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Clinical effects of nonconvulsive electrotherapy combined with mindfulness-based stress reduction and changes of serum inflammatory factors in depression
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作者 Zhi-Wen Gu Chun-Ping Zhang +1 位作者 Li-Ping Chen Xiong Huang 《World Journal of Psychiatry》 SCIE 2024年第5期653-660,共8页
BACKGROUND Depression is a common and serious psychological condition,which seriously affects individual well-being and functional ability.Traditional treatment methods include drug therapy and psychological counselin... BACKGROUND Depression is a common and serious psychological condition,which seriously affects individual well-being and functional ability.Traditional treatment methods include drug therapy and psychological counseling;however,these methods have different degrees of side effects and limitations.In recent years,nonconvulsive electrotherapy(NET)has attracted increasing attention as a noninvasive treatment method.However,the clinical efficacy and potential mechanism of NET on depression are still unclear.We hypothesized that NET has a positive clinical effect in the treatment of depression,and may have a regulatory effect on serum inflammatory factors during treatment.AIM To assess the effects of NET on depression and analyze changes in serum inflammatory factors.METHODS This retrospective study enrolled 140 patients undergoing treatment for depression between May 2017 and June 2022,the observation group that received a combination of mindfulness-based stress reduction(MBSR)and NET treatment(n=70)and the control group that only received MBSR therapy(n=70).The clinical effectiveness of the treatment was evaluated by assessing various factors,including the Hamilton Depression Scale(HAMD)-17,self-rating idea of suicide scale(SSIOS),Pittsburgh Sleep Quality Index(PSQI),and levels of serum inflammatory factors before and after 8 wk of treatment.The quality of life scores between the two groups were compared.Comparisons were made using t and χ^(2) tests.RESULTS After 8 wk of treatment,the observation group exhibited a 91.43%overall effectiveness rate which was higher than that of the control group which was 74.29%(64 vs 52,χ^(2)=7.241;P<0.05).The HAMD,SSIOS,and PSQI scores showed a significant decrease in both groups.Moreover,the observation group had lower scores than the control group(10.37±2.04 vs 14.02±2.16,t=10.280;1.67±0.28 vs 0.87±0.12,t=21.970;5.29±1.33 vs 7.94±1.35,t=11.700;P both<0.001).Additionally,there was a notable decrease in the IL-2,IL-1β,and IL-6 in both groups after treatment.Furthermore,the observation group exhibited superior serum inflammatory factors compared to the control group(70.12±10.32 vs 102.24±20.21,t=11.840;19.35±2.46 vs 22.27±2.13,t=7.508;32.25±4.6 vs 39.42±4.23,t=9.565;P both<0.001).Moreover,the observation group exhibited significantly improved quality of life scores compared to the control group(Social function:19.25±2.76 vs 16.23±2.34;Emotions:18.54±2.83 vs 12.28±2.16;Environment:18.49±2.48 vs 16.56±3.44;Physical health:19.53±2.39 vs 16.62±3.46;P both<0.001)after treatment.CONCLUSION MBSR combined with NET effectively alleviates depression,lowers inflammation(IL-2,IL-1β,and IL-6),reduces suicidal thoughts,enhances sleep,and improves the quality of life of individuals with depression. 展开更多
关键词 DEPRESSION Nonconvulsive electrotherapy mindfulness-based stress reduction Serum inflammatory factors Clinical effect Hamilton Depression Scale
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Stress Relief Measurements in Young Adults and Adolescents—A Comparative Pilot Study with Different Relaxation Programs
