共查询到20条相似文献，搜索用时 46 毫秒
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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
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声波测井在煤层顶板稳定性评价中的应用效果 总被引：2，自引：0，他引：2
通过测井技术,用获得的强度指数(R)来评价岩石强度,其结果与地质研究结论是一致的,也就是说,用声波测井可直接判断煤层顶板的稳定性。实践表明,越靠近煤田边界煤层顶板岩石强度指数越小,顶板也越不稳定,越靠近煤田中心部位煤层顶板岩石强度指数越大,煤层顶板也越稳定。 相似文献
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晋城矿区15#煤直接顶K2石灰岩厚8～12 m,结构致密坚硬,为坚硬难垮落顶板。针对厚层石灰岩顶板可能面临的大面积断裂和垮落,从而导致冲击地压等问题,通过岩石力学性质试验获得相关岩层力学参数,并运用关键层理论、数值模拟和相似材料模型试验,研究了厚层脆韧性石灰岩顶板的变形与垮落特性,得到了顶板初次来压步距20～25 m和周期来压步距10～15 m及垮落规律,并提出了顶板控制的技术途径,即初期中深孔爆破结合顶板关键层缓慢下沉综合控制技术。实践表明,厚层石灰岩顶板的垮落形态和垮落步距与理论和试验研究结果基本一致。该项成果为晋城矿区厚层脆韧性石灰岩顶板控制提供了有效途径。 相似文献
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邢台显德汪井田煤层顶板稳定性评价与预测 总被引：3，自引：0，他引：3
在分析影响显德江井田1号煤层顶板稳定性主要地质因素的基础上，采用综合指数法对煤层顶板稳定性进行了评价与预测，其结果将为采煤工作面顶板管理提供科学依据。 相似文献
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巷旁切顶打断了巷道与采场下位顶板的连续性,促进了采场顶板垮落形成碎石帮,深入研究切顶对采场下位岩层垮落特征的影响机制具有重要意义。对采场支架载荷进行了分析,并对上覆岩层建立了力学建模,明确了上覆岩层运动与典型位置采场支架载荷特征的关系。在此基础上,针对6个巷旁切顶的工作面,给出了典型位置支架的载荷数据,从而分析得到巷旁切顶对采场下位岩层垮落特征的影响机制。同时,建立了数值模型,分析了不同的切顶起始位置和下位顶板强度对下位岩层垮落特征的影响。结果表明,121工法的“垮落线”具有对称的弧形边界,110工法的“垮落线”在切顶侧向工作面充分移动,N00工法介于上述两者之间。此外,不同切顶起始位置和顶板强度条件下,切顶的作用效果存在差异。研究结果有利于进一步深化巷旁切顶对采场下位岩层垮落特征影响的认识。 相似文献
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河南登封煤田郜城井田二1煤层顶板为滑动构造形成的构造岩。通过对构造岩顶板测井曲线与其抗压强度指标关系的研究,明确指出,利用测井技术可以探测软弱岩体的力学性质 相似文献
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豫西诸煤田主采煤层二1煤层顶板非原生顶板,而是滑动构造的滑覆体。其由下而上可分为断层带、破碎带、裂隙带。它的水文地质条件简单,但工程地质条件复杂。岩石破碎,力学强度指标较低,回采中顶板不易管理。按其稳定性可分为较稳定的、不稳定的和极不稳定的三类,且以后两类为主,对这些顶板管理的基本措施是:短工作面,控顶距,快速推进,及时放顶,正常循环,不放大炮。 相似文献
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煤田地质勘探阶段煤层顶板稳定性评价方法的初步探讨 总被引：1，自引：0，他引：1
本文讨论了在煤田地质勘探阶段利用现有勘探成果资料评价煤层顶板稳定性的原理，提出了单因素分析，二级模糊综合评判的研究方法。该方法简单、灵活，具有较高的实用价值。 相似文献
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First Joint meeting of the Geological Society of China （GSC） and the Geological Society of America （GSA） Brought together by the GSA International Section Chengdu, China in 17-19 June 2013. The abstracts are available online and can be downloaded for free. 相似文献
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Yang Sen Hua Xinzhu Yang Peng Liu Xiao 《Geotechnical and Geological Engineering》2021,39(7):5161-5172
Geotechnical and Geological Engineering - In order to determine the reasonable empty roof distance during roadway excavation, a mechanical model of the direct roof rock beam was established, and... 相似文献
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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
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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
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结合自然通风的基本原理和国外的一些建筑实例，分析了现代建筑屋顶在建筑各种自然通风系统中的作用，提出了屋顶应采取的相关构造措施，以节约建筑能耗，保护人类身心健康。 相似文献
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P. P. Nomikos P. V. Yiouta-Mitra A. I. Sofianos 《Rock Mechanics and Rock Engineering》2006,39(2):121-129
Summary. An analytical method is presented for the calculation of the load carrying capacity of two-dimensional asymmetric rock wedges
when the loading on the joint faces is non symmetric, such as the case of an asymmetric wedge formed in the roof of a circular
tunnel in an inclined stress field. The pull out force that causes yield at one of the joint faces is evaluated from formulae
based on the limiting equilibrium conditions assuming a purely frictional joint resistance. Next, the total pull out force
required for the secondary face to yield is calculated. During this step, the wedge is further displaced and while the primary
yielding face is plastically deformed, the other face is still in the elastic range until failure. Validation of the analytical
procedure is obtained with the UDEC code, which provides an implementation of the Distinct Element Method in two dimensions.
When the assumptions made in the analytical procedure are valid, the analytically calculated values for the pull out resistance
of the wedge are computed to be close to the numerically obtained ones. 相似文献
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Zhao Mengye Zhu Lei Huang Qingxiang Xu Kai Wu Yuyi Gu Wenzhe 《Geotechnical and Geological Engineering》2022,40(3):1429-1448
Geotechnical and Geological Engineering - Based on the S1201-2 large height mining in the 2–2 coal seam of Ningtiaota colliery with on-site microseismic measurement, physical simulation and... 相似文献
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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
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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