Table of Content

28 July 2018, Volume 28 Issue 7

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Safety Livelihood Science Safety Systematology Safety Science of Engineering and Technology Safety Hygiene Engineering and Technology Safety Social Engineering Work Public Safety

Safety Livelihood Science

Study on relationship between controllers' cognitive behavior and fatigue based on EEG

WANG Lili, CHEN Fenglan

2018, 28(7):  1-6.  doi:10.16265/j.cnki.issn1003-3033.2018.07.001

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In order to quantify the effect of fatigue on controllers' cognitive behavior,32 on-the-job controllers were selected as testees to conduct experiments at 12:00 and 00:00 when the fatigue was cumulated to the maximum.EEG signals of the testees were recorded both before doing the experiments and during the time when they were doing radar simulator task involving large number of traffic and abnormal situations.A fatigue index was calculated based on EEG data .The reaction time of controllers to abnormal situations was used as an index of cognitive ability.The results show that the fatigue level at 00:00 is significantly higher than that at 12:00,and the fatigue index increases sharply after completing task at 00:00 with bigger fatigue risk.There is a linear relationship between the fatigue index before work and the reaction time to abnormal situations when working,and that the detection of fatigue before work can be used as a measure for managing controller fatigue risks.

Analysis of stress response characteristics of driver with cognitive distraction

LYU Aihong, MA Yong, LI Tengfei, ZHANG Yali

2018, 28(7):  7-12.  doi:10.16265/j.cnki.issn1003-3033.2018.07.002

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For the sake of preventing traffic accidents cognitive distraction may caused experimental trials were carried out to test the drivers' stress response under the two conditions: normal and cognitive distraction driving conditions.A driving simulator platform was used to simulate various stress scenarios such as city,town,mountainous area and highway,and collect driver operating data and vehicle driving data.A Facelab5 eye tracker was used to record the driver's eye movement data.The related characterization indicators were selected.And the experimental data was analyzed.The results show that compared with normal driving,cognitive distraction driving leads to a narrower visual search range for drivers.For both normal driving and cognitive distracting driving,the scanning scope is mainly medium and low.Cognitive distraction weakens the driver's ability to control the accelerator pedal.Compared to normal driving,cognition distraction increases significantly the driver's stress response time .

Safety Systematology

Research on lane keeping system based on improved algorithmfor optimal preview acceleration driver model

WANG Peiran, CHANG Lianyu

2018, 28(7):  13-18.  doi:10.16265/j.cnki.issn1003-3033.2018.07.003

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To solve the problem that the traditional lane keeping system has inadequate control precision and the driver model has insufficient adaptability to the road with large curvature,an improved algorithm for the optimal preview acceleration driver model is investigated by Taylor expansion at non-zero frequency point.The driving simulator data and the fast Fourier transformation (FFT) method were used to study the main steering frequency under double lane change.And a Simulink/CarSim co-simulation model was built as well.Double lane change simulation experiments were carried out.The results show that the lateral displacement error of the improved model is significantly smaller than that of original one,which the maximum displacement errors are reduced by 0.2,0.15 and 0.11 m for vehicle speeds of 60,70 and 80 km/h respectively,and that the improved driver model can control the vehicle to follow the expected path better than the road artificial potential field method.

Multidirectional ring network structure with one-way ring and its fault probability calculation

CUI Tiejun, LI Shasha, ZHU Baoyan

2018, 28(7):  19-24.  doi:10.16265/j.cnki.issn1003-3033.2018.07.004

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The tree topology is a special case of the network topology,that is,the SFT is a special form of the SFN.In order to study the relationships between system reliability and influencing factors,the tree representation of system structure in SFT theory is changed to network representation and SFN is established.The properties,basic structure of SFN and its transformation method to SFT are given.The SFN structure includes the general network structure,the multidirectional ring network structure and the multidirectional ring network structure with a unidirectional ring.Because of the particularity of unidirectional ring network structure,it has the characteristics of the cycle linkage fault and is unable to form a SFN alone.Therefore,unidirectional ring network structure is added to the multidirectional ring network structure to form a multidirectional ring network structure with a unidirectional ring.This paper focuses on the representation of the multidirectional ring network structure with a unidirectional ring and the method for calculating its fault probability.The results show that the constructed SFN can handle the fault process with network structure,and that SFN can be transformed into SFT,and then the SFT's existing theoretical method is used to complete the fault process analysis.