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作者 Andrea Bevelaqua Claus Muss 《Open Journal of Preventive Medicine》 2024年第6期131-142,共12页
Background: Chronic stress is a emotional challenge. Constant pressure presents a serious risk of damage to mental and physical health and hence is associated with increased incidence of various diseases. The ability ... Background: Chronic stress is a emotional challenge. Constant pressure presents a serious risk of damage to mental and physical health and hence is associated with increased incidence of various diseases. The ability to cope with chronic stress may be a function of psychological resilience including intellectual capacities, but more so of external factors such as life experience and education. Adolescents are more vulnerable to chronic stress than adults. The measures introduced during the COVID-19 pandemic brought up major societal problems. As both children and adolescents lost their life anchors, the prevalence of stress in adolescents increased from 20% to 45%. Chronic psychological stress can impede the normal development of schoolchildren. It may cause anxiety, social withdrawal, interpersonal conflicts and aggression. This applies particularly to those in puberty, with the adolescent already facing unstable social bonds and elevated fear about the future. It is likely that the puberty cohort accounts for the dramatic increase in the prevalence of stress. Since it impacts public health, chronic stress among school-age children is increasingly taking on a socio-political dimension. Non-clinical stress intervention studies can investigate how to achieve stress reduction in school children. Methods: In a small pilot study, we analysed the effects of a training program with four different standard interventions, i.e. mindfulness training, progressive muscle reflection, autogenic training, and sound meditation. We obtained baseline scores of 10 stress-indicators, and re-tested after the interventions were performed. Results: The four applied interventions resulted in a reduction of 8 (out of 10) stress-indicators, such as “feeling stressed” or stress related symptoms (headaches, dizziness, sweating). This positive impact of the interventions significantly reduced “Fears about the future” (p Discussion: School children recognise the positive potential of stress reducing training or interventions. Our results provide evidence in support of integrating the training of relaxation techniques in the school curriculum. We propose that a larger study be undertaken to determine which methods would be most effective. 展开更多
关键词 stress in Children and Young Adults Comparison of Different stress relief Interventions in a Cohort of Pupils
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Effects of mindfulness-based stress reduction therapy on anxiety and depression in patients with maintenance hemodialysis:a meta analysis
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作者 Xiao-Xiao Yang Yuan-Yuan Chen Fan-Jie Meng 《TMR Integrative Medicine》 2020年第8期1-9,共9页
Objective:This study aimed to evaluate the effects of mindfulness-based stress reduction therapy on anxiety and depression in patients with maintenance hemodialysis.Methods:CNKI,VIP,WanFang,CBM,Embase,the Cochrane Lib... Objective:This study aimed to evaluate the effects of mindfulness-based stress reduction therapy on anxiety and depression in patients with maintenance hemodialysis.Methods:CNKI,VIP,WanFang,CBM,Embase,the Cochrane Library and PubMed databases were retrieved.Randomized controlled trials of intervention effects of mindfulness-based stress reduction combined with conventional hemodialysis education compared with conventional hemodialysis