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Sojourns of a type of Gaussian processes above high level u

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Chinese Science Bulletin 1998年第13期43卷 1140-1141页

作者： xie, shengrong Department of Mathematics Southwest-China Normal University Chongqing China

Presents an expression for Gaussian process above high level u. Assumptions; Theorem.

关键词： type high

弹−塑性基础边界两侧采空(留煤柱)基本顶板结构初次破断特征

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煤炭学报 2024年第5期49卷 2195-2211页

作者：陈冬冬李子健谢生荣何富连罗昱蒋再胜马翔李辉中国矿业大学(北京)能源与矿业学院北京100083

为了研究两侧采空留煤柱工程条件下基本顶板结构的断裂位态及工程指导意义,构建考虑实体煤弹塑性变形与两侧煤柱宽度及支撑能力弱化的基本顶板结构双塑化基础边界力学模型,基于有限差分算法与主弯矩破断准则系统计算了在非对称煤柱区和... 详细信息

为了研究两侧采空留煤柱工程条件下基本顶板结构的断裂位态及工程指导意义,构建考虑实体煤弹塑性变形与两侧煤柱宽度及支撑能力弱化的基本顶板结构双塑化基础边界力学模型,基于有限差分算法与主弯矩破断准则系统计算了在非对称煤柱区和长边实体煤区的断裂线形态、区位属性及整体位态特征,并从7个层面、横纵向4对区域与传统模型对比,阐明新模型所得新结论及工程意义。结论如下:(1)两侧非对称煤柱参数对长边实体煤区域的基本顶主弯矩及破断位置影响小,但分别显著影响煤柱区的主弯矩大小、位置及断裂形态。两侧煤柱区(较强/宽煤柱区+较弱/窄煤柱区)基本顶断裂线形态有3类演化模式,随基本顶厚度及弹模增大而煤柱宽度、支撑能力及悬顶跨度减小,其变化规律为:非对称的“连续单弧形+连续单弧形”→“连续单弧形+开口间断双短弧形”→非对称的“开口间断双短弧形+开口间断双短弧形”。(2)长边实体煤区基本顶的断裂线主要有3类区位属性,随基本顶厚度及弹模增大而实体煤的塑性区宽度、塑化程度及悬顶跨度减小,其演变规律为:断裂线在塑性煤体区(C-S式)→弹塑性煤体分界区(C-TS式)→弹性煤体区(C-T式);(3)考虑断裂线区位属性,随基本顶厚度和弹模增大而煤柱宽度、支撑能力及悬顶跨度减小的基本顶全区域破断模式及演变规律为:C-S式的■→C-TS式的■→C-T式的■→C-T式的■→C-T式的■。针对研究两侧采空(煤柱)基本顶板结构破断的3类力学模型,从7个层面对比了3类模型的重要区别,从横向4个区域(开采区域的前方与后方、两侧煤柱区)与纵向4个区域(非对称遗留煤柱下伏、下伏开采空间出/进煤柱/体)阐明了其重要工程作用。

关键词：遗留煤柱基本顶两侧采空弹−塑性基础板结构

Stability analysis and control technology of gob‑side entry retaining with double roadways by flling with high‑water material in gently inclined coal seam

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International Journal of Coal Science & Technology 2022年第4期9卷 147-164页

作者： shengrong xie En Wang Dongdong Chen Hui Li Zaisheng Jiang Hongzeng Yang School of Energy and Mining Engineering China University of Mining and Technology-BeijingBeijing 100083China Beijing Key Laboratory for Precise Mining of Intergrown Energy and Resources China University of Mining and Technology-BeijingBeijing 100083China Department of Civil Engineering University of British ColumbiaVancouverBC V6T 1Z4Canada Hebei Coal Science Research Institute Corporation Ltd. Xingtai 054000China

To ameliorate the defects of insufcient support resistance of traditional roadside flling bodies for gob-side entry retaining(GER),overcome the inability to adapt to the deformation of surrounding rock,and isolate the goaf efectively,a new type of high-water material as a roadside flling body for GER technology with double roadways was *** instability analysis and control technology of GER with double roadways by flling high-water material into a gently inclined coal seam were *** basic mechanical properties of the new high-water material were investigated through laboratory experiments,and their main advantages were *** reasonable width of the roadside flling wall of a high-water material was obtained by combining ground pressure observation and theoretical *** distribution characteristics of the stress and plastic zone of surrounding rock of GER after being stabilized by the disturbance of the working face were studied using numerical simulations,and the failure range of GER by flling with high-water material was *** on this,a coupling control technology of anchor cables and bolts+single props+metal mesh+anchor bolts is *** the coupling methods of arranging borehole peeping and observing the convergences of surrounding rock,the results demonstrate that GER with double roadways by flling with a 1.8-m-wide high-water material has a good control *** above research will play an active role in promoting the application of high-water materials in GER roadside flling.

