Electric-controlled pressure relief valve for enhanced safety in liquid-cooled lithium-ion battery packs

The liquid-cooled battery energy sto rage system(LCBESS) has gained significant attention due to its superior thermal management capacity.However,liquid-cooled battery pack(LCBP) usually has a high sealing level above IP65,which can trap flammable and explosive gases from battery thermal runaway and cause explosions.This poses serious safety risks and challenges for LCBESS.In this study,we tested overcharged battery inside a commercial LCBP and found that the conventionally mechanical pressure relief valve(PRV) on the LCBP had a delayed response and low-pressure relief efficiency.A realistic 20-foot model of an energy storage cabin was constructed using the Flacs finite element simulation software.Comparative studies were conducted to evaluate the pressure relief efficiency and the influence on neighboring battery packs in case of internal explosions,considering different sizes and installation positions of the PRV.Here,a newly developed electric-controlled PRV integrated with battery fault detection is introduced,capable of starting within 50 ms of the battery safety valve opening.Furthermore,the PRV was integrated with the battery management system and changed the battery charging and discharging strategy after the PRV was opened.Experimental tests confirmed the efficacy of this method in preventing explosions.This paper addresses the safety concerns associated with LCBPs and proposes an effective solution for explosion relief.

Effect of Dynamic Pressure Feedback Orifice on Stability of Cartridge-Type Hydraulic Pilot-Operated Relief Valve

Current research on pilot-operated relief valve stability is primarily conducted from the perspective of system dynamics or stability criteria,and most of the existing conclusions focus on the spool shape,damping hole size,and pulsation frequency of the pump.However,the essential factors pertaining to the unstable vibration of relief valves remain ambiguous.In this study,the dynamic behavior of a pilot-operated relief valve is investigated using the frequency-domain method.The result suggests that the dynamic pressure feedback orifice is vital to the dynamic characteristics of the valve.A large orifice has a low flow resistance.In this case,the fluid in the main spring chamber flows freely,which is not conducive to the stability of the relief valve.However,a small orifice may create significant flow resistance,thus restricting fluid flow.In this case,the oil inside the main valve spring chamber is equivalent to a high-stiffness liquid spring.The main mass-spring vibration system has a natural frequency that differs significantly from the operating frequency of the relief valve,which is conducive to the stability of the relief valve.Good agreement is obtained between the theoretical analysis and experiments.The results indicate that designing a dynamic pressure feedback orifice of an appropriate size is beneficial to improving the stability of hydraulic pilot-operated relief valves.In addition,the dynamic pressure feedback orifice reduces the response speed of the relief valve.This study comprehensively considers the stability,rapidity,and immunity of relief valves and expands current investigations into the dynamic characteristics of relief valves from the perspective of classical control theory,thus revealing the importance of different parameters.

Mechanical analysis of effective pressure relief protection range of upper protective seam mining

This paper analyzes the control mechanism of coal and gas outbursts and proposes the concept of an effective pressure relief protection range, based on the stress relief of the underlying coal-rock mass and the development of a plastic zone. Also this study developed a stress change and fracture development model of the underlying coal-rock mass. In addition, the stress and depth of fracture of any point in the floor were deduced with the application of Maple Calculation Software. The specific engineering parameters of the Pingdingshan No. 12 colliery were applied to determine the relationship between the depth of fracture in the floor and the mining height. The pressure-relief principle of the underlying coal-rock mass was analyzed while varying the mining height of the upper protective seam. The findings indicate that as the depth of fracture in the floor increases, the underlying coal-rock mass experiences a limited amount of pressure relief, and the pressure relief protection range becomes narrower.Additionally, the stress distribution evolves from a ‘‘U" shape into a ‘‘V" shape. A 2.0 m mining height of protective seam situates the outburst-prone seam, Ji_(15), within the effective pressure relief protection range. The fracture development and stress-relief ratio rises to 88%, ensuring the pressure-relief effect as well as economic benefits. The measurement data show that: after mining the upper protective seam, the gas pressure of Ji_(15) dropped from 1.78 to 0.35 MPa, demonstrating agreement between the engineering application and the theoretical calculation.

