Showing papers in "Journal of Safety Science and Technology in 2015"

Statistical analysis and countermeasures on larger and above grades accidents of dangerous chemical enterprises from 2001 to 2013

Abstract: Based on the accidents database in the governmental website of the State Administration of Work Safety,the accidents of dangerous chemicals enterprises from 2001 to 2013 with larger and above grades level in the consequences severity were analyzed and studied systematically and comprehensively. From the aspects of the developing tendency of accidents,casualties,accidents types,month,time periods and regions of occurrence etc.,a deep and systematic analysis was made by using mathematical statistics method to reveal the inherent characteristics and laws of typical accidents in the dangerous chemical enterprises. Finally,some countermeasures and suggestions on preventing and control of the accidents in the dangerous chemicals enterprises were provided from the following aspects: improving the process inherent safety,completing the safety supervising system,strengthening the accident emergency treatment and perfecting reporting and statistics system of accidents.

Prediction model for outburst of coal and gas based on QGA-LSSVM

Abstract: To predict the outburst type of coal and gas quickly and effectively,the main influence factors were analyzed and extracted by gray correlation and factor analysis modelThe quantum genetic algorithm(QGA) was applied to optimize the parameters of the least squares support vector machine(LSSVM)Finally,the prediction model for outburst of coal and gas based on QGA-LSSVM was establishedBy selecting the historical measured data sets in Yanshitai mining area,the model was trained and tested by the proportion of 96: 20,and the prediction results were compared with the results of other prediction modelsThe results showed that it can effectively remove the factors which have a little impact on the outburst of coal and gas by gray correlation analysis,and it can reduce data redundancy by using factor analysis to extract the common factorsThe LSSVM model after optimization by QGA can avoid the results to fall into the local optimal solution,and it can effectively predict the outburst type of coal and gas with an error rate of zero

Emergency scenario evolution and extraction method of key elements

Abstract: According to the characteristics of difficult in emergency disposal,the emergency management mode must be converted to " scenario-response". The system model of emergency scenario was established based on understanding the evolution mechanism of emergency scenario from three main principles,namely,the system complexity,future-open thinking and sequential property. On this basis,the extraction method of key elements in emergency scenario network was designed. Taking the main contents of three aspects,including hazard source formulation,emergency evolution and emergency response,as the main body of scenario network,and taking the involved influence factors of the above three aspects as branch,the key elements of scenario network were extracted appropriately and divided into four categories. The method compensates the blank in the theory about extraction method of key elements in scenario network,and provides theoretical support for the emergency scenario construction.

Investigation and analysis on personnel density in commercial complex

Abstract: The personnel density which is the foundation of evacuation design on buildings has a certain feature in commercial complex.With the black box theory and the correlative knowledge of statistics,the calculation model of personnel density in commercial complex was built.Combined with the survey data for two classical commercial complexes,the personnel densities,the laws of personnel density distribution at different times of the day,and the ratio of average personnel density on working day,rest day and holiday were obtained.The corresponding measures of fire prevention management were put forward.The results showed that the personnel density in commercial complex is less than the recommended value of the present standard,so it can provide reference to safety evacuation design of commercial complex.

Investigation and analysis on imitation and learning of unsafe behaviors for construction workers

Abstract: In order to control the spreading and prevalence of unsafe behaviors among construction workers,the modes,processes and influence factors of imitation and learning of unsafe behaviors for construction workers were discussed by behaviors investigation,theoretical analysis and case study,based on the social learning theory. The results showed that: a) The imitation and learning are the main methods and ways for replicating and spreading of unsafe behaviors. It can lead to or catalyze some new unsafe behaviors. b) The modes of imitation and learning of unsafe behaviors for construction workers include audiovisual,imagining and participating,and the audiovisual is the most important one. c) The influence factors of imitation and learning of unsafe behaviors for construction workers are from the examples and their behaviors,imitators and processes of imitation and learning,among which the authority and influence of examples are the most important reinforcing factors,and the deterrent of consequence by unsafe behaviors is the most important inhibited factor.

