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1.
基于建筑屋顶面积大、无遮阳等具有可利用光伏屋顶发电的有利条件,本文以山西某市职中校区内的建筑物为例,从气象条件、系统运行方式、光伏电池方阵设计及并网电气设计等方面提出了综合优化设计方案。  相似文献   

2.
Creep Failure of Roof Stratum Above Mined-Out Area   总被引:1,自引:0,他引:1  
By taking into account the rheological behavior of the rock mass, the creep failure of a roof stratum seated on pillars in mined-out area is analyzed through a newly developed visco-elastic model. The time-dependent deflection of the roof stratum is obtained by numerical inversion of Laplace transform. The study shows that when creep properties of both the pillars and roof stratum are considered, the expected deflection in the roof stratum increases with time. Consequently, the roof would fail when the critical tensile stress is reached as the result of the increased deflection. To demonstrate the present analytical procedure, the failure time of roof stratum of the Xingtai Gypsum Mine in China was estimated, and the results obtained agreed with the observation. The case study indicates that the analytic approach provides a new way to assess the potential impact of the time-dependence of the roof stratum deformation and is useful in predicting its stability above a mined-out area.  相似文献   

3.
A new form of roof—”secondary roof structure” form, according to the characteristics of significant differences existing between the measured roof pressure and the roof pressure calculated by “support-surrounding rock” formulas, exists in working face that was mined under the upper gob at short range in Shendong mining area. The reasons why additional static load of secondary roof came into being were gained through the analysis of main roof weight distribution coefficient. It is that main roof can not transfer all the static load to the front coal wall and the rear caved gangue, and partial weight of the gangue of upper gob served as the additional static load attaching to the roof of working face. The roof parameters of five working faces mining under the upper gob were counted based on the field measurement and theoretical analysis. What is more, here, the relationship between the M/L value and the roof form was analyzed. Also the roof pressure of 21305 working face of 1?2 coal seam was calculated based on the secondary roof structure model, and the additional static load coefficient (T) was used as measurement of the additional static load of secondary roof. Finally, the directions which can be made a breakthrough in theoretical research of secondary roof were introduced.  相似文献   

4.
通过对潘谢矿区几起典型出水事故案例的分析,总结出工作面顶板砂岩出水具有出水时间短,水量迅速增大,储量以静储量为主等特点,分析了影响顶板砂岩涌水的主要因素(砂岩的发育厚度、埋藏深度、地质构造的影响、地下水对其补给的条件、煤层采动对覆岩的破坏程度、工作面的推进速度、钻孔的封闭质量等),并提出防治煤层顶板砂岩水害的综合措施.  相似文献   

5.
基于钻孔岩心资料,分析了芦岭煤矿8煤层顶板的岩性类型和顶板的结构类型,统计了顶板30m以内砂岩的厚度和8煤直接顶厚度。按照硬质岩石百分含量(K)的大小将顶板岩体岩性分为硬质岩体、中硬岩体和软质岩体三类;按照直接顶厚度/采高的比值(Km)将顶板的工程地质类型分为无周期来压顶板、周期来压顶板和周期来压强烈顶板三种类型,得出了8煤顶板类型分区。研究结果为该矿工作面布置方法、顶板支护方式的选择提供了依据,为顶板事故的预防提供了参考资料。  相似文献   

6.
瞬变电磁法在探测工作面顶板赋水性中的应用   总被引:4,自引:0,他引:4  
瞬变电磁方法对地下水反应敏感,而矿井瞬变电磁法具备距离目标体近,分辨率高的特点。为此使用加拿大产PROTEM47瞬变电磁系统,采用共面偶极方式布置线圈,对枣庄新安煤矿3上201工作面顶板赋水性进行了探查,指出顶板以上至70m高度的范围内(510~630m段),顶板含水裂隙发育,巷道顶部存在富水异常区,并得到了钻孔放水施工验证,为工作面安全回采提供了可靠的技术支持。井下疏放水和工作面回采资料表明,瞬变电磁法探测工作面顶板赋水性具有较高的准确性。  相似文献   

