深部巷道围岩稳定性控制技术研究与实践

针对邢东矿深部巷道围岩大变形、支护系统严重损毁等矿压显现特征,在分析深部巷道变形破坏机制的基础上,认为改善浅部围岩力学性质、提高支护系统强度是控制深部巷道围岩变形破坏的有效途径,并据此提出了集强力锚杆索、钢管混凝土支架、滞后注浆加固技术于一体的联合支护技术,并阐述其控制机理。建立了钢管混凝土支架力学模型,得出新型钢管混凝土支架承载力及其对巷道承载体系提供的支护反力,并综合应用理论计算、数值模拟优化和工程类比等方法确定其控制方案。现场实践表明,采用该方案2个月后,围岩变形趋于稳定,两帮变形量小于150 mm,顶板下沉量为94 mm,底鼓变形量为79 mm,有效解决了深部巷道变形失稳问题,并为类似深部巷道围岩控制提供了理论和技术支撑。     

急倾斜厚煤层回采巷道联合支护技术

为解决急倾斜厚煤层回采巷道支护困难,基于大安山煤矿急倾斜煤层赋存特征,通过理论分析和数值模拟分析了+550水平2槽煤层巷道应力场和位移场分布规律,巷道表现出左帮和顶板变形量大,软帮上角应力集中问题.针对上述特征,提出了强化关键部位的锚网索加钢带联合支护方案,通过现场试验验证了方案的可行性.结果表明:采用锚网索加钢带支护方案后,巷道整变形量较小,各监测点巷道两帮移近量最大值为8 cm,围岩表面无破碎或突出现象,实现了急倾斜厚煤层回采巷道的有效控制.     

特厚煤层回采巷道顶板变形特征及控制技术

为了解决特厚煤层回采巷道顶板变形严重、支护困难等问题,通过现场观测和理论分析得出特厚煤层回采巷道变形因素及其特征,并利用FLAC3D数值模拟软件分析了在原支护和高强恒阻让压锚网索联合支护2种护巷方式下巷道围岩变形情况.研究结果表明:含软弱夹层的特厚煤层回采巷道自稳时间短,变形速度快,顶板破碎严重,塑性区破坏范围较大,巷道顶板整体变形明显;高强恒阻让压锚网索支护系统能够适应围岩高应力的特点,遏制顶板过度变形破坏,满足该地质条件下巷道顶板大变形的趋势.工程实践表明,高强恒阻让压锚网索支护时巷道顶板最大下沉量为206 mm,并且现场未出现锚杆(索)破断失效的情况,支护结构能够满足巷道顶板变形特征,保障综放工作面的安全高效生产.研究结果可为类似条件下的巷道顶板控制提供参考.     

孤岛工作面强烈动压巷道变形控制

为有效解决孤岛工作面巷道支护难题,以常村S6-5轨顺为工程背景,研究该巷道围岩变形破坏的机理,并对锚杆支护进行分析/然后综合注浆加固机理、壁后充填加固技术以及裂隙充填与压密技术等围岩控制手段,提出全长预应力强力锚杆、中空注浆锚杆及强力锚索组合支护方案.研究结果表明,锚杆锚索受力稳定,顶板下沉量控制在52 mm以内,两帮移近量控制在76 mm以内,围岩变形可控,支护方案可完全保证巷道安全使用.     

深部软岩大变形巷道锚注一体化支护技术及应用

为了研究深部软岩巷道变形机制及相应的控制对策,以金川煤矿8202工作面回风顺槽为研究对象,针对深部软弱破碎岩层条件下的巷道围岩控制问题,采用室内试验和现场实测与理论研究相结合的方法,揭示了裂隙发育岩体巷道及典型支护结构体的变形破坏机制,分析了巷道围岩裂隙发育,易吸水膨胀,锚杆支护潜力未有效发挥等造成巷道围岩变形破坏的因素。基于现场围岩支护体系受力与变形数据分析,并通过FLAC~(3D)数值模拟软件,对比分析不同支护方式下围岩变形破坏特征。提出了浅部注浆支护封堵围岩裂隙、锚杆锚索支护配合锚索梁形成多层组合拱的联合支护方式。确定了对巷道围岩破碎严重区段进行注浆,锚杆长度3 m,锚索长度9 m,挂梁锚索长度6 m,锚索梁长度3.8 m,采用11#工字钢,全断面采用W钢带及金属网护表的主要支护参数。结果表明:新方案实施后,巷道表面位移较原方案平均降低72.8%,顶板下沉量大幅度减小,该技术能够有效控制围岩大变形,维护巷道长期稳定。     

