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公路隧道箱型预制仰拱变形破坏的模型试验研究

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浙江大学学报（工学版） 2024年第7期58卷 1417-1426页

作者：王迎超徐杭郝英周鑫刘泾堂李元海中国矿业大学深地工程智能建造与健康运维全国重点实验室江苏徐州221116 中国矿业大学力学与土木工程学院江苏徐州221116 甘肃省交通规划勘察设计院股份有限公司甘肃兰州730030

基于自主设计的新型箱型预制仰拱结构,采用室内物理模型试验,结合数字照相量测技术,研究该箱型预制仰拱的力学特性及破坏模式,通过数值模拟研究实际工况中衬砌与仰拱共同作用的受力规律.结果表明:竖向荷载作用下产生的拉张效应是预制仰... 详细信息

基于自主设计的新型箱型预制仰拱结构,采用室内物理模型试验,结合数字照相量测技术,研究该箱型预制仰拱的力学特性及破坏模式,通过数值模拟研究实际工况中衬砌与仰拱共同作用的受力规律.结果表明:竖向荷载作用下产生的拉张效应是预制仰拱裂纹产生及发展的主要原因,水平压力对预制仰拱的裂纹发展作用不明显.预制块接缝处以及各个预制块中柱转角处是预制仰拱结构的最薄弱部位,接缝处和转角处影响预制仰拱结构的安全.预制仰拱位移变化关于中轴部位呈对称分布,位移由大到小依次为中间预制块、左1预制块、左2预制块、左3预制块.箱型预制仰拱破坏可以分为加载压密、弹塑性变形和塑性破坏3个阶段.当仰拱与衬砌共同作用时,仰拱的上部主要承受拉应力,仰拱的下部主要承受压应力.试验结果表明,所设计仰拱结构具有良好的受力性能.

关键词：公路隧道箱型预制仰拱室内模型试验仰拱裂隙仰拱接头

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“精神传销”类犯罪的治理困境与应对策略

湖北警官学院学报 2024年第3期37卷 64-72页

作者：李远海李小波中国人民公安大学治安学院北京100038

作为当前新型传销犯罪的一种重要类型,“精神传销”通过洗脑方式使学员获得极大的精神满足,并依靠参与者的“自愿性”来发展下线、大肆敛财。当前,“精神传销”类犯罪快速发展并呈现出管理结构严密化、隐蔽能力趋强化、洗脑方式多样化... 详细信息

作为当前新型传销犯罪的一种重要类型,“精神传销”通过洗脑方式使学员获得极大的精神满足,并依靠参与者的“自愿性”来发展下线、大肆敛财。当前,“精神传销”类犯罪快速发展并呈现出管理结构严密化、隐蔽能力趋强化、洗脑方式多样化、危害结果社会化等特点。“精神传销”类犯罪治理面临监管识别难、侦查打击难、法律规制难、追赃维稳难等困境,可采取完善相关立法、加大监管力度、强化协作联动、加强宣传教育等策略,切实消除“精神传销”类犯罪的滋生土壤。

关键词：精神传销洗脑犯罪治理

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艾司氯胺酮预处理对小儿隐匿阴茎矫治术后早期不良行为发生的影响

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中山大学学报（医学科学版） 2024年第5期45卷 835-843页

作者：张欢孙盈盈夏寅李元海安徽医科大学第一附属医院麻醉科安徽合肥230022 安徽省儿童医院麻醉科安徽合肥230051

【目的】探讨艾司氯胺酮预处理对小儿隐匿阴茎矫治术后早期不良行为发生的影响。【方法】选择隐匿性阴茎矫治术患儿88例,手术时间小于1 h,年龄4~10岁,ASA分级I~Ⅱ级;采用数字表法随机分为艾司氯胺酮组(E组,n=44)和对照组(C组,n=44),E组... 详细信息