SD model of intervention strategies for habitual unsafe behavior of construction workers

HUANG Qinqin, QI Shenjun, ZHANG Yunbo, CHENG Jialei

2018, 28(7):  25-31.  doi:10.16265/j.cnki.issn1003-3033.2018.07.005

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For the sake of studying the effects of intervention strategies on habitual unsafe behavior of construction workers,and improving the safety of construction activities,the SEM-SD method was used to identify and intervene factors influencing construction workers' habitual unsafe behavior.Firstly,a SEM of habitual unsafe behavior was built to determine the path coefficients between the influencing factors and the intervention strategies.Then,the SD model was used to simulate the effects of intervention strategies on influencing factors.Study conclusion shows that as a result of implementing the intervention strategies,both the level of safety value and the level of safety ability of construction workers are raised significantly,the levels of unsafe psychology,unsafe physiology,and unsafe behavior show a parabolic form,i.e.they rise first and then decline,and habitual unsafe behavior of construction workers is effectively modified

Prediction of detonation velocity of nitro aromatic compoundsbased on quantitative structure-property relationship

HE Pei, PAN Yong, JIANG Juncheng, ZHOU Wei

2018, 28(7):  32-37.  doi:10.16265/j.cnki.issn1003-3033.2018.07.006

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In order to improve the accuracy of predicting detonation velocities of aromatic nitro compounds,a prediction method based on the QSPR principle was worked out.Molecular descriptors of 21 kinds of aromatic nitro compounds were calculated by using the Dragon software and 4 molecular descriptors relating the most closely to the detonation velocity of aromatic nitro compounds were selected from a large number of descriptors through GA-MLR method.A four-parameter linear theory model was built for predicting the velocities,and the degree of fitting,robustness and predictability were verified by means of the internal authentication method and the external validation method.The results demonstrate that the average absolute error (AAE) for the training set and test set is 0.048 and 0.208 km/s respectively,the root mean square error (RMSE) is 0.058 and 0.302 km/s,and that the effectiveness of the proposed method is great.

Safety Science of Engineering and Technology

Flame retardancy and pyrolysis kinetics of Pinus yunnanensisflame-retarded synergically by NH₄H₂PO₄ and borax

CUI Fei, YAN Long

2018, 28(7):  38-44.  doi:10.16265/j.cnki.issn1003-3033.2018.07.007

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In order to investigate the synergistic effect between phosphorous and boron elements,the flammability and pyrolysis characteristics of Pinus yunanensis with ammonium dihydrogen phosphate and borax were assessed by using limited oxygen index (LOI) method,wood stack method,cone calorimeter test and thermo-gravimetric (TG) analysis method,and the pyrolysis kinetics of the materials was analyzed by Kissinger and Flynn-Wall-Ozawa models.The results show that the combination of ammonium dihydrogen phosphate and borax has good synergistic flame retardant effect.When the mass ratio of ammonium dihydrogen phosphate to borax is 4∶1,the heat release rate(HRR),total heat release(THR) of the flame retarded wood are 62.8% and 56.5%,respectively,lower than those of untreated wood,and the LOI value reaches to 66.5%,and the combination of ammonium dihydrogen phosphate and borax improves the activation energy of Pinus yunnanensis calculated by Kissinger and Flynn-Wall-Ozawa methods,thus effectively enhancing the high-temperature stability,char-forming ability,and flame retardancy.