education on maintenance hemodialysis patients were collected.The retrieval period was from the establishment of the database to December 2019.Two researchers independently screened the literatures,extracted the data and evaluated the risk of bias in the included studies.RevMan 5.3 software was used for analysis.Results:A total of 9 studies,which comprised a total of 664 participants were included in the final meta analysis.The results showed that mindfulness-based stress reduction could reduce the anxiety of patients(SMD=?1.65,95%CI:?2.29 to?1.01),reduce the depression(SMD=?1.44,95%CI:?1.85 to?1.03).Conclusion:Mindfulness-based stress reduction therapy has positive effects on depression,anxiety in patients with maintenance hemodialysis. 展开更多
关键词 mindfulness-based stress reduction Maintenance HEMODIALYSIS DEPRESSION ANXIETY META-ANALYSIS
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Intervention effect of mindfulness-based stress reduction for psychological health among nurses:A meta-analysis
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作者 Yi-Yan Chen Xiang-Shu Cui 《TMR Integrative Nursing》 2020年第5期163-171,共9页
Objective:To systematically evaluate the effects of MBSR on psychological health intervention in nurses.Methods:The randomized controlled trial(RCT)and self-controlled trial(SC)investigating the application of mindful... Objective:To systematically evaluate the effects of MBSR on psychological health intervention in nurses.Methods:The randomized controlled trial(RCT)and self-controlled trial(SC)investigating the application of mindfulness-based stress reduction in nursing staff were retrieved from CNKI,WanFang,VIP,PubMed,Cochrane Library,Web of Science,EMBASE databases.The retrieval time was set from the establishment of the database to April 2020.The Review Manager 5.3 software were used for meta-analysis.Result:9 RCTs and 5 self-control trails were included with 1421,712 subjects in the experimental group and 709 subjects in the control group.The results of the meta-analysis showed that compared with the control group,mindfulness-based stress reduction therapy can effectively reduce the psychological symptoms of clinical nurses[SMD=-0.96,95%CI(-1.51,-0.38),P=0.001],reduces nurses'anxiety levels[SMD=-1.28,95%CI(-2.18,-0.38),P=0.005],relieve the nurse's depression[SMD=-1.08,95%CI(-2.15,-0.02),P=0.005],improve the mental resilience of nurse[SMD=7.05,95%CI(3.93,10.17),P=0.03],showing a statistical meaning.Conclusion:The mental health of nurses is often neglected by themselves and there is insufficient awareness that MBSR can improve mental health.There has been a debate about whether MBSR actually improves the mental health of nurses,so it is necessary to further explore this issue and seek better methods and opportunities for practice. 展开更多
关键词 mindfulness-based stress reduction therapy NURSE Psychological health Intervention effec META-ANALYSIS
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SIMULATION OF VIBRATION STRESS RELIEF AFTER WELDING BASED ON FEM 被引量:7
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作者 X.C. Zhao Y.D. Zhang +1 位作者 H.W. Zhang Q. Wu 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2008年第4期289-294,共6页
A finite element model is developed for the simulation of vibration stress relief (VSR) after welding. For the nonresonant vibration, the reduction in stress strongly depends on the amplitude of vibration. For the r... A finite element model is developed for the simulation of vibration stress relief (VSR) after welding. For the nonresonant vibration, the reduction in stress strongly depends on the amplitude of vibration. For the resonant vibration, the vibration frequency is the key for stress relief. The vibration frequency should be close to the structure natural frequency for the desired vibration mode. Only small vibration amplitude is required, which will be amplified during vibration. Vibration time does not have a major impact on vibration stress relief. When the amplitude of vibration stress relief is large, the treatment will be more effective. 展开更多
