CN-121617190-B - Comprehensive linkage alarm system for fire hidden danger and structural instability of wooden building

CN121617190BCN 121617190 BCN121617190 BCN 121617190BCN-121617190-B

Abstract

The invention discloses a comprehensive linkage alarm system for hidden fire hazards and structural instability of a wooden structure, which relates to the technical field of wooden structure safety monitoring and comprises a multidimensional heterogeneous signal acquisition module, a detection module and a detection module, wherein the multidimensional heterogeneous signal acquisition module is used for acquiring data and constructing a real-time state monitoring data set; the system comprises a structural spectrum reference modeling module, a thermal-frequency correlation analysis module, a structural state judging module, a cascade dynamic response module and an adaptive feedback correction module, wherein the structural spectrum reference modeling module is used for constructing a thermal-stiffness attenuation theoretical model, the thermal-frequency correlation analysis module is used for generating a thermal-frequency deviation index, the structural state judging module is used for identifying a pyrolysis state of wood and a structural instability risk, the cascade dynamic response module is used for executing corresponding fixed-point spray control, evacuation path planning and alarm output, and the adaptive feedback correction module is used for warehousing data and correcting thermosensitive ageing parameters. According to the invention, by fusing thermal imaging and vibration data, a thermal and rigidity correlation model is established, environmental wind load noise is effectively removed, accurate identification of hidden danger in a wooden building is realized, and building monitoring accuracy and emergency response efficiency are improved.

Inventors

CHEN WEIMEI
WANG FENG
LIN WENQI
LUO FURONG

Assignees

阳光学院

Dates

Publication Date: 20260512
Application Date: 20260203

Claims (6)