【目的】探讨艾司氯胺酮预处理对小儿隐匿阴茎矫治术后早期不良行为发生的影响。【方法】选择隐匿性阴茎矫治术患儿88例,手术时间小于1 h,年龄4~10岁,ASA分级I~Ⅱ级;采用数字表法随机分为艾司氯胺酮组(E组,n=44)和对照组(C组,n=44),E组麻醉诱导前20 min予以艾司氯胺酮0.5 mg/kg预处理,C组予以等量生理盐水静注,两组均采用喉罩静吸复合全身麻醉。在术前一天和入手术室时采用m-YPAS评估焦虑状态,记录诱导期ICC评分。分别记录诱导前(T0)、诱导后即刻(T1)、手术开始(T2)、入PACU(T3)、入PACU后10 min(T4)、出PACU前(T5)患儿的HR和MAP。记录苏醒期间PAED、FLACC评分。留取术前1天和术后第1天外周静脉血3 mL,检测MCP-1、Cortisol、Epinephrine水平。术后第3天、第7天对所有患儿行PHBQ问卷评分。【结果】E组术后第3天、第7天术后出现不良行为改变(NPOBCs)发生率明显低于C组(31.8%vs.63.6%,P0.05)。术后第7天,2组PHBQ中各项指标发生率差异均无统计学差异(P>0.05)。E组术后MCP-1明显降低,差异有统计学意义(P0.05)。多因素Logistic回归分析发现艾司氯胺酮和入手术室的m-YPAS是患儿术后早期NPOBCs的影响因素,且二者作为预测NPOBCs发生的ROC曲线下面积AUC(95%CI)分别为0.659(0.544,0.774)和0.918(0.849,0.988),敏感性分别为66.70%和92.90%,特异性分别为65.20%和84.80%,差异有统计学意义(P0.05)。【结论】艾司氯胺酮预处理可以降低接受隐匿性阴茎矫治术儿童的术后早期NPOBCs的发生,且可能与降低术后MCP-1有关,同时不增加围术期不良事件,安全性较高。

关键词：艾司氯胺酮焦虑术后不良行为改变儿童全身麻醉

基于计算机视觉的深部软岩巷道变形破裂特征试验研究

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中南大学学报（自然科学版） 2024年第9期55卷 3457-3468页

作者：赵万勇李元海于恒徐晓华中国矿业大学力学与土木工程学院江苏徐州221116 中国矿业大学深地工程智能建造与健康运维全国重点实验室江苏徐州221116

巷道破裂围岩大变形是深部煤炭开采过程中围岩稳定性控制的难点。针对该问题,本文通过大比例相似模型试验,采用自主研发的计算机视觉量测系统进行围岩全场精细化变形测量和破裂识别表征,探究了深部巷道围岩的碎胀变形演化特征。研究结... 详细信息

巷道破裂围岩大变形是深部煤炭开采过程中围岩稳定性控制的难点。针对该问题,本文通过大比例相似模型试验,采用自主研发的计算机视觉量测系统进行围岩全场精细化变形测量和破裂识别表征,探究了深部巷道围岩的碎胀变形演化特征。研究结果表明:裂隙的数量、长度和面积发育演化可分为径向裂隙发育和环向裂隙发育2个阶段;巷道围岩变形存在位移变化不一致现象,径向裂隙发育阶段以竖向位移为主,环向裂隙发育阶段以水平位移为主;在荷载作用下,有无支护结构巷道围岩均会发生剪切破坏,支护结构能够有效限制剪切破坏后围岩块体相互滑移错动,减小巷道的碎胀变形;深部巷道围岩变形破裂演化具体表现为巷道围岩沿结构面发生剪切破坏,产生径向裂隙切割围岩体;随荷载增加,围岩块体发生错动滑移,产生环向裂隙进而产生碎胀变形。

关键词：深部巷道模型试验计算机视觉碎胀变形裂隙演化

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Regulating bulkhead pressure of EPB shield machines through DEM modeling and data mining

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Underground Space 2023年第1期8卷 15-29页

作者： Panpan Cheng Fang liu Youjun Xu yuanhai li State Key Laboratory of Disaster Reduction in Civil Engineering Shanghai 200092China Key Laboratory of Geotechnical and Underground Engineering of the Ministry of Education Tongji UniversityShanghai 200092China School of Civil Engineering Inner Mongolia University of Science and TechnologyBaotou 014010China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhouJiangsu 221116China

