China Safety Science Journal

Influence mechanism of construction workers' emergency behavior

LI Yan, MAO Yu, ZHANG Yan

2021, 31(10): 1-7. doi:10.16265/j.cnki.issn1003-3033.2021.10.001

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In order to explore emergency behaviors of construction workers under engineering emergencies and improve efficiency of emergency management. Firstly, based on risk perception emotion model and SOR theoretical model, theoretical hypothesis model of risk perception and emotion on emergency behavior was constructed, and mediating effect of emergency awareness was tested, theoretical model was tested empirically through structural equation model(SEM) and Bootstrap method. The research results show that construction workers' risk perception and emotion have a significant two-way relationship. Risk perception and emotion have a significant positive impact on their emergency behavior. Emergency awareness has a significant mediating effect between risk perception and emotion and emergency behavior.

Risk prevention and governance path of highly aggregated tourist crowds in post-COVID-19 period

YIN Jie, CHENG Yun, ZHENG Xiangmin

2021, 31(10): 8-15. doi:10.16265/j.cnki.issn1003-3033.2021.10.002

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In order to explore risk prevention and governance path of highly aggregated tourist crowds, 495 incidents of highly aggregated tourist crowds from 2013 to 2019 were selected to analyze temporal and spatial characteristics for putting forward risk prevention logic and governance path with help of ArcGIS10.3. The results show that February, April, May, August and October were high risk months. Additionally, National Day golden week and Spring Festival were high risk period. High risk areas show characteristics of concentrated and contiguous expansion. It is suggested to form risk prevention logic of normalized, phased and focused risk prevention, form risk prevention logic of global, linkage and differential risk prevention, pay attention to strengthen ability of risk prevention, improve intensity of monitoring and early warning, building a comprehensive management system and strengthen ability of adjustment after the event.

Research on safety & security identity mechanism

WANG Bing, WANG Yuanjie, ZHANG Yalei, WU Chao

2021, 31(10): 16-22. doi:10.16265/j.cnki.issn1003-3033.2021.10.003

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In order to clarify safety & security identity law, carry out the theoretical level of safety & security identity mechanism research. Firstly, subject, object and mediator of safety & security identity were defined, and influencing factors of safety & security identity were analyzed. Then, mechanism of individual safety & security identity was analyzed, and circular model of individual safety & security identity was constructed and analyzed. Finally, mechanism of organizational safety & security identity was analyzed, and three-dimensional model for safety & security identity promotion in the organization was built and analyzed. The results show that process of individual safety & security identity is “safety & security learning→safety & security trust→safety & security willingness→safety & security compromise→safety & security support→safety & security effort”, organizational safety & security identity should be promoted from three aspects, namely promotion of safety & security identity subject, optimization of safety & security identity mediator, and perfection of safety & security identity object.

Study on parametric coupling characteristics of anti-impact two-stage safety valve for hydraulic supports

WANG Hui, ZHOU Guoqiang, SONG yuning, ZHAO Guochao

2021, 31(10): 23-31. doi:10.16265/j.cnki.issn1003-3033.2021.10.004

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As safety valve is an important protection component of hydraulic supports, in order to improve impact resistance of the latter, a two-stage safety valve with a rated pressure of 50 MPa and a flow of 1 000 L/min was proposed, before a mathematical model of the valve was established. Then, coupling effects of structural parameters, such as cross-sectional area of secondary inlet, secondary differential area, stiffness and pre-compression of external spring and others, on the valve's dynamic characteristics were studied through Matlab numerical simulation, and the best matching parameters were obtained. Finally, a dynamic impact test platform was established to test and verify its dynamic features. The results show that when two-stage differential area decreases, and outer spring's stiffness increases, the pressure overshoot, pressure stabilization time and unloading time of the two-stage safety valve are all reduced. The best matching parameters come as 863 mm² for a second-stage differential area and 119 286 N/m for outer spring stiffness, while the pressure and flow stability values are 49.2 MPa and 1 050 L/min, respectively, and the unloading time is 0.02 s. Moreover, simulation and test results are generally consistent.