Study on metro evacuation simulation based on crowd characteristics during different time period

Abstract: In order to understand the influence of crowd characteristics on evacuation during different running time periods,the number of passengers entering the metro per hour was counted The running time periods of metro were divided into three time periods,including peak time period,flat peak period and low peak period Besides,the number of trains pulling in station during each time period was recorded The crowd characteristics which contain age,luggage carrying condition and velocity of passengers during different running time periods were recorded On this basis,the evacuation simulation modeling of metro station was done by utilizing the Pathfinder software The simulation results of personnel evacuation during different running time periods were analyzed from the aspects of evacuation time,congestion points,evacuation route and utilization rate of exits It showed that when two trains pulled in station during peak time period,the phenomenon of evacuation congestion was obvious,and the personnel evacuation had some differences between two trains and single train pulling in station When two trains pulled in station during flat peak period and low peak period,the evacuation congestion points were obvious,and the utilization rates of exits were basically consistent At last,some suggestions to improve efficiency of metro evacuation were put forward,such as emphasizing the metro evacuation management during different running time periods,enhancing the evacuation guidance in congestion points,and shortening the running interval of trains

Study on simulation model of public place evacuation in a familiar environment

Abstract: The simulation model which can describe the actual evacuation behavior of personnel familiar with the environment in public places accurately was built to guide the development of software with a high degree of simulation reliability.The major factors influencing the evacuation behavior of personnel familiar with the environment were analysed and quantified on the basis of referencing Helbing social force model,at the same time,the concept of being climbed degree was introduced to distinguish the influences of different obstacles in the evacuation,and then the model was established combining with the principles of molecular simulation.Finally,the simulation of a representative virtual scene was implemented by using C # programming language.The simulation results showed that the model can fully reflect the evacuation path and move speed change of personnel familiar with the environment,and it is suitable for high-speed rail passenger stations and other public places.

Safety analysis of coal mine disaster based on factor analysis

Abstract: In order to understand the relationship between safety and disaster factors in coal mine,taking a large number of existing safety record information as the basis data,the safety of coal mine disasters was analyzed with factor analysis method in the theory of factor space. The basic features of factor space and factor analysis method were discussed,as well as the issues of current qualitative safety assessment. Through practical case analysis,it showed that: factor analysis method can dig out the causality relation between disaster factors in safety information and coal mine safety,and can analyze the reliability of obtained results. The order of safety factors of the case was caving gas rock burst permeable. The basic information was more objective,and the reliability of analysis results was 85. 7%.

Study on evaluation of emergency plans

Abstract: To effectively evaluate the emergency plans is the key link to improve the effectiveness of emergency plans and ensure to play the desired effect of emergency plans. At present,the evaluation on emergency plans in China is mostly template evaluation,and the basis and the content of evaluation remain to be improved. The application of contrast method in evaluation of emergency plans was discussed. Taking improving the emergency preparedness ability as purpose,the emphasis of evaluation was put on five aspects of emergency plans,including the adequacy,feasibility,completeness,acceptability and compliance,and the revision suggestions of emergency plan were put forward. The evaluation process was described in detail by taking a real emergency plan as example.

Numerical simulation of fire smoke flow in typical structure of building corridor

Abstract: Four kinds of building corridors with typical structure including the bar type,L type,T type and circular type were selected as the research objects,and the fire simulation software FDS was applied to analyze the smoke transportation laws in fire scenarios of the four types of corridors with typical structure The influence of building structure on transportation and temperature distribution of fire smoke was obtained preliminarily For L type and circular type corridors with closed corner,the hot smoke is easily to accumulate in the corner of corridor by the effect of blocking by closed structure and anti buoyancy While for no matter what kinds of corridors,the hot smoke is easily to accumulate in the end of corridor by the effect of wall restriction and anti buoyancy The intersection of T type corridor has a better circulation and is relatively safe The temperature in the corner and end of corridor which are easy to cause smoke accumulation will also rise,while at present,the evacuation stairs of many connecting corridors have been set on both ends of the corridor,which is unfavourable for evacuation So more importance should be attached in these places,and the fire prevention and smoke exhaust measures should be enhanced

Experimental study on anchorage performance by reaming in bottom of bolt hole for soft coal seam

Abstract: In terms of the low anchorage performance of bolt in the roadway of soft coal seam has become the bottleneck which restricts the development of bolt support technology,a method to improve the anchorage performance of bolt by means of inverted wedge reaming in bottom of bolt hole was put forward. A bottom reaming device with a single wing was developed,and both laboratory and practical underground experiments were carried out. The results showed that the designed bottom reaming device with a single wing is scientific and feasible. The anchorage performance of bolt with inverted wedge reaming in bottom of bolt hole increases more than one times,which establishes the foundation for application of bolt support in roadway of soft coal seam.

