潜孔锤偏心跟管钻进法在卵砾石地层岩土工程勘察中的应用

卵砾石地层是钻探工程中常见的一种典型的难钻进不稳定地层。通过采用潜孔锤偏心跟管钻进法,从根本上解决了卵砾石地层难以钻进的难题,结合都匀市区岩土工程勘察实例,笔者认为潜孔锤偏心跟管钻进法是在卵砾石地层钻进中行之有效的一种钻进法。     

水源井同径套、筛管封井止水工艺

水源供水井，在封井止水下艺中，始终存在封井质量、水泥固结质量及井内钻具事故等风险，为此在对准格尔旗施工的10口水源供水井施工中，制作了单向逆止阀水泥封隔器，并与Ф340套、筛管用吊卡按一定顺序下入井内。该装置的使用，有效地提高了封井止水的质量。     

Dynamic response of partially sealed circular tunnel in viscoelastic saturated soil

Based on Biot's wave equation, dynamic response of a circular tunnel with partially sealed liner in viscoelastic saturated soil is investigated. By introducing two scalar potential functions, the analytical solutions of stresses, displacements and pore pressure induced by axisymmetric gradually applied step load are derived in Laplace transform domain. Numerical results are obtained by inverting Laplace transform presented by Durbin and used to analyze the influences of partial permeable property of boundary and viscoelastic damping coefficient of soil on dynamic response of the tunnel. It is shown that the attenuation of radial displacement appeared with the increase of viscoelastic damping coefficient of soil, and relative rigidity of liner and soil, and the influence of partial sealing property of boundary on stresses, displacements and pore pressure is remarkable. The available solutions of permeable and impermeable boundary conditions are only two extreme cases of this paper.     

地质钻探中的井漏及堵漏材料研究

通过对钻探过程中井漏的复杂地质因素分析,提出了水化膨胀复合材料体系,并对该体系进行了膨胀性、封堵性及复合桥接堵漏模拟实验.实验结果表明,堵漏材料PAR具有很强的吸水膨胀性能,可膨胀至原体积的几十倍,且时间快有利于形成快速的封堵.材料PAR与稻谷和锯末形成的复合堵漏材料具有很强的堵塞率,可达70%以上.承压堵漏测量装置中测试表明:复合堵漏体系不仅能形成封堵,而且能够承受一定的压差.在云南临仓市勐简乡铅锌矿钻探过程中,运用复合堵漏体系满足了该地区复杂地矿钻探需要.     

新疆白干湖钨锡矿区岩心钻探施工技术

随着西部大开发及国家三五八工程的开展,新疆昆仑山脉高海拔无人区成为地质找矿的重点,如何提高昆仑山脉钻孔钻探施工的效率,是当前岩心钻探施工的重点。通过白干湖钨锡矿岩心钻探的施工情况论述了该工程的施工经验和方法。     

Study on deepwater conductor jet excavation mechanism in cohesive soil

Conductor casing jetting technique has been increasingly applied in deepwater drilling. The insight into the jetting excavation mechanisms is critical in guiding a successful conductor casing jetting operation. The real- time continuous jet excavation process is simulated with the volume of fluid (VOF) multiphase method of CFD (Computational Fluid Dynamics) ANSYS Fluent calculation software in the current study. The cohesive soil is modelled by using a kind of viscous fluid with Herschel-Bulkley model. In addition, a laboratory half round nozzle jet excavation test is designed for verification by comparison of the observed jet excavation profile with the numerical results. The sensitivity parameters affecting the conductor jetting excavation mechanism in cohesive soil are thus investigated. It is found that the application of Herschel-Bulkley (HB) model for cohesive soil and the VOF method of Fluent can provide a good simulation of jet excavation process. The maximum excavation depth can be determined by the undrained ultimate bearing capacity of the circular foundation with a bearing capacity factor of 6.7. The nozzle position, jet velocity and soil strength have significantly influence on the depth and width of the jet excavation profile in conductor oblique jet.     