Safety analysis on tower crane installation and dismantling

ZHAO Tingsheng, HU Junjie, SHI Yudong, JIANG Wenxi

2021, 31(10): 32-38. doi:10.16265/j.cnki.issn1003-3033.2021.10.005

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In order to improve safety management level of tower crane installation and dismantling operation in construction, STAMP method was used to establish a model of such operation. Then, STPA method was adopted to analyze the model's safety from three aspects, namely component failure, interaction between components and external influence of the system, and 60 hazards were obtained and divided into 15 items of 6 aspects, including documents, personnel, mechanical equipment, management, external environment and process. Based on this, accident causes in 70 reports of tower crane installation and dismantling accidents were classified and analyzed. The results show that the hazards that should be paid attention to in safety management of tower crane installation and dismantling operation include lack of on-site supervisors or their neglect of duties, operation without license, lack of or unreasonable operation scheme, insufficient safety training and technical disclosure and incorrect process execution.

Risk assessment model of aircraft opposite taxiing conflict

KANG Rui, YANG Kai

2021, 31(10): 39-45. doi:10.16265/j.cnki.issn1003-3033.2021.10.006

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In order to ensure safety of airport operation and detect opposite conflict behavior in time, an assessment model of opposite taxiing conflict was proposed. Airport operation procedure and dynamic taxiing process were abstracted, and conflict areas were defined with an integrated consideration of taxi section, jet range and other factors. Then, conflict risks were quantified and simulated based on real-time speed and distance. The results show that this model could quantitatively assess conflict risk of aircraft at both uniform and variable speed with head-to-head motion trend, and its risk value is proportional to length of opposite taxiing section, and inversely proportional to difference of aircraft's velocity and position. It is found that the model can predict conflict trend in advance which proves to be consistent with actual situation.

Synergistic effect of tungsten tailing filler in intumescent fire-retardant coatings

WANG Feiyue, LIU Hui, YAN Long

2021, 31(10): 46-53. doi:10.16265/j.cnki.issn1003-3033.2021.10.007

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In order to reuse tungsten tailing, TTF was prepared through washing, pulverizing and surface modification processes, and applied in intumescent fire-retardant coatings. Then, flame retardancy and smoke suppression properties of TTF were studied by using big panel method, smoke density tests, thermogravimetric analysis (TG), scanning electron microscope (SEM) and fourier transform infrared spectroscopy (FTIR). The results show that synergistic flame retardancy and smoke suppression effect will be the best when TTF mass fraction is 3%, which exhibits flame spread rate of 4.3, equilibrium backside temperature of 84.8 ℃ at 900s, and smoke density rate of 14.2%. Char residue analysis indicates that adding TTF can promote coating to form more cross-linked structures and aromatic structures during burning, thus producing a more dense and thermally stable intumescent char layer against heat and mass transfer, which achieves better synergistic flame retardancy and smoke suppression effect.

Prediction of availability and remaining life of train control center based on Markov

QI Jinping, WANG Kang, ZHOU Yahui, LI Shaoxiong, ZHAO Ruihu, GUO Hao

2021, 31(10): 54-61. doi:10.16265/j.cnki.issn1003-3033.2021.10.008

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In order to prevent occurrence of equipment failure in the TCC, according to failure mechanism of TCC equipment, DFT was established, and reliability analysis was carried out by Markov theory, availability and remaining useful life prediction model of TCC based on Markov chain was proposed. State transition diagram was obtained from state transition relationship of each system, and then state equation was written out. Availability distribution functionand,reliability distribution functionand and formula of remaining service life were obtained. The research shows that weak link of TCC equipment was port input/output(PIO)>dian yuan(DY)> CI-TC>secure centre unit(SCU)>other communication interfaces. Considering CCF, steady-state availability of TCC reaches design standard, and average remaining life of TCC equipment is 186.256 months.

Experimental study on thermal characteristics of coal samples with different metamorphism degree during spontaneous combustion

JIA Tinggui, QIANG Qian, LOU Hezhuang, QU Guona

2021, 31(10): 62-67. doi:10.16265/j.cnki.issn1003-3033.2021.10.009

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To explore thermal characteristics of coal spontaneous combustion, different types and content of functional groups in coal samples were analyzed by FTIR. Then, parameters, such as weight loss and heat release, were analyzed based on multiple tests of TG-DSC, a kinetic equation was established and solved, and activation energy value E and pre-index factor A of samples were obtained. The results suggest that types of functional groups in coal molecules, in spite of their different metamorphism degrees, are similar. Content of hydroxyl group, aliphatic hydrocarbon and oxygen-containing functional groups in samples with low metamorphism is greater than that in those with high metamorphism, however, the latter's TG and DSC curves show deviation and hysteresis, its rate of coal oxygen recombination slows down, weight loss decreases and heat release increases. In the stage of weight gain, pre-index factor of coal with high metamorphism degree is the smallest, while in the stage of combustion, its activation energy and pre-index factor both increase, so more energy is needed for spontaneous combustion.

