To effectively implement safety production investment in bridge construction projects，GRA was used to analyze the correlation between the influencing factors of construction safety behavior from both the project supervision organization and construction units，and then the core causal factors were determined. Subsequently，a SD model was proposed to investigate the interaction mechanisms among the core causal factors. Finally，the vulnerability and resilience of the core causal factors affecting construction safety behavior were analyzed. The results indicated that extreme fines imposed by construction units，high supervision costs for project monitoring organizations，and low initial proportions between parties were the key vulnerability factors of the safety behavior in bridge construction. Reasonable economic fines，appropriate supervision costs，and enhanced training to improve frontline personnel's safety awareness significantly improved the construction safety behavior resilience.

In the new security pattern，the power grid safety management was promoted to transform from the traditional mode to the digital，information，and intelligent mode during the life-cycle of safety production. Based on patent data of China's power grid intelligent security from 2008 to 2023，the patent map was performed using network centrality analysis and main path analysis. Then，key patent technology subgroups were obtained to systematically analyze technological development and key points of power grid intelligent safety. Based on patent maps and expert opinions，the entropy weight-TOPSIS method was used to evaluate the support of China's existing intelligent safety technology community for power grid security and intelligence. The results showed there were 11 key technology communities for the power grid intelligent safety technology，and power grid intelligent safety process technology was the most excellent knowledge group. Among the 11 types of power grid intelligent safety technology communities，technologies including intelligent control，intelligent dispatching，and network communication safety were with higher support for power grid intelligent safety. Intelligent security technology can well support the safety control and stability capabilities in the traditional safety goals of the power grid. Furthermore，it supports the safety governance and active security capabilities in the modern safety goal of the power grid. However，the support for security resilience capabilities was insufficient.

Aiming at the problem that the regional environment of cultural relic buildings in a forest environment is complex，and it is difficult to accurately evaluate the regional firefighting and rescue ability，an evaluation method of firefighting and rescue ability of a single cultural relic building coupled with forest factors was constructed based on Analytic Hierarchy Process (AHP)，which covered 19 secondary indicators such as building materials，forest fire separation zones，and fire water sources. Based on single-unit assessment，a firefighting and rescue capacity assessment model based on the variable-rights method was established from the regional perspective for the centralized area of cultural relics buildings in the forest environment. A mixed-type variable-rights function dominated by penalties was introduced. The model was established by setting up the evaluation strategy，determining the penalties and incentives intervals，differentiating the protection level of cultural relics buildings，and putting forward the risk level division method. The firefighting and rescue capacity of the forest environment heritage building concentration area (Yuelu mountain scenic spot) was evaluated by combining the fixed-rights method and variable-rights method through field research and data collection. The results show that the number of individual heritage buildings rated as 'excellent，good，moderate，substandard，poor' accounted for '12%，20%，32%，20% and 16%'. For the centralized area，the fixed-rights method scored 75.27 (Level III，no need to take upgrading measures)，while the variable-rights method scored 69.97 (Level IV，need to take upgrading measures). Therefore，it is recommended that measures such as installing additional electrical fire warning systems and increasing forest fire breaks be taken to enhance firefighting and rescue capabilities.

Coastal chemical industrial parks have frequently experienced lightning strikes，which seriously threaten production safety. A risk assessment method based on HCL methodology was proposed to assess Natech (Natural-technological) accidents triggered by lightning strikes on storage tanks in these parks. Firstly，ESD and Fault Tree Analysis(FTA) were employed to qualitatively analyze the evolution paths of Natech accidents caused by lightning strikes on storage tanks，providing a visual foundation for blocking the accident transmission process. Secondly，BN were used to quantitatively calculate human error probabilities and assess the hybrid causal relationships of lightning-induced storage tank accidents. Finally，HCl methodology was applied to visually deconstruct the complexity and uncertainty of Natech accidents caused by lightning strikes on storage tanks. The research results indicate that decision-making error is the primary risk source in the human error model. Organizational atmosphere，psychological state，poor working environment and inadequate supervision are identified as the main factors leading to frequent human errors. The lack of effectiveness of lightning protection facilities is recognized as the trigger in the accident chain of lightning strikes on storage tanks. To reduce the severity of risk scenarios，emphasis needs to be placed on strengthening the control of full-surface fires and pool fires.

To improve urban response capabilities in dealing with dynamic disasters，a MCMPOP was proposed for planning emergency vehicle paths in dynamic disaster environments. This model considered path safety as a multiplicative weight and vehicle path length and travel time as additive weights. Then，MCMPOP was addressed by improving the RSA. To verify the effectiveness of the improved RSA in solving the MCMPOP，510 simulation experiments were conducted comparing the computer time and solution quality of the Non-dominated Sorting Genetic Algorithm(NSGA)-Ⅱ and the improved RSA. Furthermore，"7·20" Zhengzhou rainstorm event was selected as a case study to validate the model. The results show that，compared to the NSGA-II，the improved RSA can find a complete set of Pareto optimal paths，effectively ensuring the optimality and computational efficiency of the algorithm. By using RSA to solve MCMPOP，it is possible to successfully select Pareto optimal paths with the shortest travel path lengths and the lowest time costs within the acceptable path safety range for emergency vehicles，providing more reliable routes for emergency vehicles and enhancing the urban emergency management capabilities.