软弱破碎围岩运输巷道变形机理及修复支护

为解决井下软弱破碎围岩巷道的支护问题,以巴鲁巴铜矿580 m水平运输巷道为研究对象,对巷道稳定性进行监测,分析巷道的变形特征及其影响因素,认为应力集中、围岩软弱破碎、支护强度低以及水的影响是巷道变形的主要影响因素。对巷道变形机理进行研究,建立巷道力学模型,在此基础上结合现场实际提出"钢拱架+长锚索"联合支护方案。使用FLAC3D对修复前后巷道稳定性进行模拟分析。研究结果表明:修复后巷道应力集中区域远离巷道表面,巷道围岩塑性区域面积下降40%。对巷道进行修复并对其稳定性进行监测,60 d内巷道两帮最大收敛变形量为39 mm、顶板最大下沉量为50 mm,没有明显的底鼓发生,巷道变形得到有效控制。     

金能煤矿软岩掘进巷道变形破坏特征及控制技术研究

摘 要：针对软岩巷道围岩在掘进过程中呈现出的顶板下沉量大、两帮收敛严重等特点，为解决巷道围岩稳定性控制的难题，本文以某矿二采区1201工作面的运输顺槽为研究对象，基于工作面巷道工程地质条件，采用现场实测、数值模拟和工业性试验等方法，阐述了软岩巷道的变形破坏特征，提出了三种不同的围岩控制方案，利用FLAC3D软件模拟了该巷道围岩水平位移、垂直位移和塑性区分布情况，并进行现场测试，工程应用结果表明：“锚索+W钢带+U型钢+注浆”的支护方案效果明显，提高了围岩的承载能力，实现了巷道围岩的稳定性控制。     

复杂应力条件下软岩巷道的返修支护

针对魏家地煤矿1070巷道返修工程,分析了复杂应力条件下软岩巷道破坏机理.研究表明,导致1070巷道出现顶板下沉量大、底板严重膨胀、两帮位移大的主要原因是巷道埋深大,构造应力高,采空区矿山压力显现显著.确定锚注锚网联合支护作为1070巷道返修方案.监测结果表明,1070的返修支护方案合理,效果良好.     

松软复合顶板巷道锚固技术数值模拟

为解决镇城底矿22409工作面尾巷支护问题,应用RFPA~(2D)软件对松软复合顶板条件下煤体-煤体巷道和煤体-煤柱巷道在不同支护方案时围岩的变形破坏特征和支护效果进行了数值模拟研究。结果表明:松软复合顶板条件下,煤体-煤柱类型巷道相对于煤体-煤体类型巷道来说,围岩变形破坏严重,且支护难度大,应加大支护强度。该成果为确定和优化锚杆-锚索支护主要参数提供了依据。     

极松散煤层复合支护技术研究

针对巷道所处煤层松软、埋深大、蠕变变形难以控制的问题,以芦岭煤矿为研究背景,在分析芦岭煤矿巷道原支护变形大的基础上,提出"平顶棚+梁锚注+网布"的复合支护技术.运用ABAQUS软件对新支护形式蠕变前后的应力及位移分布情况进行仿真模拟,给出了巷道顶中、底中和帮部中点的蠕变位移曲线,并与现场监测数据进行了对比分析.结果表明:采用"平顶棚+梁锚注+网布"巷道围岩支护方案,能有效控制围岩的蠕变变形,巷道顶板最大蠕变量仅为4mm,两帮移近量为60mm,底臌蠕变量为174mm,巷道总变形量减小,现场监测结果与数值模拟结果十分吻合且在巷道开挖13 d后变形趋于稳定,满足安全生产的要求,为极松散煤层巷道围岩的加固及支护提供借鉴.     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

Perspherical Approaches for Electrons in Atoms and Charged Excitons in Quantum Wells

Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to     

Advances in broadband wireless communications under high-mobility scenarios

Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications （up to 574.8 km/ h test speeds or 380 km/h commercial speeds） in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.     

Wuhan University Journal of Natural Sciences TOTAL CONTENTS

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海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

Scale-based spatial data model for GIS

Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to