Study on lane-changing game behavior of vehicles in small spacing section between tunnel and interchange

SHANG Ting, WU Peng, TANG Boming, BAI Jingrong, ZHOU Liangyu

2021, 31(10): 68-75. doi:10.16265/j.cnki.issn1003-3033.2021.10.010

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In order to quantitatively study mandatory lane-changing behavior of vehicles in a small section between mountainous expressway tunnel and interchange exit, a game model was proposed in conformity with characteristics of mandatory lane-changing behaviors. Firstly, lane-changing process of off-ramp vehicles and characteristics of such a decision were analyzed. Secondly, considering influences of driving style on such behaviors, a game model was put forward between these vehicles and following ones on target lanes by using dynamic game theories of incomplete information, and a game payoff matrix was established in consideration of the time and security benefits of game players. Then, refining Bayesian Nash equilibrium under forced lane-changing strategy was calculated. Finally, the validity of lane-changing game model was verified through Netlogo simulation platform. The results show that the optimal lane-changing strategy is that off-ramp vehicles, in spite of different driving styles, should choose forced lane change, while those following ones on target lanes should slow down to give way to them. Drivers with different styles vary significantly in terms of distance between lane-changing completion point and interchange exit, and that distance for aggressive drivers is generally greater than that for cautious ones.

ETICS vertical temperature distribution and fire spread calculation

ZHOU Biao, WANG Kai, SUN Xukun, KE Wei, ZHANG Quan

2021, 31(10): 76-81. doi:10.16265/j.cnki.issn1003-3033.2021.10.011

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Overflow of window fire is one of the main reasons for ETICS fires. In this study, on the basis of discussing and analyzing influence of opening dimension and differential neutral axis on Yokoi calculation, distribution characteristics of vertical wall temperature under different flame power and opening size were explored. Then, through a series of tests, vertical spreading velocity of flame for different flame power and thickness of polystyrene foam board (EPS) were measured, and surface temperature and internal EPS burn area for different flame intensity and EPS density were attained. Finally, an ETICS fire risk index calculation method based on INDEX was developed. The results show that the calculated results of vertical wall temperature are in good agreement with experimental results, so are the results of flame spread. INDEX method can effectively clarify ETICS fire risk.

Analysis on flow field and shape structure of circular nozzle water jet

GAO Yabin, GUO Xiaoya, XIANG Xin, HAN Peizhuang, TANG Yibo

2021, 31(10): 82-88. doi:10.16265/j.cnki.issn1003-3033.2021.10.012

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In order to improve and optimize application of circular nozzle water jet technology in coal mines, based on theory of jet structure and velocity distribution of circular nozzle, flow field and morphological structure characteristics of the water jet were analyzed by using COMSOL numerical simulation software and high-speed camera technology. The results show that its structure can be divided into initial segment, transition segment, basic segment and dissipation segment, and the jet flow has diffusivity. Distribution of its axial velocity features piecewise function, and this velocity is a function of outlet pressure and distance from jet head to nozzle, while velocity distribution at jet section features self-mode, and that at each section can be regarded as a Gaussian distribution. At the beginning of cutting and erosion of coal and rock mass by water jet, there is about 400 ms of impact lag, main structure will be formed between 400 and 800 ms, and overall structure tends to be stable after 800 ms.

Experimental study on instability evolution mechanism of rib pillars during highwall mining

JIANG Juyu, YANG Huiwen, WANG Dong, WANG Laigui, HAN Xinping

2021, 31(10): 89-96. doi:10.16265/j.cnki.issn1003-3033.2021.10.013

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In order to study stability evolution mechanism of rib pillars during highwall mining, based on catastrophe theory, criteria for instability of coal pillars were derived. Secondly, similar material simulating experiment was conducted to study vertical stress's distribution pattern and evolution as well as their relationship with instability of coal pillars with different widths during coal mining and staged loading. Finally, test results were verified through numerical simulation. The results show that when the ratio of yield zone width to pillar width is greater than 88%, coal pillars will undergo instability failure. During mining process, distribution of vertical stress is in a saddle shape, which ensures a stable state. In the process of staged loading, coal pillars will see shear failure in turn from a small width to a large one, and vertical stress in the middle increases sharply, which is a precursor to a failure. The abrupt inflection point of vertical stress can be taken as a pre-warning criterion for coal pillar instability in engineering practice. It is also found that test results of stability are basically consistent numerical simulation ones, which verifies the rationality and reliability of the experiment results.