关键词： High-water material Gob-side entry retaining with double roadways Stability analysis Gently inclined coal seam Control technology

Reasonable location of stopping line in close‑distance underlying coal seam and partition support of large cross‑section roadway

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International Journal of Coal Science & Technology 2022年第4期9卷 181-202页

作者： Dongdong Chen Yiyi Wu shengrong xie Fangfang Guo Fulian He Ruipeng Liu School of Energy and Mining Engineering China University of Mining&Technology-BeijingBeijing 100083China

Close-distance coal seams are widely distributed over China,and the coal pillars left by the overlying coal seams afect the retracement channel of the underlying coal seam in the stopping *** on the engineering background of close-distance seam mining in a coal mine,the reasonable position of the underlying coal seam's stopping line and the support method of the large section roadway during stopping are investigated using feld measurements,similar simulation experiments,and numerical *** are three types of location relationships between the stopping line of the underlying coal seam and the stopping line of the overlying coal seam:"externally staggered with the upper stopping line"(ESUL,stops mining under the overlying goaf),"overlapped with upper stopping line"(OUL),and"internally staggered with the upper stopping line"(ISUL,ISUL-SD for shorter internal staggered distances,ISUL-LD for longer ones).There are diferent stress arch structures in the overlying strata of the above three positions,and the stress arch evolution process exists in the process of ESUL→OUL→ISUL-SD→ISUL-LD:a front and rear double stress arch structure→the front arch gradually decreases→the front arch dies out,and the double arch synthesizes the single arch→the single-arch range expands→the nested double *** relationship between the stress arch structure and the position of the stopping line is evaluated as follows:(1)ESUL:the stress concentration in the roof plate of the retracement channel of the underlying coal seam is the highest,because the overburden block of the extensive collapse zone acts directly on the roof plate of the retracement channel,resulting in relative difculties in roof support.(2)OUL:although the retracement channel roof pressure is minimal,the overlying rock structure has the potential for rotation or slippage instability.(3)ISUL-SD:the pressure on the roof of the retracement channel is small and the overburden structure is stable,which is conduci

关键词： Close-distance coal seams Stopping line Stress arch structure Retracement channel Partition support

Failure analysis and control technology of intersections of large‑scale variable cross‑section roadways in deep soft rock

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International Journal of Coal Science & Technology 2022年第2期9卷 124-146页

作者： shengrong xie Yiyi Wu Dongdong Chen Ruipeng Liu Xintao Han Qiucheng Ye School of Energy and Mining Engineering China University of Mining and TechnologyBeijingBeijing 100083China Mine Safety Technology Branch of China Coal Research Institute Beijing 100013China

In deep underground mining,achieving stable support for roadways along with long service life is critical and the complex geological environment at such depths frequently presents a major *** to the coupling action of multiple factors such as deep high stress,adjacent faults,cross-layer design,weak lithology,broken surrounding rock,variable cross-sections,wide sections up to 9.9 m,and clusters of nearby chambers,there was severe deformation and breakdown in the No.10 intersection of the roadway of large-scale variable cross-section at the−760 m level in a coal *** there are insufcient examples in engineering methods pertaining to the geological environment described above,the numerical calculation model was oversimplifed and support theory underdeveloped;therefore,it is imperative to develop an efective support system for the stability and sustenance of deep *** this study,a quantitative analysis of the geological environment of the roadway through feld observations,borehole-scoping,and ground stress testing is carried out to establish the FLAC 3D variable cross-section crossing roadway *** model is combined with the strain softening constitutive(surrounding rock)and Mohr–Coulomb constitutive(other deep rock formations)models to construct a compression arch mechanical model for deep soft rock,based on the quadratic parabolic Mohr *** integrated control technology of bolting and grouting that is mainly composed of a high-strength hollow grouting cable bolt equipped with modifed cement grouting materials and a high-elongation cable bolt is developed by analyzing the strengthening properties of the surrounding rock before and after bolting,based on the Heok-Brown *** a result of on-site practice,the following conclusions are drawn:(1)The plastic zone of the roof of the cross roadway is approximately 6 m deep in this environment,the tectonic stress is nearly 30 MPa,and the surrounding rock is severely fractured.(2)The def

关键词： Deep soft rock Variable cross-section Roadway intersection Bolting-grouting integration New grouting material

Stability influence factors analysis and construction of a deep beam anchorage structure in roadway roof

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International Journal of Mining Science and Technology 2018年第3期28卷 445-451页

作者： xie shengrong Gao Mingming Chen Dongdong Sun Yanding Pan Hao Su Hai Lan Shizhong Faculty of Resource and Safety Engineering China University of Mining and Technology Beijing Key Laboratory for Precise Mining of Intergrown Energy and Resources China University of Mining and Technology School of Mechanics and Civil Engineering China University of Mining and Technology Yuwu Coal Industry Group Co.Ltd. Shanxi Luan Mining Group