1. Comprehensive linkage alarm system of fire hazard and structure unstability is built to timber, its characterized in that includes: the multi-dimensional heterogeneous signal acquisition module is configured to acquire surface thermal imaging temperature field data, structural vibration response data and environmental parameters of a target wood structure building, and align time stamps to construct a real-time state monitoring data set; The structural spectrum reference modeling module is configured to establish a structural spectrum reference line based on modal scanning data and construct a thermal-stiffness attenuation theoretical model describing a nonlinear mapping relation between a temperature variable and an elastic modulus by combining with a wood pyrolysis kinetic parameter; The thermal-frequency correlation analysis module is configured to calculate correlation characteristics between the temperature time change rate and the natural frequency change rate and generate a thermal-frequency deviation index; The structural state judging module is configured to identify the pyrolysis state of the wood and the structural instability risk based on the residual analysis result of the thermal-frequency deviation index and the thermal-stiffness attenuation theoretical model; The grading linkage response module is configured to execute corresponding fixed-point spray control, evacuation path planning and alarm output according to the identified state grade; The self-adaptive feedback correction module is configured to store temperature change data and frequency change data in the event process into a database and correct the thermosensitive aging parameters in the thermal-stiffness attenuation theoretical model; the modules are realized by the following method: S1, acquiring surface thermal imaging temperature field data, structural vibration response data and environmental parameters of a target wood structure building, and constructing a real-time state monitoring data set; S2, carrying out modal scanning on a target wood building, establishing a structural spectrum datum line at normal temperature, presetting a thermal-stiffness attenuation theoretical model, and defining a functional relation of elastic modulus attenuation caused by temperature change; s3, monitoring surface thermal imaging temperature field data and structural vibration response data in real time, and activating a high-frequency sampling mode when detecting that local temperature exceeds a preset safety value or natural frequency is subjected to aperiodic attenuation; s4, extracting temperature gradient characteristics and frequency change acceleration characteristics in a high-frequency sampling mode, calculating a heat-frequency deviation degree, inputting the heat-frequency deviation degree into a heat-rigidity attenuation theoretical model for residual analysis, and generating a confidence degree evaluation result of the influence of a fire source on the structure; S5, judging fire hidden danger levels and a structural instability time window based on a confidence evaluation result of the structural influence of the fire source and the attenuation amount of the current structural frequency relative to the datum line, and outputting a grading alarm instruction and a control signal; S6, responding to the hierarchical alarm instruction, executing corresponding physical intervention measures, feeding back heterogeneous data of the current monitoring period to the structural spectrum reference modeling module, and updating the thermosensitive aging parameters; S2 specifically comprises: S21, in the system initialization stage, excitation is applied to a target wood building or environmental excitation is utilized, a structural response signal is collected, a multi-order natural frequency and damping ratio is extracted through fast Fourier transformation, and a structural spectrum datum line is constructed; s22, based on the wood material property, introducing a pyrolysis kinetic equation, establishing a nonlinear function relation between a temperature variable and an elastic modulus, and generating a thermal-stiffness attenuation theoretical curve; s23, calculating a first derivative of a thermal-stiffness attenuation theoretical curve, determining a theoretical frequency attenuation threshold corresponding to unit temperature rise, and taking the theoretical frequency attenuation threshold as a thermal-stiffness attenuation rate reference.
2. The comprehensive linkage alarm system for building fire hazards and structural instability of a wooden building according to claim 1, wherein S1 specifically comprises: Arranging an infrared thermal image sensing unit and a piezoelectric vibration sensing unit at key member nodes of a target wood structure building, and acquiring spatial position information of each node; in the sampling period, acquiring a surface temperature distribution matrix through an infrared thermal image sensing unit, and acquiring structural micro-vibration acceleration time sequence data through a piezoelectric vibration sensing unit; Acquiring environmental wind speed data and environmental humidity data as environmental noise references; and performing timestamp alignment and denoising treatment on the surface temperature distribution matrix, the structural micro-vibration acceleration time sequence data, the ambient wind speed data and the ambient humidity data, and combining to generate a real-time state monitoring data set.
3. The comprehensive linkage alarm system for building fire hazards and structural instability of a wooden building according to claim 2, wherein S4 specifically comprises: S41, calculating the temperature time change rate of a surface temperature distribution matrix based on data in a high-frequency sampling mode, and calculating the natural frequency change rate and the frequency change acceleration corresponding to the structural micro-vibration acceleration time sequence data; s42, filtering the environmental wind load interference by utilizing the frequency variation acceleration, removing the oscillation type frequency variation component, and reserving the monotonically attenuation type frequency variation component; S43, carrying out normalization processing on the reserved monotonic attenuation type frequency change component and the temperature time change rate, and calculating a cross-correlation coefficient of the monotonic attenuation type frequency change component and the temperature time change rate on a time axis; S44, substituting the normalized data into a thermal-stiffness attenuation theoretical model, and calculating a residual error value between the observed frequency attenuation rate and the attenuation rate predicted by the theoretical model; s45, generating a thermal-frequency deviation degree based on the cross-correlation coefficient and the residual value, if the cross-correlation coefficient is larger than a preset correlation threshold value and the residual value is smaller than a preset model tolerance, judging that the thermal-frequency deviation degree is high-confidence structural pyrolysis, and outputting the confidence degree of the fire source representing the possibility of damage of the structure and influencing the structure.
4. The comprehensive linkage alarm system for building fire hazards and structural instability of a wooden building according to claim 3, wherein S5 specifically comprises: S51, setting surface interference judgment logic, mechanical damage judgment logic and structure pyrolysis judgment logic; s52, if the temperature time change rate is higher than a preset temperature rise threshold value and the natural frequency change rate is lower than a preset frequency change threshold value, judging that the unstructured surface fire source is interfered; s53, if the natural frequency change rate is higher than a preset frequency change threshold value and the temperature time change rate is lower than a preset temperature rise threshold value, judging that the mechanical damage is not caused by fire; S54, if the confidence coefficient of the structural influence of the fire source meets the structural pyrolysis condition with high confidence coefficient, judging the structural fire hazard, and further calculating the total attenuation proportion of the current natural frequency relative to the structural spectrum datum line; S55, based on the total attenuation proportion, predicting a residual bearing life time window of the structure, and generating a comprehensive state evaluation result comprising hidden danger types, confidence coefficient and residual life.
5. The comprehensive linkage alarm system for building fire hazards and structural instability of a wooden building according to claim 4, wherein S6 specifically comprises: s61, receiving the comprehensive state evaluation result, and executing a grading strategy according to the risk grade; s62, if the structural fire hidden danger is judged and the instability threshold is not reached, performing a first-stage response, namely positioning the coordinate of a pyrolysis component, starting a fixed-point spraying device aiming at the coordinate of the component, and sending a smoldering early warning signal; S63, if the structure is about to be unstable or the total attenuation proportion exceeds a preset collapse threshold, executing a second-stage response, namely calculating the structural stability weight of each evacuation path node based on the predicted value of the residual life of the structure, planning an optimal evacuation path avoiding a high-risk beam column area, and controlling evacuation indicator lamps to dynamically display the path; s64, after the event is ended, extracting temperature-frequency evolution whole process data in the event, calibrating attenuation coefficients in a thermal-stiffness attenuation theoretical model by using the data, and updating thermosensitive aging parameters in a database.
6. The comprehensive linkage alarm system for building fire hazards and structural instability of a wooden building according to claim 5, wherein the specific steps of filtering the environmental wind load interference in S42 are as follows: Monitoring the time domain change characteristic of the natural frequency, calculating the difference between the natural frequency at the current moment and the natural frequency at the previous moment to obtain a frequency change amount, and if the frequency change amount shows the periodic fluctuation characteristic around the central frequency, marking the frequency change amount as elastic deformation caused by wind load or environmental vibration, and setting the frequency change amount to be zero; if the frequency variation presents an irreversible monotonic decreasing trend and the direction of the frequency variation acceleration is kept constant, the frequency variation is marked as plastic damage or pyrolysis softening caused by material stiffness degradation, and the frequency variation is reserved for subsequent analysis.