Pressure relief and structure stability mechanism of hard roof for gob-side entry retaining

In order to explore the pressure relief and structure stability mechanism of lateral cantilever structure in the stope under the direct coverage of thick hard roof and its impact on the gob-side entry retaining, a lateral cantilever fractured structural mechanical model was established on the basis of clarification for the stress environment of gob-side entry retaining, and the equation of roof given deformation and the balance judgment for fracture block were obtained. The optimal cantilever length was proposed based on the comparison of roof structural characteristics and the stress, deformation law of surrounding rocks under six different cantilever lengths by numerical simulation method. Double stress peaks exist on the sides of gob-side entry retaining and the entry located in the low stress area. The pressure of gob-side entry retaining can be relieved by reducing the cantilever length. However, due to the impact of arch structure of rock beam, unduly short cantilever would result in insufficient pressure relief and unduly long cantilever would bring larger roof stress which results in intense deformation. Therefore, there is optimal cantilever length, which was 7-8 m in this project that enables to achieve the minimum deformation and the most stabilized rock structure of entry retaining. An engineering case of gob-side entry retaining with the direct coverage of 10 m thick hard limestone roof was put forward, and the measured data verified the reasonability of conclusion.

Optimum location of surface wells for remote pressure relief coalbed methane drainage in mining areas

Based on engineering tests in the Huainan coal mining area,we studied alternative well location to improve the performance of surface wells for remote pressure relief of coalbed methane in mining areas.The key factors,affecting location and well gas production were analyzed by simulation tests for similar material.The exploitation results indicate that wells located in various positions on panels could achieve relatively better gas production in regions with thin Cenozoic layers,low mining heights and slow rate of longwall advancement,but their periods of gas production lasted less than 230 days,as opposed to wells in regions with thick Cenozoic layers,greater mining heights and fast rates of longwall advancement.Wells near panel margins achieved relatively better gas production and lasted longer than centerline wells.The rules of development of mining fractures in strata over panels control gas production of surface wells.Mining fractures located in areas determined by lines of compaction and the effect of mining are well developed and can be maintained for long periods of time.Placing the well at the end of panels and on the updip return airway side of panels,determined by lines of compaction and the effect of mining,would result in surface wells for remote pressure relief CBM obtaining their longest gas production periods and highest cumulative gas production.

Pressure relief, gas drainage and deformation effects on an overlying coal seam induced by drilling an extra-thin protective coal seam

Numerical simulations and field tests were used to investigate the changes in ground stress and deformation of, and gas flow from, a protected coal seam under which an extra-thin coal seam was drilled. The geological conditions were: 0.5 meter mining height, 18.5 meter coal seam spacing and a hard limestone/fine sandstone inter-stratum. For these conditions we conclude: 1) the overlying coal-rock mass bends and sinks without the appearance of a caving zone, and 2) the protected coal seam is in the bending zone and undergoes expansion deformation in the stress-relaxed area. The deformation was 12 mm and the relative defor- mation was 0.15%. As mining proceeds, deformation in the protected layer begins as compression, then becomes a rapid expansion and, finally, reaches a stable value. A large number of bed separation crannies are created in the stress-relaxed area and the permeability coefficient of the coal seam was increased 403 fold. Grid penetration boreholes were evenly drilled toward the protected coal seam to affect pressure relief and gas drainage. This made the gas pressure decrease from 0.75 to 0.15 MPa, the gas content decrease from 13 to 4.66 m3/t and the gas drainage reach 64%.

Principle and engineering application of pressure relief gas drainage in low permeability outburst coal seam

With the increase in mining depth, the danger of coal and gas outbursts increases.In order to drain coal gas effectively and to eliminate the risk of coal and gas outbursts, we used a specific number of penetration boreholes for draining of pressure relief gas.Based on the principle of overlying strata movement, deformation and pressure relief, a good effect of gas drainage was obtained.The practice in the Panyi coal mine has shown that, after mining the C11coal seam as the protective layer, the relative expansion deformation value of the protected layer C13 reached 2.63%, The permeability coefficient increased 2880 times, the gas drainage rate of the C13 coal seam increased to more than 60%, the amount of gas was reduced from 13.0 to 5.2 m3/t and the gas pressure declined from 4.4 to 0.4 MPa, which caused the danger the outbursts in the coal seams to be eliminated.The result was that we achieved a safe and highly efficient mining operation of the C13 coal seam.