Analysis on pressure loss of drilling cuttings movement caused by gas-solid coupling in gas extraction borehole

Abstract: Based on gas-solid two-phase fluid dynamics theory,the drilling cuttings movement pressure loss caused by gas-solid flow in borehole,the partial pressure loss generated by air flow through the joint diameter reducing position,borehole shrinkage position and drilling cave area of the gas extraction borehole were analyzed. Combining with engineering case,the air pressure loss of drilling system was calculated and analyzed. The results showed that the friction pressure loss of gas-solid flow is the main components of air pressure loss in drilling system. Openedtype drilling cave has fewer impacts on air pressure loss of drilling system,but filled-type drilling cave can form great pressure loss. According to the geological conditions of coal seam and drilling design parameters,the method was applied to calculate the air pressure loss of drilling system. It can provide the scientific basis for optimizing the compressed air system.

Three-dimensional numerical analysis on landslide control of composite slope with multiple weak layers

Abstract: The slope control project on landslide area of Baiyinhua No 2 mine is conducted aiming at the composite slope consisted of south non- working slope and south dump with poor stability The landslide body is controlled by multi- layer weak layers,and the slope instability is easily to happen in control process,so the partition strip mining scheme is adopted,and the three- dimensional effect of slope control is made full use in instability failure study and stability analysis of slope Choosing the typical section of landslide area as the research object,based on the strength reduction method( SRM),using finite difference software FLAC3 D,under the conditions of two kinds of excavation,the numerical simulation analysis was carried out concerning stability rules and failure mechanism of composite slope with multiple weak layers,and the influence of multiple weak layers on instability failure and stability of composite slope was revealed The results showed that the weak layer was excavated to a certain width in control process,and sliding body dislocated horizontally along the coal floor of weak layers and destroyed vertically under tensile strength With the growing exposed width of weak layer,the slope stability decreased obviously,which indicated a three- dimensional effect in slope control When excavating to 3- 3 seam floor,the excavation slope angle was 20 °,and the exposed width of weak layer was 400 m,the stability factor of slope reached the safety reserve factor 1 1 exactly It was suggested that the mine party should adopt this scheme firstly,in order to recover the maximum coal resources

Design on emergency exercise of work safety accidents

Abstract: Aiming at the problems of without unified standard in planning and lack of operative specifications in implementation for emergency exercise,based on comprehensive survey of the related achievements on exercise design at home and abroad,an emergency exercise preparation pattern which put emphasis on emergency scenario construction,'persons in charge,resources,measures,accident response' matching and the other factors was put forward proceeding from the actual situation of emergency disposal. Meanwhile,the implementing method on emergency exercise of work safety accidents which takes the table- top exercise,simulation test and process evaluation as core was established by means of simulated disposal case of xylene leakage in a petrochemical enterprise. The ideas,methods and steps for emergency exercise of work safety accidents were clarified,and it has important reference values for enterprises to carry out emergency exercise and effectively handle work safety accidents.

Safety analysis of waste heat boiler based on FMECA and fuzzy FTA

Abstract: In order to ensure the safe operation of waste heat boiler and prevent explosion accident,the FMECA and fuzzy FTA methods were applied to study the accident causes of waste heat boiler. Through analysis and identification on potential risk factors of waste heat boiler,the types,reasons and corresponding solutions of equipment faults were explored. The fuzzy FTA was introduced to qualitatively and quantitatively analyze the explosion accidents of waste heat boiler,the framework of safety analysis on waste heat boiler based on FMECA and fuzzy FTA was constructed,and the fuzzy probability of the accident and the sensitivity analysis on the basic events were also acquired. It showed that the reliability of waste heat boiler is approximately 96. 92%,and the events including drain contamination without according to stipulations,malfunction of alarm,pressure connection tube plugging of safety valve and unqualified deaerator have the biggest impact on the occurrence probability of top event. It provides support for the safety decision of this system.