Numerical simulation study on dynamical evolution rule of spontaneous combustion oxidation zone and period

DONG Ziwen, QI Qingjie, HAN Guang, YU Wenhui, GENG Weile, PI Zikun

2018, 28(7):  45-51.  doi:10.16265/j.cnki.issn1003-3033.2018.07.008

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To explore the dynamic variation rule of the width of spontaneous combustion oxidation zone in goaf and the spontaneous combustion period in the process of mining,the 014N^-1₁,fully mechanized caving face in Ruian was taken as an object of study,a COMSOL Multiphysics dynamic numerical simulation model was built,based on deformation geometry and other physical-chemical fields theories.According to the model,the numerical simulation research on the spontaneous combustion in goaf was carried out.The results show that the greater the quantity of wind and the lower the mining velocity,the longer the time,the oxidation zone takes to appear for the first time,will be,and the shorter the spontaneous combustion period will be,that there is a S-shaped relationship between the maximum width of oxidation zone and time,that at the initial stage of mining,the oxidation zone width decreases with the increase of the quantity of wind.At the stable mining phase,the greater the quantity of wind,the wider the oxidation zone width will be,and that the faster the mining velocity,the lower the ratio of the maximum width of oxidation zone to the mining velocity will be,and the smaller the risk of spontaneous combustion will be.

Analysis of factors affacting steam explosion in semi-confined space

SHEN Zhengxiang, CHEN Hu, CHEN Dingyue, WANG Du, LYU Zhongjie, HUANG Fenglei

2018, 28(7):  52-57.  doi:10.16265/j.cnki.issn1003-3033.2018.07.009

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In order to investigate the mechanism of steam explosion in industry,an simulated experimental system for spontaneous explosion of massive molten aluminum and water in semi-confined space was designed.A high speed digital visualization system was employed to obtain the information on the explosive interaction under different conditions.The effects of the relative mass,the temperature,the vessel material and metal oxide on explosion were studied.The results show that the critical explosive condition and temperature have been obtained for explosion of massive molten aluminum and water in semi-confined space,that carbon steel with high wettability promotes base-triggered explosion,and the metal oxide with high water solubility also promotes explosive interaction,compared to non-metal oxide.

Numerical simulation of influence of wind velocity gradient ondeflagration characteristics of offshore flammable gas cloud

LIU Wenpeng, JIN Liang'an, GAO Zhansheng, YUAN Zhijiang

2018, 28(7):  58-63.  doi:10.16265/j.cnki.issn1003-3033.2018.07.010

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For the problems of flammable gas cloud formed by leakage in submarine gas pipelines and combustible gas transportation ships,based on the k-epsilon turbulence model and the eddy-dissipation model,numerical simulations of the formation and deflagration process of offshore flammable gas cloud were carried out under six wind velocity gradients (1-11 m/s),the specific influences of the wind velocity gradient on the deflagration pressure and temperature characteristics of gas cloud were studied.The results show that as the wind velocity gradient increases,the area of stable gas cloud decreases,the maximum pressure of deflagration decreases,the maximum temperature in the downwind low-altitude area decreases slightly,and the flame gradually moves away from the high-altitude area until completely stays in the low-altitude area,that in the low-altitude area,when the wind velocity gradient is 1 m/s,a large-area gas cloud and continuous high temperature cannot be formed,but when it is 3-11 m/s,a long-time and large-scale high temperature area will be formed easily.

Risk analysis of oil and gas release from FPSObased on scarce information

HE Rui, CHEN Guoming, LI Xinhong, SHEN Xiaoyu, XU Changhang, JIANG Shengyu

2018, 28(7):  64-69.  doi:10.16265/j.cnki.issn1003-3033.2018.07.011

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In order to solve the problem of evaluating the risk of accidents from oil and gas release in FPSO system under the condition of scarce data,a new methodology based on HBA was proposed for risk analysis of oil and gas release in FPSO.Firstly,a sequence model was built for FPSO leakage accidents based on the analysis of safety barrier and event tree.Secondly,on the basis of data on accident precursor and Bayesian inference,a new layer of estimation was added to the basic distribution parameters of the safety barrier and probabilities of FPSO oil and gas release accidents were obtained.Finally,the barrier failure probability in real time was updated to realize dynamic quantitative risk analysis for FPSO accidents.The results show that HBA can make full use of scarce data and add information priors from relevant data to obtain the posterior probability density distribution of each parameter,and that with the increase of time,the posterior probabilities tend to be stable and high,and the operation safety should be paid enough attention at the barriers' action which cause disasters and simultaneously prevent release accidents.