Exploitation technology of pressure relief coalbed methane in vertical surface wells in the Huainan coal mining area

Exploitation technology of pressure relief coalbed methane in vertical surface wells is a new method for exploration of gas and coalbed methane exploitation in mining areas with high concentrations of gas, where tectonic coal developed. Studies on vertical surface well technology in the Huainan Coal Mining area play a role in demonstration in the use of clean, new energy resources, preventing and reducing coal mine gas accidents and protecting the environment. Based on the practice of gas drainage engineering of pressure relief coalbed methane in vertical surface wells and combined with relative geological and exploration en- gineering theories, the design principles of design and structure of wells of pressure relief coalbed methane in vertical surface wells are studied. The effects of extraction and their causes are discussed and the impact of geological conditions on gas production of the vertical surface wells are analyzed. The results indicate that in mining areas with high concentrations of gas, where tectonic coal developed, a success rate of pressure relief coalbed methane in surface vertical well is high and single well production usually great. But deformation due to coal exploitation could damage boreholes and cause breaks in the connection between aquifers and bore-holes, which could induce a decrease, even a complete halt in gas production of a single well. The design of well site location and wellbore configuration are the key for technology. The development of the geological conditions for coalbed methane have a significant effect on gas production of coalbed methane wells.

Pressure relief of underground ammunition storage under missile accidental ignition

Safety of underground ammunition storage is an important issue,especially during the accidental ignition of missiles.This work investigates the pressure and temperature distribution of the multi-layer underground ammunition storage with a pressure relief duct during the accidental ignition process of the missile.A large-scale experiment was carried out using a multi-layered restricted space with a pressure relief duct to simulate the underground ammunition store and a solid rocket motor to simulate the accidental ignition of the missile.The results show that when the motor gas mass flow increased by5.6 times,the maximum pressure of the ammunition storage increased by 5.87 times.At a certain motor flow rate,when the pressure relief exhaust area at the end of the relief duct was reduced by 1/2,the maximum pressure on the first layer did not change.But the rate of pressure relief was reduced and the time delayed for the pressure of ammunition store to drop to zero.In this experiment,when the motor ignition position was located in to the third layer ammunition chamber,the maximum pressure was reduced by 32.9%and also reduced the rate of change of pressure.In addition,for the experimental conditions,the theoretical analysis of the pressure relief of the ammunition storage is given by a simplified model.Based on the findings,some suggestions to the safety protection design of ammunition store are proposed.

An analysis on the effect of mining height and floor lithology on pressure relief of upper protective layers

In order to understand the effect of mining height and floor lithology at the upper protective layer face on the pressure relief of protected coal seams, this paper uses a numerical simulation method to model the pressure changes at protected coal seam during mining upper protective layer. The results show that the taller the mining height at the upper protective layer face, the greater the protection on protected coal seam due to the higher level of pressure release; the upper protective layer face with hard rock floor impedes the pressure release at the protected coal seam, which affects the overall effect of the pressure release at protected coal seam using the protective layer mining method.

Simulating Error-Opening of Pressure Relief Valves of a Station on a Continuous Undulating Oil Pipeline with Large Elevation Difference

For oil pipeline in mountain areas,high hydrostatic pressure in the pipeline may cause error-opening of pressure relief valves,and oil is discharged from the pipeline to the pressure relief tanks,bringing spilling-over risk of the pressure relief tanks.Therefore,simulating the error-opening situations of the pressure relief valves and investigating the oil discharge process are necessary for checking the possibility of the spilling-over accident and then proposing measures to improve the pressure relief system.This research focuses on a continuous undulating oil pipeline with large elevation difference and a station along this pipeline,which is named B station in this paper,is studied.By OLGA software,simulation model of the pressure relief system of B station is established,and the accuracy of the model is verified by reconstructing a real accident and making a comparison with the actual accident data.The maximum discharge rate reached 8284 m3/h when the pressure relief valve was opened by mistake in the inlet and outlet of the station.The accumulated filling time of the two pressure relief tanks is 200 s,which is in good agreement with the accident data.On this basis,for error-opening of the pressure relief valves at the inlet and outlet of B station,simulation is performed to investigate variations of the discharge velocity,discharge flow rate,accumulated discharge volume and ventilation volume of the vent valve.The discharge velocity is found to be over the maximum velocity allowed for safety consideration.According to the accumulated discharge volume,it is inferred that spilling over of the pressure relief tanks will be caused once error-opening of the pressure relief valve occurs.Also it is judged that the existing breathing valve can not satisfy the ventilation requirement in case of failure of the pressure relief valves.From these simulation results,it is proposed that increasing the number of vent valves,replacing the manual valves with electrically operated valves,and employing security control interlock protection program are improvement measures to guarantee safe,efficient and reliable operation of the pressure relief system at B station.

