【作者】 楼日新；

【导师】 黄润秋；

【作者基本信息】 成都理工大学 ， 地质工程， 2007， 博士

【摘要】 复杂地层的钻进与取样问题一直是地矿勘探、工程勘察、岩土工程施工中的一个技术难题。由于复杂地层结构松散、无规律包裹砂卵砾石、砾石大小不均、换层频繁、软硬悬殊、颗粒级配悬殊等，存在钻进、保护孔壁、取心这三大难题，常规的钻探技术难以满足施工要求。复杂地层钻探技术先后经历了锤击跟管取芯钻进和金刚石取芯钻进两个重要阶段。现有的砂卵石层SM胶金刚石钻进取样技术解决了一些稍复杂地层的钻进与取样问题，但至今，仍无法适应较复杂的地层，钻孔质量和钻进效率仍处于低水平状态。论文主要从复杂地层钻探的适应性、钻进方式、钻进冲洗介质、钻进取心工具等方面开展研究工作，对于不同类型的复杂地层，提出了相适应的钻进与取样新技术、新方法。通过研究取得了以下主要成果和结论：（1）采用应力波理论，分析了潜孔锤跟管钻进碎岩过程及影响因素。对潜孔锤跟管钻进过程中的跟管钻压、套管自重、潜孔锤冲击功、跟管钻进速度、跟管深度、扩孔口径和钻进中的钻压值进行了理论推导，得出：①潜孔锤跟管钻进速度取决于潜孔锤的冲击功、岩石的单位体积破碎功和凿岩直径三个因素；②在简单和复杂工况条件下的最大跟管深度l₀、l_max的计算公式，包括下向垂直孔和水平孔时的最大跟管深度的计算公式；③分析了跟管钻进钻压与机械钻速的相互关系，提出了跟管钻进的钻压以每厘米钻头直径0.5～0.9kN为宜。（2）国内外现有的空气潜孔锤跟管钻进技术主要应用于比较松散、均质、架空不严重及中等可钻性地层，均属全断面跟管钻进，效率虽高，但不能取芯。本文将空气潜孔锤跟管钻进技术和岩芯钻探技术结合，利用前者钻进速度快和护壁效果好、后者具备采集岩芯能力的技术优势，开发了新型的钻进与取样技术方法——空气潜孔锤取芯跟管钻进技术。该技术的主要特点有：①钻具结构采取同步、同心跟管钻进原理；采用中心钻头（唇面）超前套管钻头的阶梯钻进原理；采用双层管和三层管两种结构方法，可以满足的取芯要求；②钻具采用的外管和岩心管均为地质钻探以及石油钻井的标准管材系列，市场货源充足，互换性好；③空气潜孔锤取芯跟管钻进可以取得能够客观反映地层情况（层位、包裹情况等特性）岩心；④发挥潜孔锤钻进效率高的技术优势，采取取芯和跟管一次完成，钻进效率可以大幅度提高；此外，进行了取芯钻头和套管钻头的研制；研究制订了实用、操作性强的空气潜孔锤取芯跟管钻进技术规程。该技术配套采用当前国内地质勘察单位常用的空压机、冲击器、钻杆等，具有通用性和适应性。该技术适合于50m以内浅部复杂地层，特别是Ⅱ类复杂地层钻探取芯。（3）在原有的GJ型扩孔张敛式跟管钻具的基础上，研究开发了冲击式金刚石取芯跟管钻进技术。该技术特点为：①组合张敛式扩孔钻头对称分布并呈锥形；②钻具承压和承扭能力足以满足常规钻进要求；③两级钻头的同轴度好，导向和扶正相辅相成，不会造成钻孔弯曲；④泄漏通道的设置在满足扩孔钻头冷却和冲刷要求的同时，不会造成孔底钻头缺少必要的冷却液体；⑤在悬挂腔设计了调节圈，通过加减调节圈确保悬挂机构承受钻具重力，消除了收敛爪异常受力情况；⑥设计了排沙系统，避免颗粒物质滞留钻具内部，确保钻具张敛性能的可靠性。冲击式金刚石取芯跟管钻进方法适合在复杂地层钻探。该方法可减少孔内事故，降低材料消耗，提高钻进效率和钻探工程质量；简化钻孔结构；可为处理孔内事故提供条件。（4）国内外现有的气动潜孔锤跟管钻进技术存在四个方面的问题：第一，钻具的规格、系列不完善；第二，钻具设计不完善；第三，钻具的制造技术如材料选择、热处理工艺不能满足要求；第四，设备配套、施工操作规程亟待提高。小湾电站锚固和支护工程地形陡峻、地层情况较为复杂。锚固施工成孔困难的地层主要有崩塌堆积体和受构造、风化卸荷作用影响而破碎的基岩。针对小湾水电站的这一地层特点和原有技术存在的问题，设计开发出了二种类型的气动潜孔锤偏心跟管钻具。这两种偏心跟管钻具的特点有：①依靠中心钻头和偏心扩孔钻头实现二级破岩、设计合理的排渣系统使排渣顺畅以及与具有足够冲击功的冲击器相适配等；②具有中心钻头起导向作用的偏心跟管钻具结构对于地层复杂的小湾电站更有利于孔斜的预防，从而更大限度地满足工程设计的要求；③钻具在结构上设计用键来传递扭矩，加之选用了高强度的材料，采用了特殊的热处理工艺，合理的固齿工艺，确保了钻具寿命；④联接销系统为相互自锁的结构，保证了中心钻头与导正器之间连接具有良好的可靠性，解除了掉钻之忧。同时，针对工程特点提出了钻机、空压机、潜孔锤合理选择原则和配套型号；对钻机进行了合理的改进；编制出了具有施工指导意义的潜孔锤跟管钻进工艺规范。（5）套管的起拔速度直接影响着锚索的施工效率。针对工程实际，研制了起拔力为650KN的系列液压拔套管设备，其主要技术特点有：①系列液压拔管机结构简单，体积小、重量轻，装拆、操作方便；②操作台与液压泵站分开设置，适合于搬运、迁移困难的边坡工程使用；③充分考虑了在陡坡上套管起拔的实际问题，底座和油缸采用铰接；④一台设备可起拔多种规格的套管，形成系列。（6）潜孔锤跟管钻进技术在二郎山龙胆溪滑坡整治堆积体工程、黄金坪电站坝基覆盖层钻进成孔与灌浆试验工程、雅砻江官地水电站左岸边坡锚索工程等近十个工程的复杂地层钻进成孔和取样中应用了研制的偏心跟管钻具、液压拔管机和工艺操作规程，取得了好的钻进成孔效率和取样质量。在一定程度上解决了深厚覆盖层、卵石层、堆积体成孔与取样技术难题，有创新性。更多还原

【Abstract】 The drilling and coring for complex stratum has always been the main and difficult problem in the geological and mining exploration, the engineering of exploration, and the geotechnical engineering. Since the complex formation of sedimentary layers generally contain clay, flow sand, egg stones, gravel, big stones, it posed difficulties and problems to the drilling, hole-wall-protecting, and coring of the stratum, which can not be simply solved by any usual drilling technology. The hydraulic and hydroelectric engineering at home has undergone two phases, the down-the-hole hammer core-drilling with casing and the diamond core drilling （the two significant breakthroughs in technology）. In particular, the development and broad application of SM-gel diamond core drilling for the gravel layer has fundamentally transformed the drilling technology in this field, for it has solved to a certain degree some of the drilling and coring problems. However, till now, the SM gel diamond core drilling can not be applied to the complex stratum. As a result, the quality and efficiency of drilling remain at a very low level.Through the analysis and research on the drilling applicability into the complex stratum, the drilling techniques, the drilling fluid, the coring tools, etc., this paper has proposed the correspondingly new drilling methods and technology for different stratum, aiming to promote the drilling technology as such. Therefore, some major findings and conclusions are made as follows:（1） Heavily drawing on the stress wave theory, the paper describes and illustrates the down-the-hole hammer drilling process, analyzing especially the drilling process of rock-breaking with DTH hammer and the relative factors. With the eccentric drilling as the case in study, the paper has also generated