鄂尔多斯盆地北部泊尔江海子断裂对上古生界天然气成藏的控制

为了揭示泊尔江海子断裂对鄂尔多斯盆地北部杭锦旗地区上古生界天然气成藏的控制作用,应用地震和钻井资料,在断裂活动性分析的基础上,根据断层泥比率和断层连通概率法对泊尔江海子断裂的侧向和垂向封闭性进行半定量评价,探讨断裂和天然气富集区的关系。结果表明：泊尔江海子断裂呈现3次明显的活动高峰期,分别为加里东期-早海西期的断裂形成期、印支期-早燕山期的挤压逆断裂活动期、中晚燕山期的走滑撕裂活动期,而中晚燕山期的走滑撕裂控制了上古生界天然气主要成藏期。断裂的封闭性具有“横向分段、纵向分层”的特点;横向上,以断层泥比率(SGR)等于0.3为界将泊尔江海子断裂分为侧向优势输导区和侧向封闭区;纵向上,在石千峰组和上石盒子组断裂启闭系数基本都小于1.0,断裂垂向封闭,在下石盒子组和山西组断裂启闭系数主要集中在4.0~10.0,断裂垂向开启。在断裂侧向优势输导区,断裂南部主力烃源区生成的天然气,经断裂发生垂向和侧向运移,易在断裂北部地区富集成藏;在侧向封闭区,则易在断裂南部地区富集成藏。     

深水压力舱密封技术研究

管道屈曲技术试验过程当中,发现深水压力舱的出厂自带密封工艺耗时过长、密封效果不好、安全性不佳、返工现象普遍.针对这一现象,采用全新的密封工艺流程与方法:在前期处理中对螺柱编号与清理以防止螺母安装过程中的卡死现象;采用自创的精度控制方法防止漏水以及返工;根据不同的工作压力对密封技术进行梯度划分,选取不同的密封方案.经过实...     

嫩江组二段底部标志层岩石矿物学特征与成片套损因素新认识

大庆油田嫩江组二段底部与嫩江组一段顶部成片套损严重，从前一直认为泥岩吸水膨胀、蠕变是导致成片套损的主要因素。成片套损位置研究发现，嫩江组二段底部与嫩江组一段顶部成片套损实际集中于嫩江组二段底部标志层内，而嫩江组二段底部标志层岩石矿物学特征综合研究结果表明，其不含遇水膨胀的蒙脱石，且粘土矿物含量也低于其上下相邻岩石，表明其遇水膨胀与蠕变较弱，岩石遇水膨胀与蠕变不会构成成片套损的主要原因。嫩江组二段底部标志层岩石岩心观察描述、镜下鉴定、矿物成分综合测试和岩石强度性质研究发现，嫩江组二段底部标志层泥岩为富含长英质的质地坚硬岩石，含粘土矿物较少，不含蒙脱石，岩石吸水能力差、膨胀与蠕变能力弱；标志层中存在多个化石富集带，化石沿岩石层理分布形成沿层理方向的区域性力学薄弱面；沿化石层层理的抗张强度与抗剪强度远低于其他层位和垂直于层理方向的强度性质。因此，一旦注入水进入嫩江组二段底部标志层，富含化石的岩石沿岩石层理优先发生破坏，并迅速扩展，形成成片套损现象。     

Topographic zonation of infiltration in the hilly loess region,north china

Field infiltration tests using portable rainfall infiltrometers were conducted in the Wangjiagou experimental basin in the hilly loess region of north China. Based on data collected at 27 sites, a topographic zonation of infiltration characteristics was observed. The average steady infiltration rate and the average ponding time decreased from the hilltop to the hillslope and further decreased to the gully wall. Such a zonation is closely related to the variations of topography, soil and land use conditions in the study area. A general infiltration model is proposed. Collected field data are used to establish the applicability of the proposed model in the study area.