煤矿采空区充填墩台承载特性试验

高浓度浆液注入到采空区后形成充填墩台,墩台搭接尺寸将影响其上覆承载力。为掌握搭接尺寸对上覆承载力影响规律,选取水泥为胶结材料,标准砂为骨料,配制高浓度浆液,并利用3D打印技术制模制作墩台试样,进行单轴抗压试验。结果表明,单个墩台在顶面面积和高度一定时堆积角度越小极限承载力越大;堆积角30°和45°的搭接墩台试样的极限承载能力均在对应的单个墩台的2.0~3.5倍范围,试样硬化后,搭接墩台试样的极限承载力随着搭接尺寸的增加呈先增大后减小的趋势;采用墩台充填的方式进行采空区治理时,合理设置注浆孔间距,使所注浆液在采空区内部形成搭接墩台群,其承载效果优于均匀分布的单个墩台;堆积角30°搭接墩台的场地承载力整体优于堆积角45°的搭接墩台;采空区内取充填堆积角30°搭接墩台,且注浆孔间距为极限搭接尺寸的38.5%时,治理场地内整体承载力最大。研究成果将为高浓度浆液部分充填治理采空区的工程实施提供依据。     

热德拜油田水平井优快钻井配套技术

为加快热德拜油田水平井钻井开发步伐,通过对岩石力学特性、岩石理化特性、井眼轨道、钻具组合、钻头选型等方面的研究,形成了以PDC钻头复合钻井技术、井眼轨迹控制技术、防漏堵漏钻井液技术、筛管顶部双级注水泥固井技术等为主的科学、合理的配套工艺技术,并应用于现场施工,加快了热德拜水平井开发步伐,节约了开发成本。2012年水平井平均钻井周期为42.96天,完井周期53.38天;2013年水平井平均钻井缩短至19.58天;完井周期37天,同比钻井周期缩短54.4％,完井周期缩短41.1％。     

边坡堆积体锚索防腐及注浆工艺探讨

通过在海南石碌铁矿采场边坡地质灾害治理工程施工实例,探讨在堆积体预应力锚索防腐及注浆工艺的施工方法。为今后在堆积体锚索防腐及注浆的施工提供参考。     

页岩气钻完井配套技术集成研究与应用

随着涪陵页岩气田100×108 m3/a产能建设、长宁-威远国家级页岩气产业示范区等区块页岩气的高效勘探开发,我国的能源结构也在不断地改变。页岩气的商业化开发有赖于丛式水平井钻井技术及大型分段压裂技术的不断发展和进步,高效的钻完井配套技术是提高页岩气勘探开发效果的有力保障。中原石油工程公司通过自主攻关和集成配套相关钻井新工艺、新工具,在钻井实践中取得了一系列技术突破,形成了三维大偏移距长水平段水平井轨迹控制技术、油基乳化/无土相油基钻井液技术、防漏堵漏技术、页岩气随钻解释评价技术、油基钻井液高效冲洗技术、“井工厂拉链式”压裂技术、高压网电配套工程技术等关键技术。上述技术在川渝的涪陵、长宁-威远、永川等工区140余口井的成功应用,有效支撑了我国页岩气产能建设。本文基于中原工程页岩气钻完井配套技术的攻关及实钻经验总结,对其他页岩气勘探开发区块的钻完井工程具有较强的指导意义。     

漏失量较大地层“戴帽”固井技术

对漏失量较大的岩溶地层进行“戴帽”固井时,由于打完水泥浆后注入替浆水的过程中及后期稳定液面变化很容易造成水泥浆被稀释,前者直接导致固井失败,后者又受很多因素的影响导致重叠管环空内没有水泥浆或者被稀释而形不成水泥塞。本文主要从钻杆下入位置以及注入替浆水的过程中和后期稳定液面变化这几个方面总结“戴帽”固井的关键,并结合工程实例提出了一些人为控制方法来提高固井的成功率。     