a theoretical model for the analysis of pipe drilling pressure, case weight, percussive capacity, pipe drilling speed and depth, reaming gauge, the value of pipe drilling pressure in the process, and made the following findings:①the pipe drilling speed is determined by the percussive power of DTH hammer, rock-breaking power per volume, and the diameter of aperture; ②in terms of different drilling conditions, the paper has proposed, respectively for simple operating mode and complicated operating mode, the formula to calculate the maximum casing depth, namely l₀ and l_max, of both vertical and horizontal holes;③based on the analysis of the relation between pipe drilling pressure and drilling speed, the paper has concluded that the most appropriate pipe drilling pressure is 0.5～0.9kN per centimeter of the casing bit diameter.（2） The pipe drilling with air-powered DTH hammer is with limitation applied to the shallow, loose and even-grained formation with few aerial strata, which is of medium drilling characters. Though with high efficiency, it is simply a full-section drilling with casing, and not capable of coring. With the integration of air-powered DTH hammer drilling and core drilling, this research has developed a new drilling and coring method—the technology of air-powered DTH hammer and core drilling with casing, by combining the high drilling speed and efficient hole-wall protection of the former with the core gathering capacity of the latter. The drilling equipment is mainly characterized by the following features:①the drill tool is structured in the way of drilling with simultaneous and concentric case; the equipment follows the mechanism of stage drilling and employs the pre-casing bit in the form of centre bit （profile）; to meet the requirements of coring in either gravel or loose strata, the drilling tool is in double-piped making and tri-piped making, respectively;②the outer and core barrels are in rich supply and available in market, since they are general equipment for geological and oil drilling;③the core extracted by air-powered DTH hammer and core drilling can illustrate the factual state and characteristics of the formation （its position, its composition, etc.）;④owing to the use of highly-efficient DTH hammer drilling, coring and casing are completed simultaneously to achieve the high drilling efficiency;Besides, the coring bit in pipe drilling and casing bit have also been developed in the research; and practical and feasible regulations have been made for the air-powered DTH hammer and core drilling with casing. As general apparatus for geological exploration at home, such as air compressor, percussion tool, drill, the drilling equipment employed in the technology are easily available. Moreover, this technology is better applied to the drilling into shallow complex formation within 50m, especially to the core drilling into the II type complex stratum.（3） Based on pipe drilling with GJ reamer, the research has innovated the technology of percussive diamond core drilling with casing, which has the following characteristics:①the expansive-contracted reamer is cone-like and symmetrically structured; ②the drilling apparatus are able to meet the demand of conventional drilling on the bearing of pressure and twist;③the drilling bit and coring bit, in concentric pattern, are combined to function well in both orientation and adjustment in direction, and can avoid the hole deviation;④the design of drainage outlet contributes to the cooling and flushing of reamer without reducing the necessary cooling liquid at hole bottom.⑤the adjustable rings in the hanging cavity can not only help the contraction of reamer, but also guarantee the load-bearing capacity of hanging apparatus by increasing or decreasing the rings, so as to eliminate the abnormal stress on the claw.