Allowable debonding strain limitation ofexternally CFRP-strenghtened RC beam

XU Junyan, ZHENG Binbin, LI Guibing

2018, 28(7):  70-75.  doi:10.16265/j.cnki.issn1003-3033.2018.07.012

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In order to further clarify the failure modes of RC flexural members strengthened with CFRP,and determine the accuracy of the formula for determining CFRP allowable debonding strain proposed by relevant codes,experimental tests were carried out to investigate the failure mode and tensile strain in CFRP laminates at initial debonding of CFRP-strenghtened RC beams which were simply supported and loaded under two points symmetrical loading.The results show that the main failure mode of the strenghtened beams is CFRP laminates debodning; the allowable debonding strains are 0.28-5.12 times of the tested tensile strains at initial debonding with a coefficient of variation more than 46%,and most of the code models highly overestimate the allowable debonding strain; the debonding of CFRP laminates of flexural strenghtened RC beam is related not only to the concrete strength,the amount of FRP laminates,and the modulus of elasticity,but also to the factors such as shear-span ratio,stirrup reinforcement ratio and longitudinal reinforcement ratio.

Research on slope relative stability criterion and its application in open-pit coal mine

WANG Dong, JIANG Juyu, LIU Shuai, HAN Xinping, CAO Lanzhu, SONG Ziling

2018, 28(7):  76-81.  doi:10.16265/j.cnki.issn1003-3033.2018.07.013

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The quantity and scale of slope landslide in soft rock open-pit mine is large,and it is difficult to prevent and govern the landslide,aiming at such a problem,the inclined soft rock slope of the southeast in Baiyinhua 1# open-pit mine is taken as the background,on the basis of the theory of limit equilibrium,the geometric shape of slope sliding body is determined,the method of obtaining index parameters of weak layer by back analysis of landslide deformation is given.FLAC^3D is used to reveal stress-strain evolution law and failure mechanism of rock and soil mass of the slope,the criterion of slope relative stability is proposed,the reasonable tracing distance and drawdown position are selected.The results show that: the stability of the slope in the southeast side of the mine increases with the increase of the width of the coal pillar,and decreases with the increase of the tracing distance.When the width of the coal pillar is greater than or equal to 180 m and the tracking distance is within the range of 50-300 m,the southeastern slope can be safely deepened.The width of coal pillar is 180 m and the tracking distance is 50 m,which can maximize the exploitation of resources.

Mechanical behavior and acoustic-charge inversion ofcoal rock under gas adsorption

XIAO Xiaochun, WANG Lei, WU Di, DING Xin, FAN Yufeng, ZHAO Baoyou

2018, 28(7):  82-87.  doi:10.16265/j.cnki.issn1003-3033.2018.07.014

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In order to further explore the mechanical behavior of coal and the inversion law of acoustic-charge under different gas adsorption pressures,and improve the method of predicting and warning of shock-outburst complex disaster,coal samples were selected from the 168 working face of Sunjiawan mine in Fuxin,and their mechanical properties,shock-outburst characteristics and acoustic-charge inversion process under different gas adsorption pressures were investigated by using an acomposite monitoring system of load-acoustic-charge-strain.The results show that with the increase of gas adsorption pressure,the impact tendency index of gas coal decreases,and the adjustment of stress before peak stress increases gradually,and the peak failure time of gas coal is prolonged,the degrees of internal damage,softening and breaking of coal sample also increase,and the dynamic disaster of gas coal likely changes from an impact into an outburst,and that the acoustic-charge high amplitude signal obtained from monitoring system has a good correspondence relationship with coal stress state in time series,and could reflect the mechanical characteristics of gas coal.