Description

Comprehensive linkage alarm system for fire hidden danger and structural instability of wooden building Technical Field The invention relates to the technical field of wood structure safety monitoring, in particular to a comprehensive linkage alarm system for hidden danger of fire disaster and structural instability of a wood structure. Background The wooden building is taken as a traditional building form, plays an important role in ancient building protection and modern green buildings, is mainly formed by combining wood members such as beams, columns and the like through mortise and tenon joint connection modes, has bearing capacity and fireproof performance directly related to the overall service life and use safety of the building, and generally needs to be subjected to daily inspection and monitoring of fire disaster prevention and structural health condition in daily use and maintenance processes in order to ensure the safety and durability of the building. In order to ensure safety, a plurality of sensors are usually required to be installed around key nodes and beams of the wooden building, state detection data of the wooden building are detected in real time through the sensors, and the aim of detection is to ensure safety of a building main body. In practice, however, there is a large noise in the detected data and some data that has little influence on the structural state. For example, wind load or accidental vibration of the external environment can cause vibration signals to be generated by the structure, but simple surface temperature monitoring is difficult to find slow hidden dangers occurring inside, if safety classification is directly carried out according to current detection data, the situation that the safety classification is inaccurate is easy to exist, and then larger hidden dangers exist. Disclosure of Invention The invention aims to provide a comprehensive linkage alarm system for fire hidden danger and structural instability of a wooden building, which solves the problems in the background technology. The invention provides a comprehensive linkage alarm system for fire hazard and structural instability of a wooden building, which comprises a multidimensional heterogeneous signal acquisition module, a detection module and a control module, wherein the multidimensional heterogeneous signal acquisition module is configured to acquire surface thermal imaging temperature field data, structural vibration response data and environmental parameters of a target wooden building and align time stamps to construct a real-time state monitoring data set; The structural spectrum reference modeling module is configured to establish a structural spectrum reference line based on modal scanning data and construct a thermal-stiffness attenuation theoretical model describing a nonlinear mapping relation between a temperature variable and an elastic modulus by combining with a wood pyrolysis kinetic parameter; The thermal-frequency correlation analysis module is configured to calculate correlation characteristics between the temperature time change rate and the natural frequency change rate and generate a thermal-frequency deviation index; The structural state judging module is configured to identify the pyrolysis state of the wood and the structural instability risk based on the residual analysis result of the thermal-frequency deviation index and the thermal-stiffness attenuation theoretical model; The grading linkage response module is configured to execute corresponding fixed-point spray control, evacuation path planning and alarm output according to the identified state grade; And the self-adaptive feedback correction module is configured to store temperature change data and frequency change data in the event process into a database and correct the thermosensitive aging parameters in the thermal-stiffness attenuation theoretical model. Preferably, the modules are realized by the following method: S1, acquiring surface thermal imaging temperature field data, structural vibration response data and environmental parameters of a target wood structure building, and constructing a real-time state monitoring data set; S2, carrying out modal scanning on a target wood building, establishing a structural spectrum datum line at normal temperature, presetting a thermal-stiffness attenuation theoretical model, and defining a functional relation of elastic modulus attenuation caused by temperature change; s3, monitoring surface thermal imaging temperature field data and structural vibration response data in real time, and activating a high-frequency sampling mode when detecting that local temperature exceeds a preset safety value or natural frequency is subjected to aperiodic attenuation; s4, extracting temperature gradient characteristics and frequency change acceleration characteristics in a high-frequency sampling mode, calculating a heat-frequency deviation degree, inputting the heat-frequency deviation