7.
采用热弹塑性模型,运用有限元软件,对煤炭地下气化的整个过程进行模拟,得出了煤炭地下气化过程中顶板岩层不同位置处的位移,并将其结果与传统煤炭开采的结果进行对比。结果表明:煤炭地下气化和煤炭开采过程中,顶板岩层移动曲线符合负指数函数关系;煤炭气化顶板岩层下沉速度比煤炭开采下沉速度快,且垂直位移较大;离煤层顶板越近,垂直位移越大,特别是直接顶位移急剧增大。  相似文献   

8.
龙固井田为全隐蔽的华北型煤田,位于巨野煤田中部,其首采扩大区主采煤层为3号煤层。考虑3煤层顶板稳定性主要受其顶板的构造信息和岩性信息影响,因此首先依据三维地震勘探综合解释成果及波阻抗反演解释成果对二者进行定量化,然后对波阻抗数据进行归一化处理,使得波阻抗数据和量化后的构造数据具有相同的变化范围及等量贡献。在此距离范围内构造和岩性的权值各为0.5,依此生成综合因素煤层顶板稳定性隶属度。分析3煤层顶板以上10m、20m处的综合因素煤层顶板稳定性隶属度图可以发现,该区3煤层顶板稳定性比较好。且其稳定性主要是受构造因素控制,岩性因素相对影响较小。  相似文献   

9.
Roof bolting in underground mining: a state-of-the-art review   总被引:1,自引:1,他引:1  
Conclusions With continuing investigations and developments, roof bolting today can in most cases successfully reinforce the mine roof in underground mining. In order to cope with the increasing use of roof bolts, efforts should be made to maximize the safety and minimize the cost. With regard to mechanical bolting, two important parameters need more advanced improvements and study, namely, optimum design of the shape and type of expansion shell and optimum bolt tension for a specific bolt pattern. For the fully grouted resin bolt, the most critical requirement is to develop a fast-setting, low-cost, intoxic, inflammable grouting material that can be used in the high speed mining cycle. It should be noted that geological conditions such as the strata type, rock properties,in situ stress, and planes of weakness play an important role in the successful application of any roof bolting system. These factors should be specified as accurately and quantitatively as possible in the design of any roof bolting system. Finally, proper and careful installation and continuous monitoring are imperative for the success of any roof bolting system.  相似文献   

10.
针对任楼煤矿开采72煤过程中,巷道在强大的动压作用下,破坏严重的情况,从岩性组成、岩层组合类型和顶板岩体结构三个方面,研究了煤层顶板岩体特征。研究结果表明,72煤顶板岩体岩性以软岩为主,岩层组合以"直接顶+老顶"的组合形式为主,岩体结构以碎裂和块裂结构为主。研究结果为巷道布置、支护形式选择、顶板管理提供了科学依据。  相似文献   

11.
理论分析与实际资料证实,煤层顶、底板反射波的干涉,在煤层厚度所产生的时差小于半个周期时,导致反射波的振幅随着煤层厚度的减小而减弱,且在煤层厚度较小(趋于0m)的情况下,仍然是可以连续对比追踪的;大于半个周期时,反射波的振幅与干涉效应无关。通过实际资料的分析计算发现,在煤层厚度趋于0m时,其顶、底板反射波的干涉所形成的振幅极限值仍然是砂、泥岩界面反射波振幅的3倍,依据这个特征可有效识别煤系地层中的薄、无煤带。  相似文献   

12.
利用自制的桩基物理模型,对溶洞顶板进行了一组模拟试验,通过受力分析认为顶板尺寸在跨高比与宽度比不是很大时,可以把顶板简化为简支梁进行计算,但是需乘以一个适当的系数,同时对顶板进行了变形分析,给出了顶板的三维沉降等高图以及试件表面形变图。  相似文献   

13.
口孜集勘查区矿井目前正处于开发阶段,深部煤层顶、底板的稳定性对煤层开采方法具有很大的影响。在分析煤层顶、底板岩性在平面上变化规律的基础上,结合岩石物理力学性质,对影响煤层顶底板稳定性的因素进行了研究。依据本区顶板岩石的单轴抗压强度,结合钻孔工程地质编录RQD值和煤层开采的采高比,对主采煤层进行了工程地质分类,其中13-1煤层顶板在东北部及中部以周期来压顶板为主,而8煤在东南及西北部也以周期来压为主。另外,对该区深部开采的工程地质问题进行了预测,根据预测结果提出了相应的预防措施。  相似文献   