Proper regulation of the earth pressure on the bulkhead of earth-pressure balanced(EPB)shield tunneling machines is significant to ensure safe *** study proposes a procedure for regulating the bulkhead pressure by combining numerical simulations and data mining,and applies the procedure to a metro line constructed in sandy pebble stratum using EPB ***,the relationship between the bulkhead pressure and the pressure on the tunnel face is carefully obtained from discrete element modeling,and the required supporting earth pressure is derived by considering the arching ***,aided with the machine learning method,a model is constructed for predicting the average bulkhead pressure per ring according to the operational parameters(i.e.,the average driving speed and the rotation speed of the screw conveyor).Given the target value of the bulkhead pressure,the optimal values of the operational parameters are obtained from the *** addition,an autoregressive moving average stochastic process model is developed to monitor the real-time fluctuation of the bulkhead pressure and guide the actions taken in time to avoid dramatic *** results indicate that the pressure difference between the tunnel face and the bulkhead is considerable,and the consideration of the arching effect can avoid overestimating the bulkhead pressure.A combination of the machine learning model and the stochastic process model provides a plausible performance in regulating the bulkhead pressure around the target value without dramatic fluctuation.

关键词： EPB shield machine Bulkhead pressure Discrete element method Support vector regression Autoregressive moving average model

Experimental Simulation and Numerical Modeling of Deformation and Damage Evolution of Pre-Holed Sandstones After Heat Treatment

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Computer Modeling in Engineering & Sciences 2020年第2期122卷 633-659页

作者： Shuo Yang yuanhai li Xiaojie Tang Jinshan liu State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhouChina. School of Mechanics and Civil Engineering China University of Mining and TechnologyXuzhouChina.

The deformation and damage evolution of sandstone after heat treatment greatly influence the efficient and safe development of deep geothermal energy *** investigate this issue,laboratory confined compression tests and numerical simulations were conducted on pre-holed sandstone specimens after heat *** laboratory test results show that the failure modes are closely related to the heat treatment temperature,with increasing treatment temperature,the failure modes change from mixed and shear modes to a splitting *** cracks always initiate from the sidewalls of the hole and then *** failure process inside the hole proceeds as follows:calm period,particle ejection period,rock fragment exfoliation period and rock failure *** specimens have different final failure features for the entire rock after heat treatment,but have the same failure features inside the *** phenomena can be explained by numerical *** numerical simulations reveal that the failure modes in the numerical results agree very well with those observed in the experimental *** damage zone always occurs at sidewalls of the hole and then propagates to the entire rock affected by shear or tensile *** 20℃to 200℃,thermal effect may promote shear damage and restrain tensile damage,while from 200℃to 800℃,thermal effect promotes tensile damage and restrains shear ***,the damage zone near the sidewalls of the hole has the same distribution range and ***,the differences in the mechanisms due to increasing heat temperature are evaluated using scanning electron microscope(SEM)observations.

关键词： Pre-holed sandstone high temperature confined compression damage evolution numerical modeling.

Spatiotemporal evolution rule of rocks fracture surrounding gob-side roadway with model experiments

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International Journal of Mining Science and Technology 2016年第5期26卷 895-902页

作者： li yuanhai Zhang Qi lin Zhibin Wang Xiaodong astate Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining & Technology Xuzhou 221116 China School of Mechanics and Civil Engineering China University of Mining & Technology Xuzhou 221116 China School of Civil Engineering Southeast University Nanjing 210096. China Changsha Engineering and Research Institute Ltd. of Nonferrous Metallurgy Changsha 410011 China

A series of plane-strain physical model experiments are carried out to study the spatiotemporal evolution rule of rocks fracture surrounding gob-side roadway, which is subjected to the pressure induced by the mining process. The digital photogrammetry technology and large deformation analysis method are applied to measure the deformation and fracture of surrounding rocks. The experimental results indicate that the deformation and fracture of coal pillars are the cause to the instability and failure of the surrounding rocks. The spatiotemporal evolution rule of the rock deformation and fracture surrounding gob-side roadway is obtained. The coal pillar and the roof near coal pillar should be strengthened in support design. The engineering application results also can provide a useful guide that the combined support with wire meshes, beam, anchor bolt and cable is an effective method.