The aim of this study is to investigate the dispersion of aluminium powders with different SF in a 20 L spherical container. By establishing a numerical model describing the formation of a two-phase dispersion system of dust carried by a gas stream，including the equations of the gas flow and the trajectory of the dust particles，unsteady numerical simulations were carried out. The spatial distribution of dust，the turbulent kinetic energy and velocity at the center of the spherical chamber with time changes were analyzed under the conditions of SF of 0.2，0.4，0.6，0.8 and 1.0，respectively. The results show that the dispersion of airflow-carried dust inside the ball chamber can be divided into four stages，including powder intake，diffusion，stabilization and settling，and the dispersion uniformity and maximum velocity values are enhanced with the increase of SF. The bigger SF is，the closer the particle shape is to spherical，and the better the dispersion of aluminum dust is. The smaller SF is，the easier the dust will accumulate near the wall surface. When the nominal concentration is certain，SF ≤ 0.4，the peak concentration increases with the increase of SF，SF > 0.4，the peak concentration decreases with the increase of SF. The maximum value of the turbulent kinetic energy of the aluminum powder-air mixture decreases with increasing values of SF，the peak velocity of the aluminum powder particles increases with increasing values of SF.

In order to explore the influence of road section characteristics on path redundancy and the redundancy ability of road traffic networks under emergencies，based on the traditional method of path redundancy quantity in road networks，considering the efficiency difference and overlap degree between effective paths，a redundancy evaluation model based on path diversity and redundancy ability under emergencies was constructed. The influence of different costs on path diversity and the influence of emergencies on redundancy ability were analyzed，and the sensitivity analysis of redundancy ability was carried out. The results show that the path diversity in the road traffic network depends on the type of travel path cost and the difference between the travel cost of the road section. The closer the travel cost of the road section is，the higher the number of effective paths is，and the higher the path diversity is. In the emergency scenario，the redundancy of the road network depends on the importance of the failed road section. The more important the failed road section is，the lower the network redundancy is. The increase of travel cost tolerance within a certain range helps to improve the redundancy capacity of the road network during emergencies. Too high or too low travel cost tolerance will not significantly improve the redundancy capacity of the network.

In order to prevent and control the explosion hazards of ethylene/polyethylene hybrid mixture，bicarbonate was selected as the explosion suppression powder，and the explosion suppression experiment was carried out in a 20 L spherical explosion device to explore the explosion inhibition effect and mechanism of different bicarbonate on ethylene/polyethylene hybrid mixture. The differences of explosion inhibition performance of different bicarbonate on the hybrid mixture were discussed. The results show that the hybrid mixture is more difficult to inhibit than the single-phase polyethylene. With the increase of ethylene concentration，the explosion inhibition of the hybrid mixture becomes more difficult. The bicarbonate has an inhibitory effect on the ethylene/polyethylene hybrid mixture with different concentrations，and the inhibition efficiency is affected by the concentration of ethylene and bicarbonate. Bicarbonate can inhibit the ethylene/polyethylene hybrid explosion through physicochemical reaction during the polyethylene explosion. The decomposition and endothermic properties of potassium bicarbonate and its retardation effect on polyethylene pyrolysis are better than those of sodium bicarbonate，so the inhibition effect of potassium bicarbonate on the explosion of ethylene/polyethylene hybrid mixture is better than that of sodium bicarbonate.

To effectively evaluate the safety risk status and optimize safety management strategies in university laboratories，a dynamic safety assessment method was proposed based on a multi-layered safety control structure model. Firstly，a multi-layer safety control structure model was developed to identify the causal factors and control deficiencies of fire and explosion accidents in the university laboratory. Then，a safety dynamic feedback evaluation method was developed integrating an accident model based on system theory and Bayesian networks. Finally，the proposed evaluation model was used to determine the risk probability，analyze risk factors affecting safety incidents，and identify key risk factors in university laboratory safety. The results indicated that the proposed evaluation method based on the safety control structure model covered all risks identified by traditional methods and identified potential risks. Furthermore，the incorrect operation of hazardous chemicals，violation of operation procedures during the experiment，and the aging，short circuits，or defects in electrical lines were key risk factors affecting laboratory safety risks of universities.

In order to guarantee the structural safety of masonry structures in existing buildings and prolong their lifespan，a SHM system and the mean value control charts were employed to investigate the condition evaluation and early alarming mechanism of these structures. The monitoring items for this structure were chosen to be the load-bearing wall cracks and the relative displacement of window sills. The data about structural reaction and ambient temperature was collected，and a correlation model between these two factors was built. Additionally，the correlation model was employed to replicate the temperature impact of the data collected from monitoring the structural response. Ultimately，the structural condition index was suggested and integrated with the mean value control chart to assess the early detection of potential issues in the structure. The structural condition index represented the disparity between the simulated outcomes of the correlation model and the real measured values. The findings demonstrate that the system has the capability to gather real-time monitoring data，accurately assess structural health，and promptly alert about structural damage. The monitoring data indicate that the crack width varies between 0.746 and 4.391 mm，while the sill relative displacement spans from 1.282 to 5.690 mm. Both of these variations are within the acceptable safety limit. From the findings of the mean value control chart in the early alarming system，the fracture width and relative displacement of the window sill are within normal parameters.