排序方式： 共有38条查询结果，搜索用时 15 毫秒
31.
32.
砂砾岩地层是钻井工程中的难钻地层,如何提高砂砾岩地层的钻进效率和钻头寿命一直是工程实践中的重要问题。针对在元坝地区珍珠冲石英砂砾岩地层钻进过程中,使用普通型牙轮钻头外排齿易早期断齿、综合使用指标低的问题,开展了地层岩性、钻头使用与失效分析。针对性地开展了钻头的切削结构、齿材优化以及加强保径等方面的研究,优化设计、研制出HJT547GKL型新型三牙轮钻头。现场试用结果表明,这种新型牙轮钻头在元坝地区珍珠冲组石英砂砾岩地层钻进中有较高的行程进尺。该钻头是一种结构简单、扶正保径好、可靠实用,适用于较硬、有硬夹地层的新型实用三牙轮钻头。 相似文献
33.
水泥基土壤固化剂固化土的物理化学作用 总被引：1，自引：0，他引：1
采用击实试验、液塑限联合测定界限含水率试验、蜡封法测定干密度试验、二氧化碳气量法、交换性钠离子百分比试验等方法,结合黏土矿物组成与结构特点,研究了水泥基土壤固化剂固化土的物理化学作用。试验结果表明：随着固化剂剂量的增加,混合料的最大干密度增大,最优含水率降低;固化土混合料经过养护后,塑性指数降低,干密度增大,碳酸盐含量增加,交换性钠离子百分比升高;黏土矿物在强碱性和钙离子作用下被激活,形成各种水化硅酸盐和铝酸盐。研究认为：在土-固化剂-水-气系统中通过液相和气相向固相的转变以及各类水化产物的填充、挤密、胶结等作用,混合料逐渐形成较致密的整体;离子交换反应对土体的加固作用在后期起负效应;铝硅酸盐黏土矿物在强碱性和钙离子存在条件下被分解,参与水化硅酸盐和铝酸盐的反应。 相似文献
34.
BS-100型土壤固化剂在季冻区的路用性能试验研究 总被引：9，自引：0，他引：9
采用美国Base-Seal固化剂（BS-100型）,对长春地区典型黏性土进行了固化处理,同时对其加固土的路用性能进行了系统地试验研究。首先,进行了Base-Seal固化剂加固土的最佳配合比筛选试验,在此基础上进行了最佳配合比条件下加固土的无侧限抗压强度、间接抗拉强度、室内回弹模量、冻稳定性、水稳定性和渗透性等路用性能指标方面的试验研究,得出Base-Seal固化剂加固土作为路面基层材料具有早期强度和回弹模量高、抗弯拉性能、冻稳定性能、水稳定性能和抗渗性能好的结论,适合在长春地区及其气候、土质相似地区的道路工程中应用。 相似文献
35.
以天然钙蒙脱土为研究对象,采用不同浓度的离子固化剂对其进行改性处理,开展素土与改性蒙脱土在相对湿度（P/P0）0～0.95区间的水汽等温吸-脱附试验,通过吸附速率曲线、晶层间距d001值变化曲线分析蒙脱土水合机制,并采用蒙脱土孔隙比变化曲线关联分析水合-孔隙演化规律,提出不同尺度孔隙吸附水的界限相对湿度区间。在此基础上,基于X射线衍射(XRD)、氮气吸附以及压汞试验对离子固化剂改性蒙脱土水合过程的孔隙分布特征进行验证分析。试验结果表明：对于钙蒙脱土,00.8～0.9时,黏土颗粒表面持续吸附弱结合水,此时大孔内逐渐充填水分。离子固化剂通过改变蒙脱土的微观物理化学性质（阳离子与晶层基面）调控其吸附水特性,进而影响不同尺度孔隙的吸附水过程。 相似文献
36.
The quantity of the by-product olive cake residue generated in most parts of the Mediterranean countries continues to increase and expected to double in amount within 10–15 years. This increase intensifies the problems associated with the disposal of this by-product. Olive cake residue has a potential for use as a soil stabilizer and large volumes can be beneficially used. This study is directed toward determining if olive cake residue can be utilized to increase the strength and stability of expansive soils which constitute a costly natural hazard to lightweight structures on shallow foundations. A series of laboratory tests using engineering properties, such as Atterberg limits, moisture-density relationship (compaction), swell, unconfined compressive strength were undertaken to evaluate the effectiveness and performance of the olive cake residue as a soil stabilizer. Test results indicate that an addition of only 3% burned olive waste into the soil causes a reduction in plasticity, volume change and an increase in the unconfined compressive strength. However, it was observed that the presence of burned olive waste in the soil greater than 3% caused an increase in the compressibility and a decrease in the unconfined compressive strength. Test results indicate that the use of olive waste in soil stabilization gives greater benefits to the environment than simply disposing of the by-product, olive cake residue. 相似文献
37.
离子固化剂(ISS)对膨胀土改良后,膨胀土稳定性会改善。为了分析研究不同初始含水率的膨胀土经过ISS改良效果,进行了膨胀土改良前后的剪切试验、界限含水率试验和自由膨胀率试验。通过改良前、后土体的抗剪强度、塑限、液限、塑限指数、自由膨胀率的变化规律研究,得出膨胀土的初始含水率在11%～30%区间时,改良后土体的膨胀性得到了消除,抗剪强度得到了明显提高; 初始含水率不在11%～30%区间时土样改良后仍具有一定膨胀性,抗剪强度提高不明显。这是因为,当膨胀土烘干时,靠毛细吸力吸附的固化剂量不能与所有黏土颗粒进行反应; 当膨胀土饱和时,靠溶液渗透到膨胀土表面的固化剂也不能与所有黏土颗粒进行反应。该试验结果对膨胀土现场改良时含水率的确定具有重要的指导意义。 相似文献
38.
Shuangxi Ji Huai Zhang Yanfei Wang Liangliang Rong Yaolin Shi Yongshun Chen 《Geophysical Prospecting》2019,67(1):226-261
Rapid developments in SQUID-based technology make it possible for geophysical exploration to direct measure, inverse and interpret magnetic gradient tensor data. This contribution introduces a novel three-dimensional hybrid regularization method for inversion of magnetic gradient tensor data, which is based on the minimum support functional and total variation functional. Compared to the existing stabilizers, for example, the minimum support stabilizer, the minimum gradient support stabilizer or the total variation stabilizer, our proposed hybrid stabilizer, in association with boundary penalization, improves the revision result greatly, including higher spatial and depth resolution, more clear boundaries, more highlighted images and more evident structure depiction. Moreover, suitable selection of model parameter λ will further improve the image quality of the recovered model. We verify our proposed hybrid method with various synthetic magnetic models. Experiment results prove that this method gives more accurate results, exhibiting advantages of less computational costs even when less prior information of magnetic sources are provided. Comparison of results with different types of magnetic data with and without remanence indicates that our inversion algorithm can obtain more detailed information on the source structure based on rational estimation of total magnetization direction. Finally, we present a case study for inverting SQUID-based magnetic tensor data acquired at Da Hinggan Mountains area, inner Mongolia, China. The result also certifies that the method is reliable and efficient for real cases. 相似文献