A Study on the Dynamic Adjustment of Pressure Relief Gas Drainage Drilling in Mined-Out Areas

With the development of coal mine equipment mechanization, the wide application of “hole instead of roadway” technology greatly reduces the cost of gas control engineering, but puts forward higher requirements for the effect of gas drainage. At present, the drainage effect of coal mine inspection boreholes is mainly evaluated by the drilling field, but the flow rate and gas concentration of each borehole in the drilling field are not the same, which causes the gas drainage effect not to be correctly mastered. In the present study, the pressure relief drilling in the goaf of the working face of a typical multi-coal seam group high gas outburst mining area was taken as the research object. Through the newly developed portable drilling inspection device, the pure amount of drilling drainage was investigated, and the drilling design was dynamically adjusted. The enhancement of the goaf pressure relief gas control effect ensures the gas safety of the mining face. At the same time, this improves the gas extraction rate and reduces the emission of greenhouse gases. If the data from the borehole investigation can be transmitted in real time and analyzed in big data, the optimal extraction negative pressure can be predicted through a regression algorithm. Under the control of the negative pressure of each borehole by the actuator, the extraction system can have the function of intelligent judgment.

Pressure Control of a Large-scale Hydraulic Power Unit Using π Bridge Network

The steady state and dynamic characteristics of pressure output of a hydraulic power unit are important to the hydraulic system behavior.Because of the compact structure,the B-half bridge resistance network is widely used in the pilot controlled pressure relief valves.However the steady-state pressure error might be unacceptably big in those pressure control systems.A constant pressure power unit is typically assumed in analysis of steady state and dynamic behavior of hydraulic systems.The flow-pressure relationship seems to be much complex,in particular when big flow variation takes place.In this paper,the π bridge hydraulic resistance network pilot stage is designed in order to get better flow-pressure characteristics.Based on the similarity of electrical circuits,the main factors influencing flow-pressure characteristics are analyzed.Moreover,the optimum diameters of both constant hydraulic resistor and dynamic resistor are proposed.Flow-pressure characteristics are compared with different constant hydraulic resistors,dynamic resistor and spring stiffness by simulations and experiments.Results of simulations and experiments show that flow-pressure characteristics depend very little on the spring stiffness in whole flow range.Good controlled pressure characteristics can be achieved with suitable constant resistors.Overshoot can be reduced with the small diameter of the dynamic resistor.Flow-pressure characteristics of pressure relief valve can be improved with a π bridge pilot stage.The proposed pressure control method will provide some positive guidelines and be helpful to design a high performance hydraulic system with large flow.

PRESSURE COMPENSATION METHOD OF UNDERWATER HYDRAULIC SYSTEM WITH HYDRAULIC POWER UNIT BEING UNDER ATMOSPHERIC CIRCUMSTANCE AND PRESSURE COMPENSATED VALVE

Based on the analysis of the-state-of-the-art of pressure compensation of underwater hydraulic systems （UHSs）, a new method of pressure compensation of UHSs, whose hydraulic power unit is in the atmospheric circumstance, is proposed. And a pilot-operated relief valve with pressure compensation is realized. The pressure compensation precision is guaranteed by direct detection. Its dynamic performance and stability are improved by a dynamic feedback. Theoretical study, simulation and experiment show that the pilot-operated relief valve with pressure compensation has a fine property of tracking underwater ambient pressure and meet the requirement of underwater ambient pressure compensation.

