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建立了在特殊场地条件下,利用雷达探测仪对非开挖钻孔轨迹跟踪和控制的数学模型。在工程实践中,结合计算机技术,利用这个数学模型提供的方法,可以更有效地对非开挖导向钻孔轨迹进行跟踪和控制。 相似文献
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钻孔在地下空间的位置与形态，是根据地质、工程的要求进行设计的，其钻孔轴线，一般设计成空间直线型的垂直或倾斜孔，也有设计成空间曲线型的定向孔。无论何种线型，它们在地下空间都有一定的线型轨迹。在钻探施工中，由于地质和工艺等因素，其实际钻孔轴线，往往不同程度地偏离原设计钻孔轴线的轨迹，各个孔段出现顶角增大或减小和方位角增大或减小的现状，从而改变了原设计的轨迹和形态，这种现象就叫钻孔弯曲。运用不同的测量方法和测量仪器，测定出实际施工钻孔轴线在地下的空间座标位置，确定其空间形态。这一实践过程就是钻孔弯曲测量，简称测 相似文献
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给出了钻孔灌注桩水下砼灌注所采用的数学模型，根据此数学模型计算了初灌量，并把后续灌注分为５个阶段，对５个阶段的有关多数进行了近似计算。将计算值与工程实例进行了对比，基本吻合。 相似文献
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随着经济发展及矿产资源开发利用程度进一步提高,地质勘探向着深部、复杂地层发展,钻探施工钻孔也向着定向孔、分支孔的方向发展。地质目的对钻探工艺的要求越来越高,在控制钻孔轨迹方面也需越来越精准。本文就钻孔轨迹参数计算及成图作了详细介绍,阐述了钻孔轨迹相关概念及有关参数的计算方法;通过对Excel电子表格相关功能的研究,成功地将其应用到钻孔轨迹参数计算与处理分析中;通过对Solidworks三维制图软件的研究,成功地将其应用到钻孔轨迹监测及成图方面;通过实际工作案例验证了上述方法的可行性。 相似文献
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煤矿井下钻孔施工中,在缺少控制钻孔轨迹偏移测量技术的情况下,施工钻孔轨迹与钻孔设计轨迹偏差较大,无法满足煤矿瓦斯抽采的设计需求。阐述了随钻钻孔三维轨迹测量技术,目的是通过对随钻三维轨迹测量技术的研究,精确控制瓦斯钻孔轨迹,解决瓦斯突出煤层快速掘进及安全高效回采问题。钻孔随钻三维轨迹测量技术是通过对钻机开孔角度和钻孔轨迹的精确测量,使用三维轨迹成图方法显示。通过大量的数据采集与施工验证证明,该方法成为预抽钻孔煤层保安全、促生产过程中的重要环节,避免了钻孔设计及施工的盲目性,提高了抽采钻孔的利用率及施工速度。 相似文献
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定向钻孔施工阶段中，我们常会遇到当钻孔离靶点还有相当长的距离时，实际孔轴轨迹就已偏离了设计轨迹。怎样计算这一偏离造成的影响；怎样预测可能穿靶点；怎样选用合理的人工弯曲措施调整钻孔轨迹等等，均属控制计算问题。本文试图采用解析几何的方法，建立起靶区平面方程、直线孔段方程和圆弧孔段方程，然后求解它们的几何关系，如：钻孔与靶区的交点、实际轨迹与设计轨迹之间的夹角、可能穿靶点与设计靶点的距离等等。这样，可望提高定向孔施工中控制计算的精度和方便性。以利正确、有效地指导施工。 相似文献
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研究了地质钻孔信息的管理和可视化技术,提出了一种在数字地球平台中进行城市钻孔信息模拟和可视化的方法。该方法基于一个统一的钻孔数据库标准,首先将钻探点位信息和地层分层信息组织成具有不同细节层次的钻探点位模型、钻孔分层散点模型和钻孔管段模型,然后构建基于细节层次模型的海量钻孔信息多尺度表达机制,最后将这些模型加载到数字地球平台中进行可视化及查询、分析。在上海市的应用实例显示,该方法实现过程简单、自动性高,生成的模型易于在国际互联网上进行分发、集成与共享。该方法的应用将有助于地质工作者向其他科技人员以及社会公众展示、分发自己拥有的钻孔信息,为以钻孔数据为代表的城市地质信息的社会化服务奠定基础。 相似文献
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三维地质建模中虚拟钻孔的引入及其确定 总被引：1，自引：0，他引：1
三维地质建模中由于地质数据缺乏导致模型难以控制三维形体边界特征,直接影响到模型的实用价值.针对这一问题,文章引入了虚拟钻孔,用于增加数据点密度,有效控制三维形体边界.以地层受断层破坏为例,分别就地层与断层4种典型空间分布组合特征下虚拟钻孔的确定方法进行了研究,提出了相应解决方案.由于虚拟钻孔具有普通钻孔的性质,在数据存储方式、数据结构和表达方式等方面具有一致性,可以加快三维地质建模,提高建模精度. 相似文献
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为解决塔山煤矿高强度开采条件下瓦斯低含量、高涌出的问题,同时为了弥补大型物理实验和现场试验成本高、操作难的缺点,根据该矿8101工作面所属区域煤层的地质和瓦斯赋存条件,确定了数值试验方案,对地面垂直钻孔预抽特厚煤层瓦斯的效果进行优化分析。基于煤岩（体）的孔隙特征,构建了含瓦斯煤岩（体）破裂过程气-固耦合和渗透率-损伤耦合数学本构模型。采用RFPA2D瓦斯分析版软件建立地面钻孔抽放瓦斯的数值计算模型,设置有关简化条件、边界条件和物性参数,通过数值试验得出：地面垂直钻孔的终孔位置布置在煤层底部比较合理;在综合考虑地面垂直钻孔投入成本和瓦斯抽采效果的基础上,确定地面垂直钻孔间距为50～60 m比较合理。同时,由8101工作面地面垂直钻孔抽采煤层瓦斯的实际应用效果分析可知,当地面垂直钻孔的终孔位置布置在煤层底部,且钻孔间距布置为50 m时,能够实现良好的瓦斯抽放效果,这也从一定程度上进一步验证了数值试验的合理性和可行性。 相似文献