⑥the sand flushing system can prevent grainy stuff from sticking to the drilling tool, so as to guarantee the expansion and contraction of core bit.The technology of percussive diamond core drilling with casing has been well applied to the drilling into complex stratum to achieve remarkably positive effects in technology and economics. And this method can reduce the drilling accident and the consumption of drilling material so as to enhance the efficiency and quality of drilling; it also simplify the hole structure and makes it possible to solve the backfire accident.（4） At home and abroad, there still remain four problems in the technology of air-powered DTH hammer drilling with casing: first, the gauge of drilling tool is not uniformed and the series of drilling products are not complete; second, there are obvious defaults in the design of drilling tool; third, the manufacturing technique of drilling tool, such as the selection of raw material and the heat treatment process, can not live up to the requirement; four, the production of complete set of drilling equipment as well as the operating regulation for the equipment need improving urgently.Due to the characters of the complex stratum in Xiao Wan hydropower station, the high-slope anchoring and reinforcement projects in the high slope bank have encountered the drilling difficulty mainly in the collapsed formation deposits and the foundation bed broken under the impact of geological formation and aeolian erosion. To solve the technological problems in the complex formation, this research has innovated two types of air-powered DTH hammer drilling equipment, The two types of drilling equipment have the following properties:①the use of both centre bit and eccentric reaming bit forms the two-stage rock breaking; the design of slag flushing system ensures sufficient percussion impact of the percussive drilling tool;②the eccentric drilling with casing that employs the centre bit can better prevent the hole deviation;③the drilling equipment has high endurance, due to the design of key connection to deliver the torque, the selection of high strength material and the special heat treatment in manufacturing the drilling tool, as well as the proper techniques of fixing the gear tooth engagement;④the keys are interlocking devices that strongly and reliably attach the centre bit to the adjuster to avoid the risks of bit losing.At the same time, in accordance with the drilling characters in Xiao Wan, the selection of the drilling tool, the air compressor, and the DTH hammer has followed the principle of mutual adaptation and matching, and the innovation of drilling tool has also been made. Moreover, the operation specifications and regulations for DTH hammer drilling with casing have also been proposed.（5） Since the pulling speed has direct effects on the anchoring efficiency, the research has developed a series of hydraulic pull casing that has the pulling force of 65t. The technical features are as follows:①the series of pull casing are simple, small, and light, easy to be assembled, dissembled, and operated;②the separation of operating board from the hydraulic pump unit is better applicable to the high slope drilling projects suffering from difficult delivering and shifting;③for the sake of pull casing in high slope, the foundation of operating board and the petrol cylinder have been joined on hinges;④each device can pull out a series of casing pipes of different gauges.（6） The technology of DTH hammer drilling with casing has been successfully applied to the drilling and coring into the complex stratum in more than ten projects, such as the project of slope rectification and anchoring in the Sichuan-Tibet Highway at Longdan River of Mt. Erlang, the cover curtain grouting test of the foundation in Gold Ping Power Station, the project of pre-stressing anchoring for the cable platform on the slope of the left bank of the Guandi Power Station of Yalong River. The application of the innovated eccentric drilling tool with casing, the hydraulic pull casing device, and the operation specifics and regulations has been proved efficient in both drilling and coring. The new drilling technology has been able to solve the drilling problems to a certain extent in the complex stratum with deep covering, cobble and pebble layers, and formation deposits.更多还原