关键词 Residual stress Vibration stress relief SIMULATION
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Non-complete relief method for measuring surface stresses in surrounding rocks 被引量:4
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作者 张凤鹏 邱兆国 冯夏庭 《Journal of Central South University》 SCIE EI CAS 2014年第9期3665-3673,共9页
The measurement of surface stresses in surrounding rocks with the use of a relief method of annular hole-drilling was studied by numerical analysis. The stress relief process by hole-drilling was then simulated with t... The measurement of surface stresses in surrounding rocks with the use of a relief method of annular hole-drilling was studied by numerical analysis. The stress relief process by hole-drilling was then simulated with the use of finite element method. The influences of the borehole diameter(d), the initial stresses and the ratio of the initial principle stresses on the variations of the remained stress and the released stress in function of the relief depth(h) were discussed. The relation between the non-dimensional ratio of the released principle strains and that of the initial principle stresses, and the effect of the elastic modulus and the Poisson ratio of the rock mass on the stress relief curves were studied. The results show that the stress relief behavior formulated with the non-dimensional ratio of the released stress and the ratio of h/d is only sensitive to the ratio of the initial principle stresses and the Poisson ratio. The stresses are completely released when h equals 1.6d, and the tensile stresses take place on the bore core surface in the relief measurement process. Finally, a non-complete relief method of annular hole-drilling for measuring surface stress in surrounding rocks is proposed and the procedure is presented. 展开更多
关键词 non-complete relief method surface stress in surrounding rock stress relief rate ratio of initial principal stresses ratioof released principal strains
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TECHNOLOGY OF QUANTITATIVE ANALYSIS ON VIBRATORY STRESS RELIEF BASED ON ULTRASONIC TIME-OF-ARRIVAL METHOD 被引量:4
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作者 He Wen Ma Zhenyu Wang Xingli 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第3期461-463,共3页
The effect of vibratory stress relief (VSR) is usually evaluated with the indirect method of observing the change of amplitude frequency response characteristics of structures. A new kind of evaluating method of VSR... The effect of vibratory stress relief (VSR) is usually evaluated with the indirect method of observing the change of amplitude frequency response characteristics of structures. A new kind of evaluating method of VSR based on the ultrasonic time-of-arrival method (UTM), which can obtain the residual stress directly through measuring the propagation time of ultrasonic wave in the material, is presented. At first, the principle of the measuring method of residual stress based on UTM is analyzed. Then the measuring system of the method is described, which is in virtue of ultrasonic flaw detector and high-sampling-rate digital oscillograph. And a set of calibration system that contains a piece of standard specimen is also introduced. Experimental results prove the relation between the residual stress and the propagation time of ultrasonic in workpieces. Finally, the measuring and calibration systems are applied in evaluating the effect of VSR. The final test results show that the method is effective. 展开更多