An improved FMEA method based on logical structure number

WU Yaonan, LIN Lei, REN Xinwen, WANG Longting, LIU Zhihui, LIU Zengkai

2021, 31(10): 97-104. doi:10.16265/j.cnki.issn1003-3033.2021.10.014

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In order to solve problems of subjective error, structure conversion and logic confusion in traditional FMEA, an improved FMEA analysis method based on logical structure number was proposed. Fuzzy sets and AHP were used to reduce subjective errors, generates logical structure numbers through FTA analysis, logical structure numbers was used to realize conversion of failure causes to failure modes, and data was processed through TOPSIS to obtain risk priority number of each failure mode to make FMEA analysis have logical and integral. Method was applied to research of FPSO three-phase separator to verify effectiveness of method. The results show that main failure mode of three-phase separator found by this method is more accurate, more suitable for production practice, and more conducive to operation of engineering personnel.

Coal fracture's compressibility and permeability under proppant embedding

CHENG Qiaoyun, LI Bobo, LI Jianhua, GAO Zheng, WANG Bin

2021, 31(10): 105-111. doi:10.16265/j.cnki.issn1003-3033.2021.10.015

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In order to explore coal fracture's compressibility and permeability under influence of stress and proppant, embedding depth of proppant was quantified by using Hertz contact theory, and a calculation formula of fracture compressibility was derived. Meanwhile, a permeability model was established considering coupling influence of multiple factors, and its validity was verified. The results show that embedding depth of proppant is proportionate to effective stress, and permeability decreases first and then levels off as effective stress grows. When gas pressure is constant, embedding of proppant reduces compressibility of coal fissures, but while at a constant embedding depth, the compressibility increases along with that of gas pressure. Meanwhile, permeability of coal fractures with proppant is much higher than that in the original state, but more paving layers lead to less obvious anti-reflection effect. As the established model's calculated value of permeability is generally consistent with test results, it can can effectively characterize seepage features of coal under actions of stress and proppant.

Key personnel risk assessment method based on improved AHP

WU Renbiao, HE Yuxiang, JIA Yunfei

2021, 31(10): 112-118. doi:10.16265/j.cnki.issn1003-3033.2021.10.016

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In order to address the lack of scientific quantitative evaluation on passenger security screening classification of civil aviation in the future, an evaluation system was established by using AHP to realize passenger background analysis and risk warning. Considering the shortcoming of traditional AHP method, namely its high subjectivity as evaluation indicators were selected through artificial experience, an improved AHP was proposed. A sample database describing personal characteristics was created through JJATT, and RF was applied to screen characteristics of the database before a personnel risk evaluation system was developed with optimal combination of characteristics as evaluation indicators. Then, index weights were determined through AHP method, and a risk assessment method for key personnel was put forward based on evaluation index scoring table. Finally, the method was applied to evaluate risk levels of personnel in large sample cases and real cases. The results show that the evaluation accuracy rate of proposed method for multiple sample sizes is above 92%, and it can evaluate personnel risk level of samples. And improved AHP, as the core of the proposed method, is verified to have certain rationality.

Decision-making modeling of metro emergency evacuation behavior considering psychological heterogeneity

WANG Lixiao, YU Jiangbo, SUN Xiaohui

2021, 31(10): 119-126. doi:10.16265/j.cnki.issn1003-3033.2021.10.017

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In order to explore psychological heterogeneity of evacuees and their route choice behavior mechanism, a LCM was established. Firstly, psychological latent variables were used to classify people through latent profile analysis(LPA), and optimal number of psychological latent classes was determined. Then, reliability of the classification was verified through analysis of variance. Finally, route choice preferences of people in different psychological latent classes were analyzed, and their choosing results predicted by LCM were compared with actual choices. The results demonstrate that evacuees can be divided into 5 psychological latent classes, among which the third class only tends to choose the shortest route, and preference of the fifth for the shortest one is similar to that for non-crowded route, and their strategy in choosing routes is more flexible. Compared with general models, LCM features higher accuracy in predicting choice results, and its probability is closer to reality.