高瓦斯煤层大直径钻孔卸压增透瓦斯渗流时空演化机理

矿井瓦斯抽采面临抽采率低、有效抽采周期短、瓦斯预抽体积分数不达标等困境。为实现高瓦斯低透气性煤层的精准卸压增透,以顺和煤矿2404典型深井高瓦斯低透气性煤层工作面为研究对象,基于长时力学效应理论建模、COMSOL数值分析和现场试验等方法,构建了大直径钻孔卸压煤层瓦斯运移多场耦合模型,提出了大直径钻孔瓦斯有效抽采半径的判定指标——残余瓦斯压力不超过0.22 MPa,揭示了大直径煤层钻孔卸压增透机理及瓦斯运移规律:单一大直径钻孔煤层瓦斯压力呈以钻孔圆心为对称中心的椭圆分布,即由钻孔圆心向外瓦斯压力逐渐增加,随着抽采时间延长,抽采达标区域逐渐扩大。钻孔周边应力转移特征为:随着抽采时间增加,单一大直径钻孔周边点的垂直应力呈现先增后降趋势。进一步提出了高瓦斯低透气性煤层大直径钻孔卸压增透抽采技术。模拟确定了钻孔有效抽采半径,孔间距6.0 m、直径300 mm钻孔卸压增透效果最好,其两侧3.0 m内平均渗透率为1.58×10^(-15)m^(2),远大于初始值1.15×10^(-17)m^(2)。现场应用表明,大直径钻孔瓦斯抽采远优于普通钻孔,300 mm大直径钻孔瓦斯体积分数最大值为47.2%,75 mm原钻孔最大瓦斯体积分数最大值仅为10.6%,且大直径钻孔5.0%以上高瓦斯体积分数抽采天数提高了40.2%,有效解决了小直径瓦斯钻孔治理难题,为高瓦斯煤层高效精准卸压增透强化抽采提供了有效途径。

煤矿防冲钻孔机器人全自主钻进系统关键技术

针对高地应力矿井钻孔卸压作业智能化程度低的技术难题,总结分析了国内外钻孔卸压技术和装备的研究现状,指出研发高性能、高可靠、高效率的防冲钻孔机器人全自主钻进系统是破解冲击地压防治难题的重要发展方向。为此,凝练了影响钻进系统性能的“孔位精准识别、钻具姿态精确感知、无线电磁随钻智能检测、钻具运行状态智能识别和钻进系统精确控制”五大关键技术,并给出了解决思路和方法。针对在复杂恶劣环境下卸压孔的精确识别问题,设计了融合图像尺寸调节和多阶段训练模式的卸压孔图像样本扩充SinGAN模型,引入多层特征融合优化的FasterRCNN,构建了基于改进SqueezeNet轻量级网络架构的孔位识别模型,以实现卸压孔位的准确快速识别;针对钻具姿态精确感知问题,提出了基于改进梯度下降法算法优化无迹卡尔曼滤波的惯性测量单元(Inertial Measurement Unit,IMU)初始对准方法,设计了多个IMU的空间阵列布局方式,研究了基于BP神经网络的钻具姿态误差补偿方法,旨在提高钻具姿态的解算精度,实现精准钻孔卸压;针对复杂地质环境下钻进工况的精确检测问题,搭建了煤矿井下随钻测量无线电磁传输系统架构,探讨了微弱电磁波信号自适应调制和随钻高速双向电磁传输技术原理,研究了孔底地质参数、几何参数和工程参数的测量原理和实现过程;针对钻进系统运行状态识别问题,构建了钻进信号时域、频域、时频域的多域特征和深度网络高级特征提取架构,提出了钻进系统关键零部件健康状态评估和故障诊断技术,构建了基于改进蝙蝠优化长短期记忆网络的卡钻风险因子预测模型,实现对卸压钻具卡钻状态的准确预测;针对钻进系统的精确控制问题,分析了钻进系统的液压系统工作原理,构建了考虑煤岩性状的钻进系统精确控制方案,探讨了基于转矩和位置的钻进系统最优控制参数求解原理,旨在实现钻进回转系统和给进系统的智能协同控制和并行作业。

沿空留巷密集钻孔切顶机理及关键参数确定方法

为实现密集钻孔切顶条件下沿空留巷顶板结构安全稳定,研究正常情况与密集钻孔条件下顶板岩层结构受力状况,基于岩石断裂理论和弹性理论分析回采前后顶板密集钻孔孔间围岩受力分布及其破断过程,明确密集钻孔切顶机理及相邻钻孔的孔间集中应力相互作用机制,推导工作面端头弧形三角板结构巷道侧边界密集钻孔孔间围岩的拉剪应力计算公式。在此基础上,分析不同参数对孔间围岩所受拉剪应力的影响作用,提出沿空留巷密集钻孔切顶关键参数确定方法。研究表明:密集钻孔主要通过回采前后钻孔周围应力条件改变来增加钻孔围岩拉剪应力集中程度,引起孔间裂隙扩张联通,形成切缝线破断关键岩层。回采前钻孔主要受水平挤压应力影响,回采后钻孔受力逐渐转变为采空区顶板回转下沉产生的拉剪应力为主,钻孔孔间围岩状态随之由孔间围岩弱化阶段过渡到孔壁裂纹成形阶段,再转变为孔间围岩破断阶段。密集钻孔孔间围岩所受拉剪应力大小主要取决于关键岩层厚度及钻孔孔径与孔间距之比,与钻孔高度及间距成负相关,与角度及直径正相关。据此提出了密集钻孔关键参数确定方法,并根据龙滩矿3124 N工作面坚硬顶板条件设计了密集钻孔切顶留巷方案,确定钻孔长度为8.3 m,角度为15°,钻孔直径为48 mm,间距为500 mm。留巷后巷道顶帮变形可控且整体稳定性较好,由此可证明密集钻孔布置参数较为合理,密集钻孔关键参数确定方法有效可行。