关键词 Ultrasonic time-of-arrival method Residual stress Measure Vibratory stress relief
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Evaluation of residual stress relief of aluminum alloy 7050 by using crack compliance method 被引量:6
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作者 王秋成 柯映林 +2 位作者 邢鸿燕 翁泽宇 杨芳儿 《中国有色金属学会会刊:英文版》 CSCD 2003年第5期1190-1193,共4页
High strength aluminum alloys of 7xxx series have unacceptable levels of quenching residual stresses from solution heat treatment. The residual stress not only results in machining distortion and dimensional instabili... High strength aluminum alloys of 7xxx series have unacceptable levels of quenching residual stresses from solution heat treatment. The residual stress not only results in machining distortion and dimensional instability, but also increases the possibility of stress corrosion cracks. Therefore, it is necessary to reduce the residual stress to an acceptable level. The crack compliance method was adopted to study the influences of various stress relief methods on residual stress patterns in 7050 aluminum alloy. The results show that 90% residual stress can be eliminated by the cold stretching(Tx51) method. And a lower level of residual stress can be achieved by the uphill quenching(Tx53) method or the cold compression(Tx52). However, there is a very steep residual stress gradient normal to exterior surfaces. 展开更多
关键词 铝合金 残余应力 应力松弛 评价 破碎可塑性
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Research Findings Using Mindfulness-Based Interventions for Chronic Pain 被引量:2
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作者 Tracy L. Skaer 《Pain Studies and Treatment》 2015年第4期38-45,共8页
Chronic pain is a complex condition that is very detrimental to physical and psychological wellbeing. It carries a significant level of disability and economic burden. Pain patients frequently experience comorbid ment... Chronic pain is a complex condition that is very detrimental to physical and psychological wellbeing. It carries a significant level of disability and economic burden. Pain patients frequently experience comorbid mental illness (e.g. depression, anxiety, PTSD, insomnia) and often require psychotherapeutic interventions in addition to medication management. Mindfulness-based interventions (MBIs) have emerged as a means to treat several chronic conditions (e.g. chronic pain, depression, anxiety, substance abuse, stress, insomnia). The objective of this review is to evaluate the current research on the use of MBIs in chronic pain managment. Although there are several controlled trials on the use of MBIs in chronic pain management, only a few studies were found that demonstrated significant effects on pain intensity, quality of life, as well as physical and psychological functioning. Therefore, the current evidence is mixed and there are insufficient data to definitively confirm the full impact of the use of MBIs in chronic pain conditions such as fibromyalgia, chronic low back pain, rheumatoid arthritis, and chronic musculoskeletal pain. The lack of compelling evidence at this time signals a demand for higher quality investigations in this area. Research examining MBIs and concomitant CBT may be of great value in order to synergize and strengthen patient outcomes. 展开更多
关键词 CHRONIC PAIN FIBROMYALGIA CHRONIC Low Back PAIN mindfulness-based stress Reduction Acceptance and Commitment Therapy Depression Anxiety Quality of Life Psychiatric COMORBIDITIES