Safety evaluation of gas pipelines with defects under surface load

LIU Xiaoben, WANG Baodong, ZHANG Dong, ZHANG Hong

2021, 31(10): 127-135. doi:10.16265/j.cnki.issn1003-3033.2021.10.018

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In order to study mechanical properties and failure behavior of gas pipelines with defects under surface load, a safety evaluation method for them was proposed. Firstly, a pipe-soil interaction model for gas pipelines with volume defects under surface load was established by utilizing general nonlinear finite element software ANSYS. Then, their failure mechanism under the load was revealed, and impacts of parameters, such as internal pressure, defect location, defect depth and length, on failure process were analyzed. The results show that these gas pipelines with defects fail under surface load since Mises stress at defect position and arching line position at both sides exceeds yield limit. Factors like internal pressure, defect location, defect depth will directly affect critical failure load of pipelines, and they are prone to fail at 0° position. Moreover, their safety evaluation curve can be obtained by calculating critical failure load under combined working conditions.

Stability and safety analysis on traffic flow mixed with ICV

YAO Zhihong, JIN Yuting, WANG Sichen, HU Lu, JIANG Yangsheng

2021, 31(10): 136-143. doi:10.16265/j.cnki.issn1003-3033.2021.10.019

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In order to reveal influence mechanism of ICV on traffic flow, firstly, considering degradation mechanism of ICV, its following mode and proportion in mixed traffic flow were analyzed. Then, different following modes were described by utilizing intelligent driver model (IDM) with different parameters, based on which criteria to determine stability of mixed traffic flow were derived. Finally, standard deviation coefficient of car speed, time-to-collision(TTC), exposed time-to-collision(TET) and integrated time-to-collision (TIT) were selected as safety evaluation indexes of the traffic flow, and numerical simulation experiments were conducted based on cellular automata. The results show that as penetration rate of ICV increases, dispersion degree of vehicle speed gradually decreases, so does the risk of rear collision. Therefore, application of ICV can significantly improve stability and safety of traffic flow.

Emergency evacuation decision optimization for commercial pedestrian streets based on ant colony algorithm

JIANG Xue, YANG Huan, ZHANG Peihong

2021, 31(10): 144-151. doi:10.16265/j.cnki.issn1003-3033.2021.10.020

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In order to analyze safety of large-scale crowd emergency evacuation under guidance of emergency evacuation plan based on decision optimization in commercial pedestrian street. Taking a commercial pedestrian street as an example, the improved adaptive ant colony algorithm was used to optimize the evacuation decision-making and the optimal design of evacuation plan. Combined with Pathfinder software, the personnel evacuation behavior based on optimized evacuation plan was simulated numerically, and the efficiency and safety of large-scale crowd evacuation in commercial pedestrian streets before and after decision optimization were compared and analyzed. The results show that the evacuation efficiency of large-scale crowd induced based on the optimized evacuation plan can be improved by 8.86% in a fire-free environment. The evacuation efficiency in the fire environment increased by 6.57%. The decision-making optimization of large-scale emergency evacuation effectively alleviates the situation of personnel cluster retention at some safety exits,the integral decision-making optimization of emergency evacuation is realized.

Study on space network of potential secondary accidents of natural disasters

WANG Wei, QI Qingjie, LIU Wengang

2021, 31(10): 152-158. doi:10.16265/j.cnki.issn1003-3033.2021.10.021

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In order to study relationship between potential secondary accidents of natural disasters and disaster bearing bodies' defense, concept of spatial network of secondary accidents was proposed. Firstly, definition of the network was given based on theory of factor space considering factors of potential accidents, and evolution process of these accidents were described by using relationship between disaster bearing body, disaster bearing body index, hidden danger and accidents. Then, the spatial network was established, and hidden danger model library and accident model library were provided. Finally, analysis method of potential secondary accidents were proposed, secondary hidden danger, accident, hidden danger mode and accident mode of coal mines were obtained, and tracing mechanism was established. The results show that rectification object of eliminating hidden danger and preventing secondary accidents is accurate to disaster bearing body index, which provides a new method for study of secondary accidents caused by natural disasters.