关键词： Model experiment Digital photogrammetry Gob-side roadway Spatiotemporal evolution rule Stability control and combined support

Experimental study on uplift mechanism of pipeline buried in sand using high-resolution fiber optic strain sensing nerves

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第4期14卷 1304-1318页

作者： Haojie li Honghu Zhu yuanhai li Chunxin Zhang Bin Shi School of Earth Sciences and Engineering Nanjing UniversityNanjing210023China Institute of Earth Exploration and Sensing Nanjing UniversityNanjing210023China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou221116China

Reliable assessment of uplift capacity of buried pipelines against upheaval buckling requires a valid failure mechanism and a reliable real-time monitoring *** paper presents a sensing solution for evaluating uplift capacity of pipelines buried in sand using fiber optic strain sensing(FOSS)*** pipe-soil interaction(PSI)was investigated through a series of scaled tests,in which the FOSS and image analysis techniques were used to capture the failure *** published prediction models were evaluated and modified according to observations in the present study as well as a database of 41 pipe loading tests assembled from the *** strain measurements of FOSS nerves horizontally installed above the pipeline were correlated with the failure behavior of the overlying *** test results indicate that the previous analytical models could be further improved regarding their estimations in the failure geometry and mobilization distance at the peak uplift *** typical slip plane failure forms,inclined shear bands star from the pipe shoulder,instead of the springline,and have not yet reached the ground surface at the peak *** vertical inclination of curved shear bands decreases with increasing uplift displacements at the post-peak *** large displacements,the upward movement is confined to the deeper ground,and the slip plane failure progressively changes to the *** feasibility of FOSS in pipe uplift resistance prediction was validated through the comparison with image *** addition,the shear band locations can be identified using fiber optic strain ***,the advantages and limits of the FOSS system are discussed in terms of different levels in upward PSI assessment,including failure identification,location,and quantification.

关键词： Pipe-soil interaction(PSI) Upheaval buckling Distributed strain sensing Image analysis Uplift resistance prediction Interfacial behavior

瑞马唑仑联合艾司氯胺酮对剖宫产手术麻醉效果和精神症状的影响

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临床麻醉学杂志 2024年第7期40卷 719-722页

作者：邵先红朱勃朗王纯辉常俊李元海安徽医科大学第一附属医院麻醉科合肥市230012 安徽省公共卫生临床中心

目的观察瑞马唑仑联合艾司氯胺酮辅助用药对剖宫产手术麻醉效果和精神症状的影响。方法选择在腰-硬联合麻醉下行剖宫产的足月妊娠产妇96例,年龄24~38岁,BMI 24~35 kg/m^(2),ASAⅠ或Ⅱ级。采用随机数字表法将产妇分为三组:瑞马唑仑联合... 详细信息

目的观察瑞马唑仑联合艾司氯胺酮辅助用药对剖宫产手术麻醉效果和精神症状的影响。方法选择在腰-硬联合麻醉下行剖宫产的足月妊娠产妇96例,年龄24~38岁,BMI 24~35 kg/m^(2),ASAⅠ或Ⅱ级。采用随机数字表法将产妇分为三组:瑞马唑仑联合艾司氯胺酮组(RK组)、艾司氯胺酮组(K组)和对照组(C组),每组32例。胎儿娩出后,RK组静脉注射瑞马唑仑0.1 mg/kg,然后静脉泵注艾司氯胺酮0.25 mg/kg(加生理盐水稀释至20 ml静脉泵注,30 min内泵完);K组仅静脉泵注艾司氯胺酮0.25 mg/kg(加生理盐水稀释至20 ml静脉泵注,30 min内泵完);C组给予等容量生理盐水。所有患者术毕行PCIA。观察胎儿娩出至术毕的麻醉效果(Ⅰ级,无疼痛感;Ⅱ级,有轻微疼痛感;Ⅲ级,有明显疼痛感)。记录术中高血压、心动过速、精神症状(眼球震颤、头晕、噩梦和幻觉)等不良反应发生情况。采用爱丁堡产后抑郁量表(EPDS)评估产妇术后1周和4周的抑郁状态评分及产后抑郁(PPD)的发生情况(EPDS评分≥12分)。结果与C组比较,RK组和K组术中麻醉效果Ⅰ级比例明显升高,Ⅲ级比例明显降低(P<0.05),术后1周和4周EPDS评分及PPD发生率明显降低(P<0.05)。与K组比较,RK组术中精神症状发生率明显降低(P<0.05),术后1周和4周EPDS评分明显降低(P<0.05)。三组高血压、心动过速发生率差异无统计学意义。结论瑞马唑仑联合艾司氯胺酮用于剖宫产手术可提高术中麻醉效果,降低术中精神症状等不良反应发生率,降低产后EPDS评分,改善PPD。

关键词：瑞马唑仑艾司氯胺酮剖宫产麻醉效果精神症状产后抑郁