Effects of SDS on properties of gas extraction hole sealing material

SUN Wenbiao, GUO Bingbing, LU Qianming

2018, 28(7):  88-94.  doi:10.16265/j.cnki.issn1003-3033.2018.07.015

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In order to improve the sealing quality of gas extraction borehole in coal mines,a kind of new hole sealing material was developed with calcium sulphoaluminate,lime and gypsum as main components.The effects of SDS on properties such as setting time and strength were measured.The morphology of reaction product was observed with a scanning electron microscope(SEM).The chemical effect mechanism of SDS on sealing material was probed by measuring the ions concentration in the slurry filter liquor among others.The results show that after addition of SDS,the surface tension of the slurry decreases,and the setting time shortens,and the swelling stress increases,and the uniaxial compressive strength increases slightly at 6 and 24 hours but decreases significantly after 3 days.SDS accelerates hydration reaction of the material in early stages and leads to a smaller crystal size of hydration product,and SDS affects properties of the material via introducing .The physical function of drawing air bubble into the slurry and increasing the [OH^-] and Al content in the liquid phase of the slurry.

Effect of particle size on methane desorption from different metamorphic coal samples

YAN Jiangwei, WU Lei, WANG Junming

2018, 28(7):  95-101.  doi:10.16265/j.cnki.issn1003-3033.2018.07.016

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In order to reveal the effect of particle size on gas methane desorption from coal seam,physical simulation experiments were carried out the difference of gas desorption capacity and desorption.Differences between the cylindrical coal sample and the granular coal sample of anthracite (high metamorphic) coal and those of long flame coal (low metamorphic) in the effects on the gas desorption amount and the desorption rate were studied under different adsorption pressure conditions.The results show that there is a positive correlation between both the cumulative gas desorption amount and the desorption rate and the coal's metamorphism in the whole desorption process,that the cumulative gas desorption amount from granular coal is always greater than that from column coal,and the difference between the two increases first and then decreases,that particle size has an obvious effect on both the cumulative gas desorption amount and the desorption rate under the same metamorphic degree and pressure,and that the two granular coal sample grades of 0.5-1 mm and 1-3 mm are about to reach the limit of granularity in the desorption amount.

Theoretical analysis of coal seam gas pressure distributionaround drainage hole and its application

QI Liming, QI Ming, CHEN Xuexi

2018, 28(7):  102-108.  doi:10.16265/j.cnki.issn1003-3033.2018.07.017

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In the coal seam gas extraction technology,the distribution of gas pressure around the drainage borehole determines the optimal extraction time and extraction radius.In order to study the law of gas pressure distribution in coal seam around drainage borehole,an expression of gas flow around drainage borehole was worked out by theoretical analysis and numerical simulation,and an analytical expression of gas pressure around drainage borehole was deduced by applying Darcy's seepage law.The rate at which the gas extraction radius changes with the extraction time was taken as the basis for determining the best time for gas extraction,a critical value was obtained,and an engineering application was carried out.The results show that with the increase of distance between the measuring point and the borehole center,the gas pressure of coal seam increases gradually,and finally tends to the original value,with the extension of extraction time,the gas pressure decreases exponentially,the critical value of gas extraction radius changing with extraction time can be tentatively set at 0.47.

Research on key technologies for systematic control of gas in coal seam having low permeability and high outburst risk

FU Jiangwei, FU Xuehai, LIU Qi, JIN Xiaohua, CHEN Liang

2018, 28(7):  109-115.  doi:10.16265/j.cnki.issn1003-3033.2018.07.018

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Gas control is especially crucial in low-permeability and high-explosive coal seams.In order to improve mine safety as well as mining efficiency,based on comprehensive considering the speciality and difficulty of low-permeability and high-explosive coal seams,this paper proposes a systematic governance concept involving 8 key technologies:N₂ foam fracturing reservoir reconstruction,directional pin-shaped multi-branch horizontal well mining,butt well hydraulic migration and pressure relief mining,strip-type well up and down linkage pressure relief mining,regional progressive well up and down linkage extraction,well up and down linkage pumping mining system optimization,pressure relief zone gas drainage,and downhole drilling-cutting-pressure-flushing-injection integration.The research shows that systematic gas control is an effective way to ensure the safe mining of low-permeability and high-explosive coal seams,and that comprehensive considering the characteristics of a given coal mine production activity,predictive making plans for different stages and connecting them orderly are the key to the successful implementation of systematic gas control.