泥水盾构泥浆泵选型关键参数规律性研究

为了认清在泥水盾构泥浆泵选型设计时的规律性和差异性,针对现有研究的不足,采用统计分析法,从15个实际工程案例入手,统计了包括开挖直径、隧道长度、穿越主要地层、进排泥的管径、密度和流量在内的17个关键参数,分析在选型设计阶段关键参数之间的规律性和差异性,得到了进排泥的管径、密度与开挖直径的一次线性回归方程,不同地层的进排泥密度选取规律等6点结论,最后将结论成功运用于福州地铁F1线滨海新城站—机场站中间风井泥水盾构区间,研究成果可为今后泥浆泵选型或评估提供新的思路。     

鄂尔多斯盆地西南缘供水井质量恶化原因分析及对策

作为极度缺水的鄂尔多斯盆地西南缘地区,针对白垩系含水地层采水的供水井很多,但供水井水质恶化和水量减小的现象较为普遍,其原因主要是井身结构严重不合理所致。通过对造成供水井质量恶化的原因分析,找出了止水方法的不合理性与泥岩缩径造成井身变形而致水量减小的问题实质,提出了科学合理的成井方案,从而有效地解决了供水井质量恶化问题,提高了供水井使用寿命。     

Effect of the pressurized duration on improving dredged slurry with air booster vacuum preloading

Abstract

Compared with traditional vacuum preloading, air booster vacuum preloading is more effective at strengthening dredged slurry and improving the consolidation process. Although many engineering practices have shown that the pressurized duration has a significant effect on the reinforcement effect, there is no standard available for determining the pressurized duration. In this study, five dredged slurry samples were tested to examine the effect of different pressurized durations on the consolidation. An extensive monitoring system was used to measure the vacuum pressure, pore water pressure, settlement, and water discharge during the test, while the water content and shear strength were measured after the test. The collected monitoring data were comprehensively analyzed to evaluate the reinforcement effect. The results revealed that the pressurization system can be used to reinforce deep dredged slurry and make the whole soil layer more homogeneous. If the pressurized duration is too short, the dissipation of pore water pressure is too little to achieve the pressurization effect. If the pressurized duration is too long, too much gas will be in the soil and enter the vacuum system, which will significantly reduce the vacuum pressure and thus the reinforcement effect. Based on these findings, the optimal pressurized duration was obtained.     

Research and application of mud proportioning optimization of slurry balance shield in mudstone and gravel composite stratum

Slurry performance is one of the key factors to maintain the stability of excavation face when slurry balance shield is tunneling in complex strata. Based on the engineering background of slurry shield tunneling in mudstone and gravel composite stratum of Nanning Metro Line 5, the control variable method and the self-made slurry shield tunneling system are adopted to compare and select the mud admixture and to analyze the influence of the admixture amount and the formation composite ratio on the slurry relative density. Then, the mud permeability law and the dynamic and static mud film forming law under different formation composite ratios, swelling water ratios and slag dosages are analyzed comprehensively by factorial design. The results show that different admixtures have significant influence on the properties of bentonite slurry. Specifically, potassium methyl silicate and potassium chloride can effectively reduce the relative density of slurry, while sodium chloride and sodium silicate can promote the disintegration of mudstone in water. In addition, the slag admixture can effectively reduce the water filtration, improving the film quality and reducing the consumption of bentonite. When the cutter head speed is less than or equal to 2.5 r/min, the formation rate of mud film is greater than or equal to the failure rate so as to ensure the stability of driving face. The mud swelling water ratio suitable for mudstone and gravel composite stratum (composite ratio: 0?1) is 0.1?0.20, the residue content is 100?200 g/kg, and the potassium methyl silicate is 3.75%?7.50%.     

富水圆砾层地铁联络通道综合灌浆防渗加固处理

南宁某地铁联络通道（兼废水泵房）洞身大部分位于富水圆砾层中,前期采用了地下连续墙+袖阀管灌浆的防渗加固处理措施,但未能达到预期处理目的。针对该联络通道圆砾层厚度大、透水性强、自稳性差等特点和难点,研究提出了地表水泥膏浆结合稳定性浆液加固+洞内AC-MS丙烯酸盐化学灌浆防渗的综合灌浆方案,成功解决了该富水圆砾层的防渗加固难题。开挖及监测结果表明富水圆砾层经综合灌浆处理后颗粒胶结良好,固结体坚硬、密实,围岩稳定、渗透性显著减小,开挖过程中未发生坍塌、失稳和涌水、涌泥等现象,防渗加固效果显著,可供类似工程参考。