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Mindfulness-based cognitive therapy in the intervention of psychiatric disorders: A review
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作者 Jian-Fei Xie Jian-Da Zhou +2 位作者 Li-Na Gong Joanne DeSanto Iennaco Si-Qing Ding 《International Journal of Nursing Sciences》 2014年第2期232-239,共8页
Mindfulness-based cognitive therapy(MBCT)is frequently used for psychiatric disorders.Despite MBCT’s considerable potential for improving psychological health for patients,there is little empirical evidence to suppor... Mindfulness-based cognitive therapy(MBCT)is frequently used for psychiatric disorders.Despite MBCT’s considerable potential for improving psychological health for patients,there is little empirical evidence to support its practical application in Chinese.This review will define meditation and mindfulness,provide an overview of the development of MBCT,identify the evidence for the effectiveness of MBCT,and offer recommendations to medical personnels on how to provide support for patients receiving mindfulness intervention. 展开更多
关键词 ANXIETY DEPRESSION MEDITATION MINDFULNESS mindfulness-based cognitive therapy mindfulness-based interventions mindfulness-based stress reduction
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Influence of Cultural Alienation on Happiness of Overseas Students: Mediating Role of Stress Relief and Regulating Role of Cultural Intelligence
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作者 Xiaoxia Zhu Xu Guo +1 位作者 Yishu Teng John Gershenson 《International Journal of Mental Health Promotion》 2021年第2期289-302,共14页
When the global outbreak of new coronary pneumonia broke out in 2020,online public opinion events triggered by cultural differences among overseas students had come into the public view.To further explore the relation... When the global outbreak of new coronary pneumonia broke out in 2020,online public opinion events triggered by cultural differences among overseas students had come into the public view.To further explore the relationship between the cultural alienation of overseas students and their own happiness,this study takes visualization and analysis of positive,negative sentiment analysis of Weibo netizens’comment data in the“Xu Kexin Incident”as the starting point,on the basis of introducing cultural alienation,stress relief methods,and cultural intelligence,combining gender and social ability,social relations and other individual attributes,designed a questionnaire to investigate 502 overseas students,through the construction and analysis of the adjusted Cox risk ratio intermedi-ary model,comprehensive single factor interference and multi-factor cross-over comprehensive analysis.The results show that the cultural alienation of overseas students has a significant effect on their own well-being.The study concluded as follows:(1)Netizens hold polarized views on the three dimensions of overseas students’mask,safety,and culture;(2)Stress relief methods play an intermediary role between cultural alienation and the happiness of overseas students,among which Negative stress relief methods play a greater role;(3)The level of cultural intelligence regulates the intermediary process of stress relief methods.The higher the level of cultural intelligence,the stronger the regulatory effect. 展开更多
关键词 Cultural alienation HAPPINESS emotional analysis stress relief cultural intelligence
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A Numerical Investigation of the Stress Relief Zones Around a Longwall Face in the Lower Seam for Gas Drainage Considerations