Stability study of roadway surrounding rock under influence of local weakening of structural plane

ZHANG Shukun, WANG Shuda, WANG Laigui, SUN Qi

2018, 28(7):  116-121.  doi:10.16265/j.cnki.issn1003-3033.2018.07.019

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In order to improve the supporting effect of roadway surrounding rock in the occurrence structure,the mechanical characteristics of local weakening zone formed by structural plane of roadway surrounding rock were taken as an object of study.On the basis of experiments carried out by the authors,relationships between strength,rigidity and stress-strain were obtained under the influence of structural plane.Based on the data on a certain the actual roadway support project,the influences of the local weakening zone formed by the structural plane on the strength,stiffness and stress-strain relationships of roadway rock mass were comprehensively analyzed under the combined action internal and external effects with theory.A method was put forward for controlling local weakening zone of roadway surrounding rock.The result show that rock specimen strength,rigidity and stability are controlled by local weakening zone formed by structural plane,that the position and shape of local weakening zone change with the internal and external factors,that the effect of confining pressure is better for rock specimen strength and stiffness when the structral plane inclination between 45° to 60°,that the closer to 60 °the angle is,the more greatly affected by the weakening zone,the strength,stiffness and stability will be,and the smaller the stability of surrounding rock will be.

Study on deformation of roof of ore rock contact zone roadway

LIU Xiaoyun, YE Yicheng, LI Yufei, LUO Binyu, LIU Yang, WANG Qihu

2018, 28(7):  122-128.  doi:10.16265/j.cnki.issn1003-3033.2018.07.020

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In order to analyze the influence of roadway roof deformation on the stability of contact roadway,taking the contact roadway in Daye iron mine as the research object,a mechanical model of the roof of contact roadway was established based on mechanical analysis,and the expression of the disturbance of rock beam of the roof of contact roadway was deduced.By using FLAC^3D software,the stress distribution and settlement amount of the roof of the contact zone roadway were analyzed,based on the field monitoring test,the accumulative settlement and settlement rate of the roof on both sides of the roadway in the contact zone were further analyzed.Research shows that the two groups of stress in the ore rock contact zone are concentrated locally,the roof and floor have the phenomenon of unloading,and the roof stress jumps fluctuatly in the contact zone.The roof subsidence of roadway is obvious,but the change of displacement nephogram is stable,and the range of displacement influence area is about 5.00 m around the contact band.The cumulative settlement and settlement rate of the side roof of the contact roadway iron ore are all smaller than those of the marble side.The settlement rate of the side roof of marble increases first and then decreases,and the deposition rate of the side roof of iron mine first increases,then decreases,then increases and then decreases.

Influence of rock anisotropy on well stress distribution and fracture pressure

XIA Boyi

2018, 28(7):  129-134.  doi:10.16265/j.cnki.issn1003-3033.2018.07.021

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A mechanical model was built for stress distribution across a horizontal well in shale.Analytical solutions to the model were developed and used to study the distribution and the impacts of mechanical properties,including Young's modulus and Poisson's ratio,on the fracture initiation pressure and fracture initiation angle.The results show that the degree of anisotropy in material coefficients strongly affects the effective stresses around the borehole and enhances the potential for borehole failure,and that Poisson ratio anisotropy does not affect significantly the fracturing pressure and angle for low anisotropy ratios,but it affects the effect of anisotropy in elastic modulus.

Study on influence of compression characteristics ofsuper-thick alluvium on mining subsidence

LI Xinling, GUO Wenbing, ZHAO Gaobo

2018, 28(7):  135-141.  doi:10.16265/j.cnki.issn1003-3033.2018.07.022

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In order to study the compression characteristics of super-thick alluvium and its influence on mining subsidence,triaxial compression tests were conducted on the surface cohesive soil in Jiaozuo mining area.Based on the experimental results,a numerical simulation of the mining subsidence of a certain working face under super-thick alluvium was performed.Mechanism of surface subsidence under super-thick alluvium was also analyzed theoretically.The results show that there is a compression phenomenon in alluvium and the compression amount increases with the increase of the thickness of alluvium,resulting in an increase in surface subsidence,and that the self-compression characteristics of the alluvium are the main factor resulting the large subsidence of surface when mining under super-thick alluvium.