14.
Depillaring of the existing pillars (square or rectangular in shape) by continuous miner provides irregular shaped ribs. An assessment of strength of such a rib becomes a difficult task. Literature review finds a number of approaches for the rib design but the scope of straight forward application of these approaches is limited due to the uniqueness of geo-mining conditions of the Indian coalfields. This review also finds that a wide spectrum of moderate roof conditions is yet to be properly addressed. Field studies at some depillaring operations in Indian coalfields indicated the influence of roof strata over the stability of a rib is considerably high. A systematic study of the roof strata influence on simulated models provided interesting results. A model for rib design is conceived on the basis of the simulation results. Discussing couple of field experiences of rib stability during mechanised depillaring under two different types of roof strata of Indian coalfields, this paper presents some results of the simulation along with the conceived model of a rib design.  相似文献   

15.
Reinforcing Coal Mine Roof with Polyurethane Injection: 4 Case Studies   总被引:2,自引:1,他引:1  
NIOSH has recently completed a study of the interaction between polyurethane (PUR) and coal mine roof in order to determine the mechanism of reinforcement, in both highly fractured rock and unfractured rock. Four case studies of PUR reinforcement are presented. At a West Virginia site, a borehole camera revealed the location of roof voids and guided the PUR injection. By injecting polyurethane into a zone from 0.6 to 1.8 m (2–6 ft.) high in the roof, a roof beam was created and ongoing intersection falls were halted. In another highly fractured roof in a western Pennsylvania mine, a total of 5.8 cm (2.3 in.) of rubbleized rock was found in a zone up to 3 m (10 ft.) into the roof. Untargeted PUR injection filled approximately 1/2 of the fractures. These two case studies showed that it is not necessary to fill up 100% of the void space to create stability. In the other two field sites, polyurethane was injected into weak, but unfractured roof. Post-injection video monitoring showed that weak bedding planes were hydraulically wedged open and polyurethane injected along bedding. The reinforcement value of this injection method is limited because of the wafer-thin layer of PUR introduced along bedding, and the lack of a PUR “webbing” which would serve as a structural framework to provide strength. It was determined that video inspection prior to PUR injection can aid in identifying the fracture zones to target, and minimize “blind” pumping and loss of PUR.  相似文献   

16.

In this paper, the behaviour of the pipe roof method with different pipe roofs disposition schemes including the pipe roof gate system and L-shaped system is discussed in terms of ground settlement reduction in the condition of underground space construction adjacent to the existing structure by using numerical simulation method. Considering the construction sequences of parallel underground tunnels with rectangular cross sections, the appropriate parameters and ground response characteristics of the corresponding pipe roof methods are evaluated by the ground surface displacement. The results indicated that the construction impacts from new buildings can be reduced by the pipe roof method. However, the theoretical performance of pipe roofs is highly dependent on the spacing between two structures. Generally, the L-shaped system is more effective in case of the distance (D) that is less than or equal to 1/2 width of box culvert (R) under the condition of a new structure constructed nearby the existing building. When two structures are constructed simultaneously, the excavation and the construction of structures influence each other reciprocally. The conclusions could provide a reference for the pipe roof method with the application scenario of adjacent building protection.

