旋挖钻进中硬岩及卵砾层钻头结构及施工工艺研究

旋挖钻进技术作为一种高效优质的钻进方法近年来广泛地被用于公路、铁路及大型水电站基础工程施工建设中，取得了良好的社会效益和经济效益。探讨了在卵砾石、漂石等复杂地层以及坚硬基岩中进行旋挖钻进所用钻头的结构及其施工工艺。     

岩土钻掘设备的液压步履机构

因液压步履移位最方便，辅助时间短，换向灵活，移位对孔准确，大型岩土钻掘设备施工的群孔现场实现近距离的自行迁移多采用液压步履机构。详细叙述了双向移动和单向移动加转向步履机构的结构和特点。     

新型充气钻井液在新疆严重漏失地层的应用

利用特殊植物纤维KWS作为泥浆处理剂的新型充气钻井液，不仅具有常规充气钻井液低密度、排粉能力强、节约用水等优点，还可以不受钠、钙离子的影响，提高钻井泡沫稳定性和钻井液抗盐能力。通过采用此种新型充气钻井液，利用其低密度特性、特殊泥饼、泡沫的群体封堵作用和泡沫的疏水屏蔽作用，成功解决了裂隙地层的漏失问题，恢复了钻探生产。在我国西部干旱缺水漏失地区具有良好的应用前景。     

液体高膨胀材料充填堵漏试验应用

介绍了钻探施工中，利用膨胀材料充填、堵漏的新工艺，其具有经济、高效、安全的特点。     

Numerical simulation of percussive drilling

This paper presents a novel dynamical model to analyze the long‐term response of a percussive drilling system. This departs from existing approaches that usually consider a single activation and bit/rock interaction cycle for the analysis of the process performance. The proposed model integrates the axial dynamics of an elastic piston and an elastic drill bit, a motion‐dependent pressure law to drive the piston, and a generalized bit/rock interaction law representative of the dynamic indentation taking place at the bit/rock interface. It applies to down‐the‐hole percussive drilling as well as top‐hole, with minor modifications. The model does not account for the angular motion or the hole cleaning, however. The model is first formulated mathematically; then, a finite‐dimensional approximation is proposed for computations. Numerical analyses of the model response, for a low‐size down‐the‐hole percussive system, follow. The period‐1 stationary response for the reference configuration is studied in detail, and parametric analyses assessing the influence on the rate of penetration of the bit/rock interaction parameters, the feed force, and the percussive activation parameters are conducted. These analyses reveal that the multiscale nature of the process is well captured by the model and recover expected trends for the influence of the parameters. They also suggest that a significant increase of the penetration rate can be achieved by increasing the percussive frequency. Copyright © 2015 John Wiley & Sons, Ltd.     

EXPLORATION ENGINEERING

正20141864 Deng Mengchun(Institute of Exploration Technology,CAGS,Chengdu 611734,China);Huang Shenghui Rock Sample Collection and Division Technologies for Air Reverse Circulation Sampling Drilling(Exploration Engineering,ISSN1672-7428,CN11-5063/TD,40(7),2013,p.73-76,80,16 illus.,5 refs.)     

Diagnosing snow accumulation errors in a rain‐snow transitional environment with snow board observations

Diagnosing the source of errors in snow models requires intensive observations, a flexible model framework to test competing hypotheses, and a methodology to systematically test the dominant snow processes. We present a novel process‐based approach to diagnose model errors through an example that focuses on snow accumulation processes (precipitation partitioning, new snow density, and snow compaction). Twelve years of meteorological and snow board measurements were used to identify the main source of model error on each snow accumulation day. Results show that modeled values of new snow density were outside observational uncertainties in 52% of days available for evaluation, while precipitation partitioning and compaction were in error 45% and 16% of the time, respectively. Precipitation partitioning errors mattered more for total winter accumulation during the anomalously warm winter of 2014–2015, when a higher fraction of precipitation fell within the temperature range where partition methods had the largest error. These results demonstrate how isolating individual model processes can identify the primary source(s) of model error, which helps prioritize future research.     

HYDROGEOLOGY & ENGINEERING GEOLOGY

正1.HYDROGEOLOGY20142452Chang Chengcao(Institute of Coalfield Geological Survey and Design of Jilin Province,Changchun 130062,China)Hydrogeological Type Division of Coal Mine No.2Mine in Yitong Manchu Autonomous County,Jilin Province(Jilin Geology,ISSN1001-2427,CN22-1099/P,32(4),2013,p.129-131,3refs.)     

松辽盆地大陆科钻二开段大井眼钻井液技术

CCSD-SK2井是一口钻穿松辽盆地白垩纪陆相沉积地层的中国大陆科学钻探井。二开段先以216mm口径钻至2806.20m,然后进行444.5mm口径扩孔。泥页岩地层大井眼钻进过程中粘土矿物含量高且易造浆,砂砾岩层渗透性强易粘卡,井壁稳定控制与钻屑携带难度大。选用了钾铵聚合物钻井液体系和聚磺钻井液体系,通过正交实验确定了钻井液配方。将钻井液控制在合适的密度、较低的失水量以及较强的封堵性,有效实现了井壁稳定;保持适当的环空返速、较高的动塑比以及定期打稠塞举砂等措施,有效实现了井眼净化。1086.45m~1147.56m与1182.74m~1256.01m井段累计收获岩心130.90m,取心率达到97.41%,平均机械钻速为0.84m/h;最终顺利钻至2806.20m。     

利用压密方程计算分析西安市地面沉降特征

利用西安市地下水位监测资料,基于水文地质三维结构模型,在不考虑粘土层滞后压缩变形的理想情况下,采用压密方程计算获得西安市抽取地下水可引起的理论地面沉降量及沉降分布特征,结果表明:计算所得沉降显著区位于西安市西南部的高新区及东南部的曲江新区,沉降量呈由北向南递增的特征,与InSAR监测结果整体趋势具有较好的一致性;地面沉降分布特征受到活动地裂缝影响,沉降曲线呈近NE向偏转展布。研究结果可为沉降灾害预防研究提供宏观的参考信息。