Study on emergency evacuation behaviors of passengers in a subway station( 2)——Behavior analysis

Abstract: In order to master the evacuation behavior response of passengers in case of emergency,based on an accident case about emergency evacuation of passengers in tunnel of a subway station,through the observation analysis,the evacuation behavior characteristics,evacuation route rules,panic mood distribution and rules in train compartment were studied. It showed that the evacuation behaviors of passengers present the characteristic of wave rule to diffuse and transfer. When the passengers are panic to flee,the phenomenon of crowd gathering with the same age and sex appears,the herd behavior also appears,and the route presents the arc phenomenon. The panic mood of passengers decreases with the increase of distance to the accident site,which shows a negative correlation. It can provide numerical reference for metro design personnel,subway safety evaluation,simulation model,and emergency evacuation plan,and propose the optimization suggestions to the existing safety evaluation problems in tunnel of subway station.

Experimental study on influence of particle size to combustion and explosion characteristics of sulfur

Abstract: The parameters tests on combustion and explosion characteristics of sulfur dust in wet forming process were conducted.Eight groups of sulfur dust with the mesh number of 16 to 35 mesh, 35 to 60 mesh, 60 to 80 mesh, 80 to 100 mesh, 100 to 120 mesh, 120 to 160 mesh, 160 to 200 mesh, and 200 mesh were selected, then four parameters including ignition temperature of dust layer, minimum ignition temperature of dust cloud, minimum ignition energy of dust cloud and lower explosion limit were measured, and the combustion and explosion character-istics of sulfur dust with different particle size groups were determined.It provides the basis for the making of moni-toring standard on sulfur dust concentration in sulfur wet forming system.

Discussion on concept and evaluation index of gas well integrity

Abstract: So far,neither the clear conception of gas well integrity nor the integrity evaluation index system of producing gas well have been stipulated in international community. The concept of gas well integrity was initially proposed by analyzing the shortcomings in existing interpretation of gas well integrity. It was emphasized that gas well integrity is a state in which the risk of uncontrolled flow for formation fluid is within acceptable range. The evaluation index system of gas well integrity was established from the aspects of integrity management,barrier equipment and monitoring state according to the complemented definition,and the relationship between each evaluation index and gas well integrity was analyzed. The barrier equipment integrity is the core of gas well integrity,the integrity management is the key to improve gas well integrity,and monitoring state is the most direct judgment basis of gas well integrity. It provides a reference for related research and dynamic risk assessment of gas well integrity.

Setup mode and institutional structure of daily emergency management agency in our government

Abstract: Daily emergency management agency is in charge of daily affairs about emergency management of government,and is responsible for the specific coordination of governmental emergency response action. Currently,the Emergency Management Offices of governments in China should be reformed because their power is too small,their level is too low,their ability is limited,they have functions conflict with other institutions,and a simple upgrade of them will lead to new problems. In the representative setup modes of daily emergency management agency,FEMA of the United States can be adopted as a reference. The governments of China should setup a comprehensive emergency management department to integrate some emergency agencies which just carry out single function,perform power of coordination with the other departments in emergency management field,and undertake the responsibility as emergency management office of the governments at the same time.

Study on synergy measurement of safety emergency management on dam group in hydropower station

Abstract: Aiming at the situation of resources waste caused by lacking of initiative synergy in safety emergency management on dam group of hydropower station,the synergy measurement of safety emergency management based on ANP and order parameter was put forward. The synergistic relationship of safety emergency management process for dam group of hydropower station was summarized based on literature analysis,and an index system for synergy measurement of safety emergency management on dam group in hydropower station was established,which included5 subsystem,11 order parameters and 33 secondary indexes. The weight of each index was determined by using super decision software,and by using the order parameter method,the synergy measurement was conducted on 4 links of safety emergency management,including prevention,preparedness,response and recovery. The method was applied on the dam group of cascade hydropower station in a domestic basin. The results showed that the synergy degrees of each subsystem in response and preparedness links of safety emergency management were the highest,while the synergy degree of overall system was low,so the optimization measures should be taken to improve the synergistic degree of the system.

