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221.
超级润滑聚合物泥浆在泰国北部Banthi构造定向井中的使用   总被引:1,自引:0,他引:1  
陈亮 《陕西地质》2004,22(1):63-67
“FA—BT—45—03/2”和“FA—BT—45—03/3”是中泰两国在泰国北部芳县盆地Banthi构造上合作施工的疋向井。在该地区使用超级润滑聚合物泥浆,不仅提高了钻速,而且解决了携砂、剥落掉块、漏失等复杂问题,提高了钻井效率。施工中采用油层保护技术,大大降低了油层污染,为采油提供了良好的条件。  相似文献   
222.
通过对矿井锚索支护巷道喷浆骨料的各种配比试验研究,结合现场的实际应用,总结出比较适合巷道喷浆使用的采用红矸石做骨料的骨料配比方案。  相似文献   
223.
Much of our understanding of submarine sediment‐laden density flows that transport very large volumes (ca 1 to 100 km3) of sediment into the deep ocean comes from careful analysis of their deposits. Direct monitoring of these destructive and relatively inaccessible and infrequent flows is problematic. In order to understand how submarine sediment‐laden density flows evolve in space and time, lateral changes within individual flow deposits need to be documented. The geometry of beds and lithofacies intervals can be used to test existing depositional models and to assess the validity of experimental and numerical modelling of submarine flow events. This study of the Miocene Marnoso Arenacea Formation (Italy) provides the most extensive correlation of individual turbidity current and submarine debris flow deposits yet achieved in any ancient sequence. One hundred and nine sections were logged through a ca 30 m thick interval of time‐equivalent strata, between the Contessa Mega Bed and an overlying ‘columbine’ marker bed. Correlations extend for 120 km along the axis of the foreland basin, in a direction parallel to flow, and for 30 km across the foredeep outcrop. As a result of post‐depositional thrust faulting and shortening, this represents an across‐flow distance of over 60 km at the time of deposition. The correlation of beds containing thick (> 40 cm) sandstone intervals are documented. Almost all thick beds extend across the entire outcrop area, most becoming thinly bedded (< 40 cm) in distal sections. Palaeocurrent directions for flow deposits are sub‐parallel and indicate confinement by the lateral margins of the elongate foredeep. Flows were able to traverse the basin in opposing directions, suggesting a basin plain with a very low gradient. Small fractional changes in stratal thickness define several depocentres on either side of the Verghereto (high) area. The extensive bed continuity and limited evidence for flow defection suggest that intrabasinal bathymetric relief was subtle, substantially less than the thickness of flows. Thick beds contain two distinct types of sandstone. Ungraded mud‐rich sandstone intervals record evidence of en masse (debrite) deposition. Graded mud‐poor sandstone intervals are inferred to result from progressive grain‐by‐grain (turbidite) deposition. Clast‐rich muddy sandstone intervals pinch‐out abruptly in downflow and crossflow directions, in a fashion consistent with en masse (debrite) deposition. The tapered shape of mud‐poor sandstone intervals is consistent with an origin through progressive grain‐by‐grain (turbidite) deposition. Most correlated beds comprise both turbidite and debrite sandstone intervals. Intrabed transitions from exclusive turbidite sandstone, to turbidite sandstone overlain by debrite sandstone, are common in the downflow and crossflow directions. This spatial arrangement suggests either: (i) bypass of an initial debris flow past proximal sections, (ii) localized input of debris flows away from available sections, or (iii) generation of debris flows by transformation of turbidity currents on the basin plain because of seafloor erosion and/or abrupt flow deceleration. A single submarine flow event can comprise multiple flow phases and deposit a bed with complex lateral changes between mud‐rich and mud‐poor sandstone.  相似文献   
224.
堵漏试验仪是制定防漏堵漏技术方案的关键实验设备之一。针对现有堵漏试验仪普遍存在的结构复杂、试验流程繁冗、浆液用量较大、数据重现性较差等问题,设计了一种中压(试验压力为0~1 MPa)堵漏试验仪。该装置能模拟1~3 mm的条缝型漏失地层和1~4 mm的孔洞型漏失地层,封板(缝板和孔板)的实际漏失面积为0.35~2.79 cm2,孔隙率1.81%~14.24%。基于该试验装置,获取了由膨胀堵漏剂、核桃壳等组成的适于不同漏失地层的堵漏浆液配方。研究发现,堵漏浆液的封堵效果不仅取决于裂缝或孔洞的大小,也要考虑其孔隙率。该堵漏仪及堵漏浆液配方可为钻井防漏堵漏工作提供有益参考。  相似文献   
225.