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作者 Chunlei Zhang YPChugh +4 位作者 Ruimin Feng Yong Zhang Wei Shen Jingke Wu Yushun Yang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第4期135-157,共23页
Extraction of a protective coal seam (PVCS)-below or above a coal seam to be mined with the potential of coal andgas outburst risk-plays an important role not only in decreasing the stress field in the surrounding roc... Extraction of a protective coal seam (PVCS)-below or above a coal seam to be mined with the potential of coal andgas outburst risk-plays an important role not only in decreasing the stress field in the surrounding rock mass but alsoin increasing the gas desorption capacity and gas flow permeability in the protected coal seam (PTCS). The PVCSis mined to guarantee the safe mining of the PTCS. This study has numerically evaluated the stress redistributioneffects using FLAC3D model for a longwall face in Shanxi Province. The effects of mining depth, mining height andinter-burden rock mass properties were evaluated using the stress relief angle and stress relief coefficient. Verticalstress distribution, stress relief angle and stress relief coefficient in the PTCS were analyzed as the face advancedin the PVCS. The results showed that the stress relief achieved in different locations of the PTCS varied as the faceadvanced. Sensitivity analyses on the pertinent variables indicate that the stress relief in the PTCS is affected mostby the mining depth followed by the inter-burden lithology and the mining height. Furthermore, the elastic moduliof different layers within the inter-burden rock mass are more important than their uniaxial compressive strength(UCS) and Poisson’s ratio. These observations can guide gas drainage borehole design to minimize the accidentsof coal and gas outbursts. 展开更多
关键词 Methane drainage longwall mining protective/protected coal seam multiple seams FLAC3D software stress relief zones
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底板动压巷道压裂弱结构体应力转移控制技术 被引量:2
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作者 陈绍杰 刘江伟 +1 位作者 李亚康 吕华 《煤炭科学技术》 EI CAS CSCD 北大核心 2024年第1期106-116,共11页
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... 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。 展开更多
关键词 采动应力 弱结构体 水力压裂 卸压 切顶 围岩控制
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沿空留巷密集钻孔切顶机理及关键参数确定方法 被引量:4
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作者 刘少伟 李小鹏 +3 位作者 朱雯清 付孟雄 张定山 彭博 《煤炭科学技术》 EI CAS CSCD 北大核心 2024年第2期23-33,共11页
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... 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。 展开更多
关键词 沿空留巷 切顶留巷 密集钻孔 弧形三角板 孔间应力集中
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地面井分层卸压的煤系气合采原理及方式探讨
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作者 李瑞 金丽红 +1 位作者 夏彬伟 葛兆龙 《煤田地质与勘探》 EI CAS CSCD 北大核心 2024年第2期171-179,共9页
为了进一步认识制约煤系气合采的因素,提高煤系合层排采各产层的产气贡献,分别从动力、通道和气源条件出发,分析了煤系气合采的必备因素。基于改变地应力状态提高储层导流能力以及分层改变储层流体压力,满足多层合采动力条件的原理,提... 为了进一步认识制约煤系气合采的因素,提高煤系合层排采各产层的产气贡献,分别从动力、通道和气源条件出发,分析了煤系气合采的必备因素。基于改变地应力状态提高储层导流能力以及分层改变储层流体压力,满足多层合采动力条件的原理,提出了地面井分层卸压的煤系气合采方式。该方式通过在地面进行定向钻井,在目标储层中进行高压水射流作业,人工创造卸压空间(缝、槽、穴等),改变地应力状态,降低有效应力伤害,增加储层导流通道的数量和开度,提高目标储层压降传递速率。待储层压力降至符合煤系气合采动力条件时进行合层排采,从而提高煤系合采各产气层的产气贡献。相较于常规增产改造措施,此方式能够减少煤系气储层在有效应力作用下的储层伤害,且有助于提高储层压降传递效率,增强煤系气的解吸和扩散,降低多层煤系气合采过程中的层间干扰。在以上研究基础上,认为地面井分层卸压的合采方式主要适用于储层地应力大、产层间距小的煤系气储层,且有望在薄互层煤系气储层增产改造及层间干扰严重的叠合共生煤系储层开发领域进行应用推广。 展开更多
关键词 煤系气 分层卸压 多层合采 高压水射流 地应力 有效应力
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某跨声速风洞用980 高强度钢的去应力热处理工艺研究
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作者 任国柱 田富竟 唐淋伟 《热加工工艺》 北大核心 2024年第17期149-151,共3页