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In an exploration project, the placement of additional boreholes is based on the available information and engineering judgment, which may result in a lack of information or redundant information in decision making. This paper presents the use of dynamic multistage sampling to design directional and vertical boreholes to scan the subsurface. For this purpose, the potential collars of boreholes are determined within the survey area, while the imaginary boreholes in the form of cone sides cover the area's lateral surface area, and the concentric cones around the collars change with azimuth and dip angles. The objective function is a criterion used to determine the optimal borehole(s) and update the input borehole database in each stage; this iterative process continues until a stopping condition is satisfied. The presented algorithm was executed and validated on both synthetic and field data from the Eastern Kahang region in Iran. In the synthetic case, five additional boreholes were designated based on high grade and estimation error objectives that intersect two parts of the ore body. Ten proposed additional boreholes in the northeast region of Kahang coincided with the high grade copper mineralization zone. 相似文献
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Vertical electrical sounding was used for assessing the suitability of the drill sites in crystalline areas within a water supply project in Nampula Province in Mozambique. Many boreholes have insufficient yield (<600 L/h). Electrical resistivity tomography (ERT) was carried out over seven boreholes with sufficient yield, and five boreholes with insufficient yield, in Rapale District, in an attempt to understand the reason for the failed boreholes. Two significant hydrogeological units were identified: the altered zone (19–220 ohm-m) with disintegrated rock fragments characterized by intermediate porosity and permeability, and the fractured zone (>420 ohm-m) with low porosity and high permeability. In addition to this, there is unfractured nonpermeable intact rock with resistivity of thousands of ohm-m. The unsuccessful boreholes were drilled over a highly resistive zone corresponding to fresh crystalline rock and a narrow altered layer with lower resistivity. Successful boreholes were drilled in places where the upper layers with lower resistivity correspond to a well-developed altered layer or a well-fractured basement. There are a few exceptions with boreholes drilled in seemingly favourable locations but they were nevertheless unsuccessful boreholes for unknown reasons. Furthermore, there were boreholes drilled into very resistive zones that produced successful water wells, which may be due to narrow permeable fracture zones that are not resolved by ERT. Community involvement is proposed, in choosing between alternative borehole locations based on information acquired with a scientifically based approach, including conceptual geological models and ERT. This approach could probably lower the borehole failure rate. 相似文献
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多元统计分析在矿井断层预测中的应用 总被引：1，自引：0，他引：1
矿井小构造预测是一个难度极大的研究课题,根据岩层厚度、岩层组合关系,运用判别分析、地质统计学等数学方法预测矿井小构造,是一种全新的思想方法。本次研究选取我国西部某一煤矿作为研究对象,研究主采煤层上下岩性变化特征,根据岩石的不同抗压强度,确定五个变量;将已采区的钻孔分为含有断层的钻孔和不含有断层的钻孔,统计这两类钻孔中五个变量的值,建立判别函数,对未采区的钻孔进行判别分类。对每个钻孔的岩层在可采煤层的上下划分成10个层段,判别出每个层段中未知钻孔的归属,从而得到钻孔属于有断层的概率,即断层分布的概率等值线图。经实例验证,精确度达70%以上,对生产矿井具有一定经济效益和实用价值。 相似文献