Deep beam anchorage structures based on spatial distribution analysis of the cable prestressed field have been proposed for roadway roof support, Stability and other factors that influence deep beam structures are studied in this paper using mechanical calculations, numerical analysis and field measurements, A mechanical model of deep beam structure subjected to multiple loading is established, including analysis of roof support in the return airway of S1203 working face in the Yuwu coal mine, China, The expression of maximum shear stress in the deep beam structure is deduced according to the stress superposition criterion, It is found that the primary factors affecting deep beam structure stability are deep beam thickness, cable pre-tension and cable spacing, The variation of maximum shear stress distribution and prestressed field diffusion effects according to various factors are analyzed using Matlah and FLAC3DTM software, and practical support parameters of the S1203 return airway roof are determined, According to the observations of rock pressure, there is no evidence of roof separation, and the maximum values of roof subsidence and convergence of wall rock are 72 and 48 mm, respectively, The results show that the proposed roof support design with a deep beam structure is feasible and achieves effective control of the roadway roof,

关键词： Support structure Deep beam Maximum shear stress Influencing factors Stability control Roadway roof

Surrounding rock control mechanism of deep coal roadways and its application

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International Journal of Mining Science and Technology 2015年第3期25卷 429-434页

作者： xie shengrong Li Erpeng Li Shijun Wang Jinguang He Chongchong Yang Yafeng Faculty of Resource & Safety Engineering China University of Mining & Technology

Aiming at the surrounding rock control problem of mining and preparation entries in Xingdong mine with large mining depth, and the comprehensive control countermeasures including high pre-stress cable truss system, this study put forward powerful anchor support system and anchor cable adaption technology to surrounding rock deformation. Furthermore, the control measures possess the supporting performance with ‘‘primary rigid-following flexible-new rigid, and primary resistance-following yield-new resistance'', which suits deep roadway surrounding rock control. The mechanical model of truss anchor supporting roof beams was established, and the inverted arch deflection produced by the cable pre-stress with stress increment effect and roof beam deflection were obtained. And then the system working mechanism was illustrated. Finally, the surrounding rock support parameters were determined by means of comprehensive methods, and put into practice. The results show that surrounding rock deformation realized secondary stability after three months. The roadway sides convergence value was less than 245mm, and roof subsidence was less than 124mm. In addition, there was no expansion and renovation during service period.

关键词： Deep coal roadway Truss system Inverted arch deflection Equivalent uniform load Powerful anchor support

EXTREME VALUES OF SEQUENCE UNDER WEAK MIXING CONDITIONS

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Science in China,Ser.A 1986年第11期29卷 1121-1131页

作者：谢盛荣 Southwest China Normal University Chongqing

Following Leadbetter’s weak mixing conditions (1974), [1—4] were concerned with the study of extreme values in stationary sequences. In this paper, the author has extended those results further to more general sequences including the identity distribution sequence. However, the limit problems for the Gaussian sequence, in [2, 4, 5, 7] are just special cases of limit problems for some asymptotically independent sequences in this paper, so that some main results in [1—7] have been extended and improved. On the other hand, the sequence u_n(x) is not necessary in the usual form x/a_n+ b_n, it may even be a general monotone function, and so G(x) is not necessary for the distribution function. Therefore we have made the discussion more general.

关键词： Th EXTREME VALUES OF SEQUENCE UNDER WEAK MIXING CONDITIONS

The joint limiting distribution of maxima with random indexes and sums of normal sequence

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西南师范大学学报（自然科学版） 1998年第5期23卷 1-6页

作者： xie shengrong Department of Mathematics, Southwest China Normal University, Chongqing 400715

Ｒｅｃｅｎｔｌｙ，ａｎｕｍｂｅｒｏｆｐａｐｅｒｓｈａｖｅｓｔｕｄｉｅｄｔｈｅｊｏｉｎｔａｓｙｍｐｔｏｔｉｃｉｎｄｅｐｅｎｄｅｎｔｐｒｏｐｅｒｔｉｅｓｏｆ∨ｎ１Ｘｉａｎｄｎ１Ｘｉｏｆｗｅａｋｌｙｄｅｐｅｎｄｅｎｔｓｔ... 详细信息

Ｒｅｃｅｎｔｌｙ，ａｎｕｍｂｅｒｏｆｐａｐｅｒｓｈａｖｅｓｔｕｄｉｅｄｔｈｅｊｏｉｎｔａｓｙｍｐｔｏｔｉｃｉｎｄｅｐｅｎｄｅｎｔｐｒｏｐｅｒｔｉｅｓｏｆ∨ｎ１Ｘｉａｎｄｎ１Ｘｉｏｆｗｅａｋｌｙｄｅｐｅｎｄｅｎｔｓｔａｔｉｏｎａｒｙｓｅｑｕｅｎｃｅ｛...

关键词： joint limiting distribution maximum random index sum normal sequence