Study on numerical simulation of sulfur deposition in horizontal bend

Abstract: The deposition of elemental sulfur in gathering pipeline will cause the problems of clogging and corrosion,and sulfur deposition is more prone to occur in the bend. For this reason,the method of numerical simulation was used to study the sulfur deposition in horizontal bend. Firstly,the Reynolds stress model was used to simulate the flow field. Secondly,the Lagrange particle trajectory model was used to track the sulfur particles. Then the factors affecting the deposition rate of sulfur particles in bend were studied. The results showed that the negative pressure zone and low velocity zone would appear on the inner wall of bend. The gas velocity and curvature ratio would affect the flow field. The deposition rate of sulfur particles in bend would increase with the increase of velocity,particle size and curvature ratio. Sulfur particle deposition was the result by the combined effect of gravity and centrifugal force,and the centrifugal force was an important cause of the increased deposition rate in bend.

Mechanical analysis on buried pipeline under effect of surface tamping impact load

Abstract: In order to study the effect of tamping impact load on mechanical property of buried pipeline in the dynamic compaction operation of foundation,a three- dimensional model coupling rammer,pipeline and soil was established based on finite element principle. The variation regulations of section deformation and impact force of pipeline in the tamping impact process were analyzed,and the influence regulations of wall thickness of pipeline,tamping impact velocity and volume of rammer on the stress,strain and deformation of pipeline were studied. The results showed that the impact force received by the pipeline under the tamping impact load is pulse- type,and it reduces to zero over time gradually. The maximum impact force increases with the increase of wall thickness of pipeline,tamping impact velocity and volume of rammer. The maximum equivalent stress,the range of high stress and the maximum equivalent plastic strain of pipeline decrease with the increase of wall thickness,while increase with the increase of tamping impact velocity and volume of rammer. The section deformation rate of pipeline( ovality or sag ratio) increases with the increase of tamping impact velocity and volume of rammer,while decreases with the increase of wall thickness.

Analysis on response of overhead oil and gas pipeline impacted by rock-fall

Abstract: Aiming at the problem of rock- fall which influences the safe operation of oil and gas pipeline,based on the elastic- plastic mechanics,Cowper- Symonds constitutive model and finite element method,a calculation model of oil and gas pipeline impacted by rock- fall was established,and the dynamic response process of pipeline was numerically simulated. The parameter sensibility of impact velocity,radius of rock- fall,pipeline pressure and impact position of rock- fall was analyzed,and the influence rules of each parameter on the deformation of oil and gas pipeline were researched. The results showed that the impact energy of rock- fall is mainly used in plastic deformation of pipeline. In the impact process,the contact area between rock- fall and pipeline turns from elliptical spot to elliptical ring. The plastic deformation of pipeline increases with the increasing of impact velocity and radius of rock- fall,and it decreases with the increasing of pipeline pressure and deviation degree of rock- fall. The research can provide a reference basis for the safety assessment and protection engineering design of pipeline,and it has an important engineering significance to guarantee the safety transportation of oil and gas.

Experimental study on influence of particle size to combustion and explosion characteristics of sulfur

Abstract: The parameters tests on combustion and explosion characteristics of sulfur dust in wet forming process were conducted. Eight groups of sulfur dust with the mesh number of 16 to 35 mesh,35 to 60 mesh,60 to 80 mesh,80 to 100 mesh,100 to 120 mesh,120 to 160 mesh,160 to 200 mesh,and 200 mesh were selected,then four parameters including ignition temperature of dust layer,minimum ignition temperature of dust cloud,minimum ignition energy of dust cloud and lower explosion limit were measured,and the combustion and explosion characteristics of sulfur dust with different particle size groups were determined. It provides the basis for the making of monitoring standard on sulfur dust concentration in sulfur wet forming system.

Design and application of HSE information management system for construction enterprises

Abstract: In order to further standardize the daily business of HSE management,and give full play to the internal function of HSE management system,a Web system for HSE information management of construction enterprises based on B / S structure was constructed by applying. NET computer technology. This system took the HSE management system as the core,and it realized the unified HSE business management and reporting tools,information sharing,electronic filing of HSE material,data statistical analysis,personnel safety files management and other functions. Through the practical application,the HSE information management system played an important role in promoting the efficiency of HSE information management and improving HSE management level. Finally the problems existing in the system and suggestions for improvement were discussed,and it was pointed out that integrating into the PDA,Internet of Things and visualization technology can create more broad development space for the system.