Technology for enhancing supporting roadway surrounding rock influenced by frequent mining and its application

LI Guosheng, ZHANG Hui, JIANG Shuaiqi

2018, 28(7):  142-147.  doi:10.16265/j.cnki.issn1003-3033.2018.07.023

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In order to solve the problem of poor surrounding rock support in the roadway influenced by frequent mining,a joint reinforcement technology of "bolt anchor + shallow deep grouting" was developed.The technology involves cleaning surface,floating raft,shotcrete closure,grouting,brushing lane,anchor net support and shotcrete.The grouting design includes shallow hole grouting,deep hole grouting and grouting sealing schemes.The effect of the surrounding rock strengthening support technology was demonstrated by means of mechanical analysis and downhole engineering test.The results show that by using the joint reinforcement technology of "bolt anchor + shallow deep grouting",the broken coal rock masses in the surrounding rock are consolidated,the consolidation property is improved,and the anchor cables are anchored effectively,and that the amount of change of the roof from the layer is small during the period of 5 days,and then gradually tends to be stable.

Safety Hygiene Engineering and Technology

Effect of moisture of firefighter fabric onits thermal protective performance

ZHAI Shengnan, CHEN Taiqiu, JIANG Chunyan, FU Jiajia, WANG Hongbo

2018, 28(7):  148-152.  doi:10.16265/j.cnki.issn1003-3033.2018.07.024

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In order to determine the protective properties of thermal protective fabrics under humid conditions and improve the ability of fabric,firsly,the thermal protection fabrics were selected to form multi-layer combinations S-1 and S-2,the TPP and second-degree burn time of multi-layer fabrics combinations S-1 and S-2 were determined as a function of moisture of outer layers by using thermal protection performance test instruments.Then,a linear regression equation was established,and the changes in fabric thermal protection performance at four water cut rates were described.The effect of moisture of outer layer fabric on thermal protection performance of thermal protective clothing multilayer fabric was analyzed.The results show that for all the fabric combinations,there is appositive correction between the TPP or the second degree burn time and moisture of outer layers,that when the moisture of the outer fabric increases to about 30%,the moisture of the outer fabric directly affects the TPP of the whole fire fighting suit,and that the higher the moisture is,the better the TPP will be.

Safety Social Engineering Work

Research on statistical process control of metro construction workers'unsafe behaviors

GUO Shengyu, GUO Wenhui, GONG Peisong

2018, 28(7):  153-158.  doi:10.16265/j.cnki.issn1003-3033.2018.07.025

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To effectively reduce behavioral risks and prevent accidents in metro construction activities,an ISPC method was worked out based on intelligent video surveillance.Firstly,workers' unsafe behaviors were classified according to safety standards and operating procedures,and automatically recognized through camera-based behavior analysis functions.Secondly,the abnormal change signs of target unsafe behavior were found by the ISPC method during the process of dynamic intelligent video monitoring on site,and thus a real-time warning system was established.Finally,this method was applied to a certain station of Wuhan Metro.The results show this method can be used to monitor intelligently construction sites and control in time and effectively the development of unsafe behaviors.

A model for game between safety training provision of firm and worker' attendance to it in construction industry

WANG Xincheng, SUN Jide, ZHANG Zhaopu, WANG Haifeng, HUANG Yu

2018, 28(7):  159-164.  doi:10.16265/j.cnki.issn1003-3033.2018.07.026

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In the construction industry,there is a consensus among researchers and practitioners that construction workers have a little safety skillset.Aspects influencing firm' decision to provide safety skills training and construction worker's willingness to engage in this training program were explored through the lens of evolutionary game theory.What firm and worker focuse on were identified,and then a model was built for evolutionary game under the condition of government intervention,in which a dynamic relationship between firm's intent to offer a safety skill training program and worker's intent to attend that training program,was framed.Three ESSs were demonstrated for 9 game cases,as well as the requirements of every ESS.The results show that in the absence of government intervention,firm can not be expected to offer safety skills training to workers.In the case of government intervention,firm offers willfully a training program only when it benefits from that training,and as for workers,they are found to proactively engage in such a training program on the condition that they gain much more,not just a little,benefits.