Analysis of AE parameters of waveguide rod at different loading rates under three-point bending

WU Xin, WANG Xuemei, LUO Xiaoyu, ZHU Xu, LIN Huali

2021, 31(10): 159-166. doi:10.16265/j.cnki.issn1003-3033.2021.10.022

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In order to explore change characteristics of AE signal related parameters during sliding process inside slopes, and to predict their sliding rates, three-point bending tests of sand-filled active waveguide rods were carried out under different loading rates. Then, relationship between AE parameters, such as amplitude, b-value, ringing count, energy and main frequency amplitude, and loading rate was analyzed. The results show that amplitude of AE signals increases gradually while b value decreases along with the increase of loading rate. Ringing count increases linearly with the rise of loading time, and its growth rate increases in a power function as loading rate increases, while energy increases in an exponential function with that of loading time. Moreover, main frequency amplitude increases with that of loading time and loading rate, and its changes are more significant in low frequency and middle and low frequency bands (20-200 kHz).

Numerical study on infrared deicing process in climatic wind tunnels

ZHOU Fan, WU Jinmo, LU Pengfei, LIN Hongxia

2021, 31(10): 167-173. doi:10.16265/j.cnki.issn1003-3033.2021.10.023

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In order to solve residence ground freezing problem in climatic wind tunnels, an infrared deicing method was proposed by utilizing inner radiation simulation system. A calculation model of radiation distribution and a mathematical model of three-dimensional unsteady phase-change process were established to study melting process of ground ice layer in climatic wind tunnels. The results show that the complete melting time of ground ice under infrared deicing conditions is 2-6 hours. The ice layer melts from top to bottom, from edges to the center, and an inverted trapezoidal ice shape can be obtained in melting process, which enables addition of mechanical deicing during infrared deicing to improve deicing efficiency. Moreover, the melting time of ice layer will reduce by 1.2 hours for each increase of thickness by 10 mm. The greater thickness leads to more significant inverted trapezoid ice shape.

Simulation modeling on emergency response process for LNG-fueled vessel via GSPN-MC method

HU Shenping, LI Shengyuan, ZHAO Rui, LI Shuaizhao, WANG Xinya

2021, 31(10): 174-181. doi:10.16265/j.cnki.issn1003-3033.2021.10.024

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In order to eliminate risks of fuel leakage in LNG-fueled vessels, a GSPN isomorphism with its MC method was proposed to simulate response process for such leakage emergencies. Firstly, leakage risks of LNG-fueled vessels were described, and emergency response process flow was developed. Secondly, GSPN model of emergency response system process and its isomorphic MC were established. Finally, simulation analysis was carried out with LNG leakage response exercise as an example, and major performance parameters, like steady state probability of the system, were obtained. The results show that problems of information accumulations tend to appear in the stages of preliminary preparation and judgment on leakage degree of LNG storage tanks. Situation judgement and summary of subsequent disposal measures take a relatively long time, and thus should be the focus of process optimization.

Structural similarity construction method of "scenario-response" model for emergency drills

LU Jintao

2021, 31(10): 182-188. doi:10.16265/j.cnki.issn1003-3033.2021.10.025

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In order to better apply "scenario-response" model to the field of emergency management, emergency drill scenarios were established by using structural similarity method. Firstly, a hierarchical scenario model was constructed, i.e. "event-environment-scenario state-task-emergency action-resource subject" module. Secondly, calculation methods of each module's scenario similarity and its evaluation matrix were proposed. Finally, structural similarity analysis method was adopted to verify application of the model in oil and gas explosion accident,oil spill accidents. The results show that the structural similarity method is used to design and calculate the similarity between the currently available emergency exercise plans and the proposed emergency plan to obtain the proposed emergency plan in the current situation.

Impact situation assessment of multiple connection number on miners' physical and mental safety

NIE Xingxin, MA Yijie, AI Weixi, SUN Hao

2021, 31(10): 189-195. doi:10.16265/j.cnki.issn1003-3033.2021.10.026

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In order to effectively analyze impacts on physical and mental safety situation of miners in deep wells, an influence index system of their safety was established. Then, FAHP method and IE method were employed to obtain final weights, and an impact assessment model of multiple connection number based on set pair analysis was developed to identify situations of miners' safety being influenced and its development trend. Finally, the model was applied to a case study in a hot wet gold mine in Henan province, physiological, psychological and behavioral indexes of its miners under three wind speed conditions and five temperature ranges were measured, and five element connection number was used for impact assessment. The results show that the development trend of miners' own safety in high temperature mines is constantly changing, featuring fluctuating forward variance and a mixture of similarity and difference. Indicators of reverse trend or equalizing trend include arm strength, reflexes, core temperature and heart rate, which could lead to an increase of risk degree.

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