底板动压巷道压裂弱结构体应力转移控制技术

为了满足煤矿安全生产的需要,许多巷道都会布置在煤层底板中,如部分运输大巷、排水巷道、瓦斯抽采巷道等。采动应力容易造成底板巷道围岩应力升高,加剧底板巷道围岩变形,造成支护永久失效、顶板下沉、巷道底鼓、两帮收敛等破坏。针对此,提出了在应力传递路径上实施水力压裂,在指定的区域制造出一定空间形态的水压裂缝网,形成压裂弱结构体,实现区域范围内的应力转移,从而降低巷道区域范围内的应力,控制巷道的围岩稳定性的控制技术,并通过理论分析及现场工程验证等方式,揭示了底板动压巷道压裂弱结构体应力转移的力学机制,建立了相应的力学模型,对压裂弱结构体的合理位置、范围等影响因素进行了求解。得出:(1)压裂弱结构体使局部应力场发生明显变化,出现应力升高区和应力降低区,应力降低区主要分布在弱结构体与采动应力连线的方向上,主要集中在一个拱形的范围内;由于膨胀效应,在与应力来源垂直的方向上产生应力集中,出现应力升高区。(2)最大主应力变化幅度与压裂弱结构体的长轴长L、短轴长H、到巷道的距离P、与巷道连线的水平夹角β、压裂层的强度C及内摩擦角α、压裂的损伤变量D等有关。其中到巷道的距离P对卸压效果影响最大,损伤变量D对卸压效果影响最小。(3)采用提出的计算方法设计了淮北矿业集团袁店一矿的103运输集中巷的卸压方案,工程应用结果表明,底板动压巷道变形速率明显减缓,验证了底板强动压巷道压裂弱结构体应力转移模型的合理性。

基于力学模型构建的留巷切顶高度确定与围岩控制技术

以顺和煤矿2401运输巷道沿空留巷为工程背景,分析巷道围岩结构特征,基于巷道局部空间结构稳定性,分别构建了沿空留巷未切顶与切顶力学结构模型,并以巷道不同切顶高度进行物理相似模拟试验。结果表明:巷旁采空区切落的矸石增加对关键块的支撑力,同时弱化关键块对直接顶悬壁端部挤压,巷旁支护阻力减少35.78%;随着切顶高度增加,巷道顶板采空区侧端部悬臂由F型缓慢过渡到大I型,同时大保护结构具有向上平移趋势,相比于未切顶1巷,4 cm切顶2巷、8 cm切顶3巷与16 cm切顶4巷叠加应力峰值分别下降9.38%,28.13%,25.00%。结合巷道顶板岩性,最终确定切顶高度为8.2 m,留巷段采用三列单体液压支柱作巷旁支护,长短锚索超前补强,巷道围岩稳定,较好满足使用要求。

矿震与冲击地压防治研究进展

矿震与冲击地压是采矿领域亟待解决的热点、难点和瓶颈问题,为了有效控制矿震与冲击地压,综述矿震定义与分类、矿压假说及矿震与冲击地压防治技术,回顾切顶卸压理论及其在中厚金矿采空区处理与卸压开采、中厚及以下煤矿沿空留巷中的应用,并比较其与110工法的差异。据此,给出矿震定义,指出矿震与冲击地压发生的条件类似,针对厚矿体开采提出深埋坚硬顶板控制爆破切槽放顶技术。研究表明:控制爆破切槽放顶技术仍然是未来矿震与冲击地压防治中释放并转移高地压的主要方法,它还可将深埋厚矿体的“砌体梁”简化成弹簧岩梁承载体系。