Public Safety

Improved fuzzy Borda method based evaluation of expressway safety facilities

XUE Feng, ZHAO Lei

2018, 28(7):  165-171.  doi:10.16265/j.cnki.issn1003-3033.2018.07.027

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In order to provide decision-making reference for rational allocation of expressway safety facilities,an evaluation system of expressway safety facilities consisting of 15 indicators was established.An improved Borda combination evaluation method considering optimal solution and worst solution was worked out,the operational steps and numerical calculation methods of the method were given.5 expressways in Sichuan province were selected as samples,the technique for order preference by similarity to an ideal solution method and entropy value method,efficacy coefficient method,fuzzy synthetic evaluation and improved fuzzy Borda combined evaluation method were used to evaluate and compare the samples.The results show that Spearman rank correlation coefficients between the fuzzy Borda combination evaluation method and the four single evaluation methods are equal to or greater than 0.9,and the compatibility degree of the combination evaluation method is 0.98.It shows that the use of this method is highly credible.

Research on factors affecting agility of humanitarian logistics

LIAO Haiyan, TIAN Xiaoqiang, FENG Chun, ZHAGN Yi

2018, 28(7):  172-178.  doi:10.16265/j.cnki.issn1003-3033.2018.07.028

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The paper was aimed at improving the efficiency of humanitarian relief and reducing negative impacts of natural and man-made disasters.Literature research and expert interviews were adopted to extract factors influencing agility of humanitarian logistics.Based on ISM and MICMAC methods,a 5-layer hierarchical structure and a driving power-dependence diagram,in which all factors are separated into four clusters: autonomous,dependent,linkage and independent,were proposed to interpret how these factors impact agility of humanitarian logistics.Results show that resilience,reactivity,and cooperative capability are core competencies of humanitarian logistics agility,that the key to promoting agility of humanitarian logistics is improving autonomous factors such as resilience,rescue technology and contingency plan,and that more attention should be paid to infrastructure,social participation,etc.which are independent and root factors of humanitarian logistics agility.

Design and application of integrated platform for major natural disaster emergency rescue and support

PAN Donghua, YUAN Yi, WANG Dandan, ZHANG Chi, JIA Huicong

2018, 28(7):  179-183.  doi:10.16265/j.cnki.issn1003-3033.2018.07.029

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In order to solve the problem of low timeliness and unclear demand for major natural disaster relief,a major natural disaster emergency rescue platform based on B/S architecture was developed by the authors using GIS,simulation,internet of things,intelligent terminal and other technologies.The platform includes key functional modules for rapid assessment of major natural disaster losses and social impacts,rapid assessment of emergency response needs and capabilities, emergency aid dispatching and so on.It has been operating in National Disaster Reduction Center and more than 50 counties in Inner Mongolia,Shandong,Hainan and Yunnan.According to the actual application demonstration effect of these regions,the platform has played a decision-supporting role in the rapid assessment of major natural disaster losses and the needs assessment of emergency assistance.Its technical and functional framework has strong reusability and is of beneficial to the rapid promotion of the overall technical solution.

Petri-net based time analysis of emergency actions responding to industrial fires

LI Zicheng, ZHOU Jianfeng

2018, 28(7):  184-189.  doi:10.16265/j.cnki.issn1003-3033.2018.07.030

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In order to prevent domino effect triggered by fire in tank areas of petrochemical industry,an HCTPN based model was built for analyzing emergency actions responding to tank fires.The states of emergency response were represented by places,emergency actions by transitions,and changes of emergency states by flow of tokens in the net.Then,five different time patterns time serial gate,time output AND gate,time input AND gate,time output OR gate and time input OR gate,were proposed to analyze the time performance of the model.Finally,a tank fire was taken as an example,and the emergency response times were analyzed by using by the CPN Tools.The probabilities of domino effects were evaluated through the simulation analysis of the emergency response times.Two scenarios were discussed to analyze the impact of collaboration of emergency actions on fire escalation.The results show that the parallel mode of emergency actions is more time-saving and can prevent domino effect better than the serial mode,and that the model can be used to effectively analyze the time performance of emergency actions.