  相似文献   

17.
准格尔煤田含煤岩系高岭岩资源丰富,高铝矿物来源备受关注。采用高分辨率电感耦合等离子质谱等技术对石炭-二叠系太原组6号和山西组4号煤夹矸及顶底板中的稀土元素进行分析,并探讨了其物质来源。结果表明,6号煤夹矸及顶底板中稀土元素总量(ΣREY)均值为167.69μg/g,接近上地壳ΣREY值(168.4μg/g);4号煤夹矸及顶底板中ΣREY均值为210.22μg/g,高于上地壳的ΣREY值。4号煤夹矸及顶底板中轻稀土含量均值与6号煤相当,中稀土和重稀土含量均值为6号煤两倍以上。6号煤夹矸及顶底板分层样中δCe为0.82~0.94,δEu为0.53~0.87;4号煤中δCe为0.88~0.98,δEu为0.74~0.97;均为Ce、Eu负异常。6号煤层夹矸及顶底板稀土元素主要来源于盆地北西侧阴山地区元古界花岗岩和北东侧下古生界沉积岩。4号煤层夹矸及顶底板稀土元素物源主要为盆地北侧阴山地区下古生界和元古界的沉积岩和火成岩系。  相似文献   

18.
绿化屋顶的产流规律及雨水滞蓄效果模拟研究   总被引:3,自引:0,他引:3  
建筑物屋顶作为城市的"第五面",是城市立体化绿化的重要方面。通过屋顶绿化植被和土壤层的蓄滞作用,可在一定程度上延缓产流时间,减少城市径流,并改善局地微气候条件。开展了绿化屋顶的人工降雨径流观测实验,通过对降雨、径流的观测分析了绿化屋顶的雨水滞蓄效果。建立了描述绿化屋顶降雨产流过程的一维入渗模型HYDRUS-1D,利用实验数据进行了模型的率定和验证;并应用模型模拟分析了降雨频率、土层厚度和土壤类型等因素对绿化屋顶雨水滞蓄效果的影响。实验和模拟结果表明,绿化屋顶具有较好的雨水滞蓄效果,10cm土层厚度的绿化屋顶在不同降雨条件下的蓄滞量可达到16.1~21.6mm;随着土层厚度的增加,蓄滞效果更明显;就雨水蓄滞效果而言,壤土比砂土和粉粘土更适合于绿化屋顶。本研究成果可为城市屋顶绿化的推广应用提供参考。  相似文献   

19.
This paper focuses on the behavior of a roof sequence in the Appalachian Plateau of West Virginia, U.S.A., and emplacement of the Wills Mountain duplex with 17.5 km of displacement. Unlike the Plateau along strike in Pennsylvania and New York where forethrusting was previously documented, this roof sequence lacks an underlying salt-dominated roof décollement. Kinematic analyses reveal that the roof sequence in the West Virginian Plateau accommodated about two-thirds of the 17.5 km of shortening by the adjacent Wills Mountain duplex, as a forethrusting kinematic response. The remaining shortening imbalance of about 5 km between the duplexes and younger roof sequence rocks is accommodated by additional forethrusting further into the foreland and local compensation. This kinematic response matches that along strike in the central Appalachians despite the loss of the salt décollement. We interpret that an Ordovician shale-dominated formation was sufficiently weak to substitute for the salt horizon. Thus, a weak mechanical unit rather than specifically a salt décollement is a necessary prerequisite for forethrusting. A contributing factor to forethrusting may be the subvertical front of the Wills Mountain duplex, which inhibited other responses by the roof sequence. Mesoscale and smaller processes, including grain-to-grain pressure solution, twinning and cleavage formation account for over 75% of the shortening in the roof sequence, and, if ignored, would result in an erroneous interpretation of backthrusting or local compensation. This result suggests that failure to consider all deformation scales could lead to incorrect kinematic conclusions in other tectonic systems.  相似文献   

20.
基于数学形态学多尺度分析的顶板下沉量预测   总被引:1,自引:0,他引:1  
利用实测顶板沉降序列预测顶板下沉量是分析顶板稳定性的有效手段。提出基于数学形态学(MM)的预测方法,将沉降序列视为一组信号,用多尺度形态学算法将其解耦为若干分量,用最小二乘支持向量机(LSSVM)算法对各分量进行预测,叠加还原得到最终预测结果。根据某金矿762采场预控顶板AIII测点实测沉降时序,建立MM-LSSVM模型进行预测研究。研究结果表明,MM-LSSVM的解耦处理强化了各分量内部规律、弱化了相互干扰。与其他传统预测算法相比,MM-LSSVM的平均绝对百分误差和均方根误差大幅下降,预测精度显著提高。  相似文献   

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