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Boreholes drilled in the crystalline rocks of Nigeria have a reputation of failures and low yields. The performance of 256 boreholes drilled in different parts of the crystalline rocks of SW Nigeria were reviewed to determine their failure characteristics. 100% success was claimed for 105 boreholes constructed by one driller. Out of 111 other borehole records supplied by three other drillers 35 were abortive, representing a failure rate of 32%. In contrast, 24 owners of 40 boreholes reported 24 failures representing a failure rate of 60%.The common causes of borehole failure in the crystalline rocks of SW Nigeria are seasonal variations in water level, improper casing of the overburden, damage to pumps and other system failures such as blocked pipelines and malfunctioning tanks. Non-penetration into the water bearing horizon also features as a cause of borehole failure in this study.It is suggested that proper construction, operation and maintenance of boreholes will reduce the incidence of borehole failures in crystalline rocks of SW Nigeria. 相似文献
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底板岩巷穿层钻孔抽采技术和本煤层定向长钻孔抽采技术是目前高瓦斯和突出矿井回采工作面最为主要的瓦斯治理措施。晋城矿区赵庄矿煤层具松软低透气性特点,主要采用岩巷穿层钻孔消突为主,本煤层顺层钻孔消突为辅的瓦斯治理方法。但底板岩巷穿层钻孔存在工程量大、施工周期长及成本高等缺点,本煤层钻孔存在钻孔抽采不均匀、钻孔覆盖密度不足等技术缺陷。为对比考察底板梳状长钻孔与底板岩巷穿层钻孔的抽采效果,在赵庄矿1307采面开展了2种瓦斯治理方法。结果表明:抽采条件和抽采范围相同条件下,5个底板梳状长钻孔的瓦斯抽采总量占到底板岩巷穿层钻孔瓦斯抽采总量的75.4%,而底板梳状长钻孔的经济投入仅占底板岩巷穿层钻孔经济投入的29.2%。由此得出,研究区梳状长钻孔替代穿层钻孔的瓦斯抽采技术是可行的。该研究为底板梳状长钻孔替代底板岩巷的技术可行性提供了实践参考,为松软低透的高瓦斯和突出矿井的瓦斯治理提供了更为经济可行的治理方案。 相似文献
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Equipment has been developed for straddle packer testing in fractured-rock boreholes to conduct four types of tests (constant-head step tests, slug tests, constant-rate pumping tests, and recovery tests) without deflating the packers or adjusting equipment in the hole between tests. The goal is to achieve improved accuracy and precision in the determination of transmissivity (T). Water-pressure measurements are recorded using pressure transducers positioned above and below the test interval to identify connections from the test interval to the open borehole. Insights concerning the nature of test conditions are gathered with this equipment to assess errors related to deviations from assumptions inherent in the mathematical models used to determine T, including validation of the Darcian flow assumption, validation of slug test assumptions, cross-connection to the open borehole, inadequate borehole development, and dual permeability, thereby giving greater confidence in the calculated T values. When the errors indicated above are minimized, the constant-head step tests, slug tests and constant-rate pumping/recovery tests give nearly identical values. This multiple-test approach to fractured-rock studies increases confidence in test results, which is important when the goal is characterization of fracture networks for contaminant transport and fate assessment. 相似文献