马艳超 《探矿工程》2017,44(6):58-61
龙凤山气田属于典型的裂缝性储层,钻井过程中漏失问题突出。该气田地层压力系数低、气层活跃、井壁稳定性差,固井难度较大。针对本区块特点,强化固井工艺措施,做好钻完井过程的防漏、承压堵漏工作,优选完井方法,采用变排量顶替工艺技术,开展低密度水泥浆体系优选研究,合理设计浆柱结构,有效地解决了固井过程中的漏失和候凝期间气窜等问题,保证了固井质量,实现了油层的有效封固,现场应用效果良好。  相似文献   
226.
Studying sedimentation and consolidation of dredged slurry has significant implications to the design of storage yard and subsequent ground improvement. In this study, settling velocity of soil particles in dredged slurry during sedimentation and consolidation processes was investigated using an improved multilayer extraction sampling (MES) method. A series of sedimentation column tests were performed on dredged slurry with three different initial water contents. Distributions of volume of soil particles and density of dredged slurry were first obtained by the MES method, settling velocity of soil particles was then calculated by volume flux function approach. It was found that the density and velocity inflection points can be used to distinguish the settling zone and the consolidation zone. The experimental results reveal that the velocity of soil particles was quite low and monotonically decreased with sedimentation height at low initial water content throughout the whole test period, whereas it was increased at 0–1 hours and almost remained constant at 1–7 hours in the settling zone at high initial water content. The effects of initial water content on sedimentation and consolidation mode of dredged slurry and the settling velocity of soil particles were discussed. The relationship between settling velocity of soil particles and particle diameter was also studied. It is indicated that the measured velocity of soil particles was much lower than that calculated by the Stokes equation, and it was related to 0.4881–0.5906 order of particle diameter at 0–1 hours and 0.1117–0.1825 order of particle diameter at 1–7 hours for the test slurries.  相似文献   
227.
耿哲  李树忱  赵世森  张靖宇 《岩土力学》2018,39(Z1):469-476
泥水平衡盾构开挖过程中常遇到盾构顶推力难以确定且波动复杂的问题。针对该问题,对盾构推进过程中所受阻力进行系统的分析,确定了阻力的组成部分和计算方法,改进了盾壳与周围土体间摩擦力的计算公式。分析泥水平衡盾构推进系统的组成和工作原理,基于盾构推力的静力学模型建立了单自由度动力学模型,根据能量守恒原理建立了系统的平衡微分方程,推导出盾构推力的非线性动力学公式。基于上述公式,分析了盾构推力的变化趋势和波动规律,确定了液压油缸的最佳行程距离。通过与武汉地铁8号线越江隧道长江穿越段盾构顶进推力的实测数据对比分析,验证了提出公式能够正确计算管片衬砌所受的动态顶推载荷,对衬砌结构内力分析具有重要意义。  相似文献   
228.
张林 《探矿工程》2014,41(6):80-84
盾构掘进施工过程中,由于开挖破坏了地层原始应力状态,地层产生应力增量,特别是剪应力增量,引起地层移动导致不同程度的地面沉降。超大直径泥水平衡盾构掘进施工参数控制不当极易造成地面沉降差异过大,影响地面建(构)筑物安全和使用。对南京纬三路过江通道N线大直径泥水平衡盾构穿堤掘进施工进行总结,为类似大直径泥水平衡盾构穿越地面建筑物施工提供借鉴。  相似文献   
229.
针对深孔复杂夹层(断层)和溶洞地层钻进的护壁困难,常规护壁方法无法解决的问题,提出并研究试验成功了高压旋喷水泥浆护壁技术,经多个矿区、钻孔的实践证明,高压旋喷水泥浆护壁法可以在任意孔深的坍塌超径孔段、软弱松散地层等形成可靠、有效的“水泥套管”护壁。系统介绍了该项技术的工艺原理、技术要点及其推广应用情况。  相似文献   
230.
代国忠  殷琨 《冰川冻土》2011,33(4):922-926
为研制出一种低渗透系数并对污染物有一定吸附阻滞作用的浆材,用于城市生活垃圾填埋场渗滤液防渗工程,通过正交试验优选出了以膨润土为主的浆材配方:膨润土20%~30%,水泥15%~25%,粉煤灰20%~25%,纯碱1.0%~1.4%,稀释剂FCLS加量0.35%~0.75%,余之为水.该浆材结石率〉99.6%,固结体28d渗...  相似文献   
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