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1.
 为了准确实测出工作面开采后覆岩导水裂缝带发育高度,提出了含水层判断导高的新判据。新判据分析认为,利用井下导高观测仪观测导水裂缝带高度时,观测钻孔施工过程中若穿透覆岩上方含水层,使承压水从钻孔内泻出,则说明导水裂缝带未发育至含水层层位高度。因此,实际工程应用中,在对导高进行合理预计的基础上,根据含水层是否被破坏分析含水层与导水裂缝带的层位关系可以作为确定导高的新判据。结合多个矿井工作面导高观测实例,验证了新判据判断覆岩导高值更为准确合理,具有更高的安全性。  相似文献   

2.
煤层采出后,上覆岩层要发生破坏和位移,并具有明显的分带性,通常呈现垮落带、裂缝带以及弯曲下沉带。确定煤层顶板导水裂缝带高度可为顶板防治水、采掘工程布置、防水煤柱留设以及瓦斯抽采设计提供依据。由于开采技术的不断更新以及地质条件的差异,导致导水裂缝实际发育高度在不同矿区有较大变化,有些矿区的导水裂缝发育高度与规程中的预测公式的计算结果并不完全相符,因此需要对其进行现场实测确定实际发育高度。本文通过对荆各庄矿1196F回采工作面工作面布置导水裂缝带监测系统,浏览导水裂缝带发育过程、形态特征及导水裂缝带高度,现场监测显示其导水裂缝带最终发育高度为28~32m。  相似文献   

3.
采空区覆岩破坏高度监测分析   总被引:21,自引:2,他引:21  
利用覆岩破坏高度观测钻孔进行相关测试研究,根据现场钻孔冲洗液漏失量、钻孔水位变化以及井下彩色钻孔电视影像,探明了煤层开采后上覆岩层内垮落带和导水裂缝带的发育高度及其分布形态.  相似文献   

4.
为探测导水裂隙带发育特征及高度,以榆神矿区西南部30201工作面为研究对象,采用钻孔水文观测、岩芯地质、物理测井、直流电法、密集分布式光纤感测相结合的导水裂隙带探测技术以及数值模拟,对导水裂隙带发育高度及特征进行研究。结果表明:工作面裂隙带发育高度为135.00 m,裂采比为21.43,冒落带发育高度为66.38 m,冒采比为10.5,弯曲下沉带高度为94.87 m;呈现出沿工作面倾向导水裂隙带在巷道发育最小,在工作面中心位置发育最大的“拱形”形态,冒落带在工作面中心位置发育最大,在巷道位置发育最小的特征;数值模拟精度与建立模型的地质条件参数密切相关,数值模拟与现场实测结果基本吻合。  相似文献   

5.
针对工作面回采后覆岩导水裂缝带发育高度探测难题,为掌握地下开采引起的岩层移动规律和确定导水裂缝带高度参数,研制了顶板导水裂缝带多段封堵同步测漏系统,并详细介绍系统的主要结构、功能和操作步骤.该系统主要包括探测子系统、封堵子系统、供给子系统和推进子系统,实现了顶板钻孔多探测单元、任意角度、同步精准连续测量,且与普通注水系统相比,该系统中测试探头移动次数减少了2/3.以新宏煤矿21010工作面开采条件为工程背景,在理论预计和数值模拟的基础上,将该系统运用到实际工程中.顶板导水裂缝带高度理论预计结果为40.25m,数值模拟结果为36.87m,而现场实测结果为38.50m.结果表明系统测量结果准确,观测过程高效.顶板导水裂缝带多段封堵同步测漏系统的研制和应用,不仅成倍减少工作量,而且实现连续精准测量,丰富了导高现场观测手段,对预防矿井突水灾害具有重要的实用价值.  相似文献   

6.
为解决进行水下开采时,采空区上覆岩层导水裂缝带的发育高度直接影响煤矿安全生产问题。针对大平煤矿覆岩类型和开采条件,参照N1S1单一开采试采工作面煤层的赋存条件和导水裂缝带高度的观测结果,应用岩石破裂过程分析RFPA2D系统,数值模拟得出了采放高度对导水裂缝带高度的影响程度,为大平煤矿单一综放开采预计导水裂缝带高度以及提高开采上限,提供重要的参考依据。  相似文献   

7.
大采空区覆岩破坏高度测控试验分析   总被引:3,自引:0,他引:3  
确定采空区上覆岩层破坏高度,对"三下"煤层安全、高效开采具有重要意义。利用彩色钻孔电视系统对覆岩破坏高度、现场钻孔冲洗液漏失量和钻孔水位变化等进行观测与分析,摸清煤层开采后大采空区上覆岩层内垮落带和导水裂缝带的发育高度及其分布形态和特点。这对安全、高效开采和大采空区围岩稳定性有效控制和定量化预测预报提供依据。  相似文献   

8.
为确定平顶山十矿近距离上行开采条件下覆岩垮落带及导水裂隙带高度.运用相似模拟、数值计算、理论分析以及现场钻孔窥视等诸多方法进行综合对比分析.结果表明:综合确定的导水裂隙带发育高度为28.8~32.7 m,与实测值误差为4.14%~8.28%,理论计算应选取大采深无渗流场计算公式;相似模拟—数值计算—大采深无渗流场公式计算的综合方法针对平顶山矿区预计导水裂隙带高度的准确性较好.建议在下一步深部开采中使用该方法估算导水裂隙带高度,研究结果对具有类似条件的矿井导水裂隙带预测具有一定借鉴意义.  相似文献   

9.
大采空区覆岩破坏高度测控试验分析   总被引:1,自引:0,他引:1  
确定采空区上覆岩层破坏高度,对“三下”煤层安全、高效开采具有重要意义。利用彩色钻孔电视系统对覆岩破坏高度、现场钻孔冲洗液漏失量和钻孔水位变化等进行观测与分析,摸清煤层开采后大采空区上覆岩层内垮落带和导水裂缝带的发育高度及其分布形态和特点。这对安全、高效开采和大采空区围岩稳定性有效控制和定量化预测预报提供依据。  相似文献   

10.
灵新煤矿西天河下安全开采技术综合分析   总被引:2,自引:1,他引:2  
为了研究灵新煤矿河下开采引起的覆岩破坏规律和地表移动规律,采用工程地质调查、彩色钻孔孔电视、钻孔冲洗液漏失量法、物理与数值模拟、地应力测量及地表监测等多种研究手段,获得了矿区地应力分布规律、工作面开采的垮落带和导水裂缝带的高度、岩层移动规律及矿压显现规律,实现了L3414综采工作面安全开采和环境保护的双重目标.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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