热处理是结构件制造的重要环节,与结构件的制造质量和使用性能紧密相关。对某型号跨声速风洞用980高强度钢去应力热处理工艺进行了研究,采用拉伸试验和-20℃低温冲击试验,对比分析了一次、二次去应力退火试验后980高强度钢的强度和韧性... 热处理是结构件制造的重要环节,与结构件的制造质量和使用性能紧密相关。对某型号跨声速风洞用980高强度钢去应力热处理工艺进行了研究,采用拉伸试验和-20℃低温冲击试验,对比分析了一次、二次去应力退火试验后980高强度钢的强度和韧性。结果表明,当去应力热处理工艺为去应力退火温度为(450±10)℃,保温时间为10~12 h时,跨声速风洞用980高强度钢材料可获得最优的强度和韧性。试验结果对同类材料的去应力热处理具有一定的借鉴意义。 展开更多
关键词 980高强度钢 去应力热处理工艺 强度 韧性
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首山一矿深部地应力分布规律及影响因素
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作者 郭德勇 揣筱升 +1 位作者 张铁岗 郭明生 《煤炭学报》 EI CAS CSCD 北大核心 2024年第5期2360-2375,共16页
为探讨平顶山首山一矿深部地应力分布规律及其影响因素,基于矿井实测地应力数据,运用构造物理学、岩石力学和数值模拟方法,研究了测点地应力类型、大小和方向分布规律,反演了地应力场分布特征,分析了埋深、岩性和地质构造对地应力的影响... 为探讨平顶山首山一矿深部地应力分布规律及其影响因素,基于矿井实测地应力数据,运用构造物理学、岩石力学和数值模拟方法,研究了测点地应力类型、大小和方向分布规律,反演了地应力场分布特征,分析了埋深、岩性和地质构造对地应力的影响,确定了影响地应力分布的主控因素。研究表明:多元回归反演分析法获得的地应力计算值与实测值吻合,相对误差小于20%,结果可靠。矿井煤岩体处于三维压应力状态,煤层主应力关系为S_(H)>S_(V)>S_(h),地应力由矿井北部向南部呈现先增大后减小再增大的变化趋势,地应力为28~44 MPa,属于高应力水平,地应力方向为NEE向。埋深影响地应力大小和类型,随埋深增加主应力增大,应力场类型向准静水压力场过渡;岩性与地应力密切相关,从泥岩到砂岩或灰岩,地应力增大,弹性模量越大地应力越大,地层岩性的差异造成地应力大小离散分布、应力方向偏转角不超过10°;矿井地应力与埋深、弹性模量的关系可表示为σ_(H)=0.0350H+0.4681E−8.5513。地质构造是影响首山一矿地应力分布的主控因素,褶皱形态控制地应力的水平应力分布,向斜内弧应力值大于背斜内弧,且褶皱弯曲程度越大,其内弧地应力越大,应力梯度越大;断层带内应力降低、断层尖灭端应力集中,地应力方向沿着断层走向偏转,与断层走向夹角越大,应力方向偏转角越大;断层切割复式褶皱时,断层与向斜构造组合区应力值大于断层与背斜构造组合区,且断褶构造组合造成地应力方向分布紊乱。 展开更多
关键词 地应力测量 应力解除法 构造物理 首山一矿
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基于隧道施工阶段地应力实测数据的岩爆判据研究
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作者 张士安 吴满路 +1 位作者 江蛟 冯亮 《防灾减灾学报》 2024年第3期1-9,共9页
云南省蔓金高速草果山隧道属于深埋长隧道,隧道围岩坚硬完整且脆性较高,隧道施工阶段面临着岩爆发生的风险。因此,采用应力解除法进行地应力测量,并基于实测数据结合现场岩爆发生情况与国内外不同的强度判据进行对比,并对岩爆判据的适... 云南省蔓金高速草果山隧道属于深埋长隧道,隧道围岩坚硬完整且脆性较高,隧道施工阶段面临着岩爆发生的风险。因此,采用应力解除法进行地应力测量,并基于实测数据结合现场岩爆发生情况与国内外不同的强度判据进行对比,并对岩爆判据的适用性进行分析研究。最后,根据岩爆实际发生的情况和位置对岩爆判据进行验证分析,结果表明:岩爆预测标准除应力指标外,还应使用多因素指标进行综合判别;某种岩爆预测方法不能适用所有地下工程,应结合工程的具体情况,进行岩爆危险性评估,为工程提出岩爆防治措施。同时此研究成果为深埋完整硬岩的岩爆灾害分析预测和防控提供了参考依据。 展开更多
关键词 草果山隧道 地应力测量 应力解除法 空芯包体应力计 岩爆判据 岩爆分级
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松软煤层底板爆破致裂增透模拟试验研究及应用
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作者 高魁 王秘 +3 位作者 乔国栋 田宇 傅师贵 王有为 《煤炭科学技术》 EI CAS CSCD 北大核心 2024年第6期102-110,共9页
针对松软煤层爆破增透钻孔施工困难,爆破增透产生的裂隙不发育且易于重新压实的问题,提出在底板岩层开展爆破作业,达到松软煤层增透进而增加瓦斯有效抽采时间的目的。为了监测跨界面应力波传播规律及煤层损伤状况,在实验室构建了物理模... 针对松软煤层爆破增透钻孔施工困难,爆破增透产生的裂隙不发育且易于重新压实的问题,提出在底板岩层开展爆破作业,达到松软煤层增透进而增加瓦斯有效抽采时间的目的。为了监测跨界面应力波传播规律及煤层损伤状况,在实验室构建了物理模型并开展了煤层底板爆破相似模拟试验。同时使用数值模拟的研究方法对煤层底板爆破过程中煤、岩体内部的损伤及裂隙的演化过程进行补充。结果表明:松软煤层底板爆破裂纹沿爆破孔向四周岩体扩展,爆破孔位置和底板煤岩交界面以及煤层内部的破坏较为严重,产生跨界面损伤裂纹。爆炸应力波从松软煤层底板岩层传播到松软煤层时,岩体和松软煤体的交界面产生透射压缩应力波和反射拉伸应力波,透射波作用于松软煤体,使煤层裂隙增加;反射波反作用于岩体,在煤岩交界面形成交叉裂纹,使底板岩层裂隙和松软煤层裂隙贯通,有利于松软煤层的瓦斯垂向运移流动和卸压瓦斯抽采。潘一东煤矿现场应用表明,煤层底板爆破增透后瓦斯抽采纯量及其浓度快速上升,抽采纯量从0.06 m^(3)/min提高到1.46 m^(3)/min,增加了23.33倍;瓦斯浓度从爆破前的10.46%上升到45.50%左右,增加了3.34倍,并且长时间维持在较高水平。研究成果可为深部松软煤层瓦斯高效抽采提供理论基础和技术支持。 展开更多
关键词 松软煤层 爆破增透 裂隙演化 爆炸应力波 卸压瓦斯抽采
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跨断层切顶卸压自成巷顶板变形机理及控制技术研究
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作者 郭志飚 赵元欣 +3 位作者 杨东山 高敬威 尹松阳 蒯孝辉 《煤炭科学技术》 EI CAS CSCD 北大核心 2024年第6期14-28,共15页
针对跨断层切顶卸压自成巷顶板变形大不易支护的问题,以棋盘井煤矿东区11101工作面运输巷为工程背景,探究跨断层切顶卸压自成巷顶板变形机理,研究“切顶卸压+恒阻锚索”支护对跨断层切顶卸压自成巷顶板变形的控制效果。建立力学分析模... 针对跨断层切顶卸压自成巷顶板变形大不易支护的问题,以棋盘井煤矿东区11101工作面运输巷为工程背景,探究跨断层切顶卸压自成巷顶板变形机理,研究“切顶卸压+恒阻锚索”支护对跨断层切顶卸压自成巷顶板变形的控制效果。建立力学分析模型研究断层及切顶卸压自成巷顶板各相关参数对巷道直接顶应力的影响,将切顶卸压自成巷顶板变形过程划分为4个阶段,研究巷道顶板各阶段及总垂直位移量计算方法并给出计算公式,并将相关参数代入公式求解跨断层切顶卸压自成巷顶板垂直位移量;利用3DEC数值模拟软件建立跨断层切顶卸压自成巷数值计算模型,研究断层附近巷道顶板应力应变演化规律及恒阻锚索控制效果,研究结果表明:数值模拟上下盘巷道顶板变形数据与理论分析所得数据结果误差分别为1.14%、4.04%;恒阻锚索能够有效减小巷道顶板变形,与未使用恒阻锚索模型相比,上盘巷道切缝侧顶板垂直位移量减小至16.8%,下盘巷道切缝侧顶板垂直位移量减小至50.7%;上下盘巷道顶板在工作面回采过巷道测点断面过程中出现不同程度的应力集中,其中上盘巷道顶板的垂直应力集中值大于下盘巷道,分别为5.72 MPa和4.48 MPa;恒阻锚索通过减缓断层附近巷道顶板变形速率,待巷旁碎石帮充填完成后与碎石帮共同对巷道顶板变形进行控制;将11101工作面运输巷围岩位移监测数据与理论模型计算结果相比较,误差均在10%以内,证明“切顶卸压+恒阻锚索”支护方式对跨断层巷道顶板变形具有良好的控制效果。 展开更多
关键词 切顶卸压 跨断层开采 3DEC 顶板变形 应力应变演化 恒阻锚索
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