be evacuated to a safety area rapidly. The light at this point shows a yellow display of the elevation aid component and the color has darkened.

And S11, after the fire extinguishment rescue is finished, the processing display machine stores data, then the power supply of the treatment part is cut off, the fire scene is cleaned, and the detection part is recovered.

Claims

1. The implementation method of the collapse early warning system under the fire disaster of the large-space roof is characterized in that the early warning system comprises a detection part and a disposal part;

The roof perforation assembly, the handheld installation assembly, the heat insulation buffer joint assembly and the projection joint assembly are used for penetrating and integrally installing and fixing the detection part on a roof corresponding to the structural grid of the roof; the roof perforation assembly is used for perforating holes in the roof range corresponding to the grid in the installation process of the detection part; the hand-held installation assembly and the projection joint assembly are respectively used for installing the whole detection part in a manual and fixed-point projection mode; the heat insulation buffer joint component is used for buffering vibration of the whole heat insulation damping box and the light display elevation auxiliary identification component in the installation process of the detection part and reliably fixing the whole detection part on a roof corresponding to the structural grid of the roof;

2. The method for realizing the collapse early warning system under the fire disaster of the large-space roof according to claim 1, wherein the model algorithm module respectively removes coordinate data with unreasonable numerical oscillation at a certain moment from dynamic space elevation coordinate data received by each detection point through the data receiving component and the sound recognition component, performs fitting processing of connection at the front moment and the rear moment, and takes the average value of two elevation coordinate-time curves as new dynamic space elevation coordinate data; when the dynamic space elevation coordinate data of each detection point is interfered by the outside of the fire scene and cannot be continuously received through the data receiving component or the sound recognition component, the coordinate data which is unreasonable in numerical oscillation at a certain moment is removed from the part by using the part of coordinate data received by a single component in the interfered time period, and then fitting processing of connection at the front and rear moments is carried out, wherein the data processing method of the non-interfered time period is the same as the front and is integrally used as new dynamic space elevation coordinate data;

A _q ＝Q/q (1)

wherein A is _q Q is an input parameter related to the type of combustion species for the range of the severely affected area of the roof;

wherein A is _sp For the input floor space of the interior of the fire building, H is the spatial clearance, χ is the input adjustment factor for the roof construction considered, a ₁ 、a ₂ 、a ₃ 、b ₁ 、b ₂ 、b ₃ Fitting coefficients of the formula (2);

The model algorithm module calculates the internal temperature field of the roof metal component according to a formula (4) by referring to the relevant regulations in GB 51249 through the input roof structure information and the fire time,

wherein DeltaT _s The temperature rise of the steel member in time (t, t+delta t) is given in DEG C; t is the duration of the fire in s; Δt is a time step, the unit is s, and the value is not more than 5s; t (T) _s 、T _g The internal temperature of the steel member at the time t and the average temperature of hot flue gas are respectively shown in the unit of DEG C; ρ _s 、c _s The density of the steel materials is kg/m ³ And specific heat in J/(kg. Deg.C); f (F) _i V is the cross-sectional shape factor of the steel member with or without fire protection, in m ^-1 ；F _i To protect steel members against fires of unit length with or without fire protectionSurface area in m ² The method comprises the steps of carrying out a first treatment on the surface of the V volume of steel member in unit length, unit is m ³ The method comprises the steps of carrying out a first treatment on the surface of the Alpha is the integrated heat transfer coefficient, and the unit is W/(m) ² ·℃)。

3. The method for implementing a collapse warning system under a large-space roof fire disaster according to claim 1, wherein the warning classification module automatically determines a slight warning level index that the proportion of the area coverage of a severely affected area of a roof to the area of the roof is not more than 5%, the temperature field in a non-area roof member reaches a critical temperature, the area deformation development is still in an expansion stage, and the deformation value relative to an initial position is in millimeter level; the automatically determined serious early warning level index is any one of the three that the proportion of the area of the serious affected area of the roof to the area of the roof is not less than 10 percent, the proportion of the temperature field in the roof component to the critical temperature is not less than 10 percent or the area deformation development is changed from expansion to collapse; the general early warning level is between the slight early warning level and the serious early warning level, and is comprehensively judged by a fire scene rescue commander according to the display information of the processing display, the on-site fire development condition information and the information reported by the fire inspector in real time, and the information is manually input into the early warning grading module for execution.

4. The implementation method of the collapse early warning system under the fire disaster of the large-space roof according to claim 1, which is characterized in that: the model algorithm module also comprises a general rapid modeling module and a finite element analysis module.