低温条件下乙二醇基钻井液体系的试验研究

钻井液在冰点以下能否保持正常的工作性能对低温地层的勘探工作具有十分重要的意义,选择乙二醇作为钻井液的防冻剂可以满足勘探钻进工作的要求。对乙二醇复合聚合物钻井液的耐低温能力、流变性、失水特性以及钻井液的防塌能力进行了试验研究,确定了乙二醇及钻井液中其它聚合物的加量,使其满足低温条件下勘探的要求。     

用于空间目标表达的智能化判决方法

面对海量的空间目标,用户在感知空间态势过程中,需要解决"哪些空间目标需要表达出来,表达出来的目标中哪些需要重点表达"的问题。手工设置可以一定程度上满足需求,但是其过程复杂、繁琐。因此引入人工智能领域的智能代理和人工神经元网络来解决空间目标表达问题,分别将其应用于空间目标表达内容辅助筛选及重点目标确定上,共同完成空间目标的表达;并进行了实验验证。实验结果表明:Agent与神经网络结合可有效解决空间目标表达问题,并且具有一定的智能性。     

Coupled consolidation model for negative skin friction on piles in clay layers

Expansive soils swell on absorbing water and shrink on evaporation thereof. Because of this alternate swelling and shrinkage, civil engineering structures founded in them are severely damaged. For counteracting the problems of expansive soils, different innovative techniques were suggested. Stabilization of expansive clays with various additives has also met with considerable success. This paper presents, by comparison, the effect of lime and fly ash on free swell index (FSI), swell potential, swelling pressure, coefficient of consolidation, compression index, secondary consolidation characteristics and shear strength. Lime content was varied as 0%, 2%, 4%?and 6%?and fly ash content as 0%, 10%?and 20%. A fly ash content of 20%?showed significant reduction in swell potential, swelling pressure, compression index and secondary consolidation characteristics and resulted in increase in maximum dry density and shear strength. Swell potential and swelling pressure decreased with increase in lime content also. Further, consolidation characteristics improved. Compaction characteristics and unconfined compression strength improved at 4%?lime and reduced at 6%?lime.     

Effect of lime and fly ash on swell,consolidation and shear strength characteristics of expansive clays: a comparative study

Expansive soils swell on absorbing water and shrink on evaporation thereof. Because of this alternate swelling and shrinkage, civil engineering structures founded in them are severely damaged. For counteracting the problems of expansive soils, different innovative techniques were suggested. Stabilization of expansive clays with various additives has also met with considerable success. This paper presents, by comparison, the effect of lime and fly ash on free swell index (FSI), swell potential, swelling pressure, coefficient of consolidation, compression index, secondary consolidation characteristics and shear strength. Lime content (weight of lime/weight of dry soil) was varied as 0%, 2%, 4%?and 6%?and fly ash content (weight of fly ash/weight of dry soil) as 0%, 10%?and 20%. A fly ash content of 20%?showed significant reduction in swell potential, swelling pressure, compression index and secondary consolidation characteristics and resulted in increase in maximum dry density and shear strength. Swell potential and swelling pressure decreased with increase in lime content also. Further, consolidation characteristics improved. Compaction characteristics and unconfined compression strength improved at 4%?lime and reduced at 6%?lime.     

Effect of a cement-lignin agent on the shear behavior of Shanghai dredged marine soils

With the rapid urbanization in Shanghai, China, suitable fill materials have been reported to be in great shortage in recent years. A prospective solution to these issues is to convert the huge amount of existing dredged marine soils to construction materials via solidification. However, there have been no studies on the shear behavior of solidified dredged materials from Shanghai region so far, while it has been reported by various researchers that the available data obtained from certain types of clay cannot be confidently and readily applied to other types of soils. To address this challenging issue, in this article, samples of Shanghai marine dredged soils were retrieved from the world’s largest reclamation project in Shanghai Lin-gang New City. A series of laboratory tests have been conducted to investigate the shear behavior of Shanghai dredged marine soils solidified using a new composite curing agent made of cement and lignin. The test results and the effect of this cement–lignin agent on the shear behavior of Shanghai marine soils, including the stress–strain behavior, shear strength properties, and failure characteristics are presented and discussed, which can provide valuable reference for the use of dredged soils as construction materials in the Shanghai region.     

一种新的GIS智能分析框架——GIS智能体

提出了GIS智能体(GIS intelligent agent, GIS- IA)的概念、结构及实现原理。实例研究表明,基于GIS IA的智能分析框架是实现空间决策分析的一种有效途径。     

Utilization of a new soil stabilizer for silt subgrade

Silt cannot satisfy the requirements of highway construction because of its low strength. A new stabilizing agent (SEU-2) was developed to improve the mechanical performance and applicability of silt in road. Laboratory tests, including unconfined compression and shrinkage tests, were performed. Test results show that the new stabilizing agent can significantly increase the strength and the water stability, and decrease the shrinkage strain of silt. Field tests were also carried out and the results indicated that the new stabilizing agent could effectively improve the entire stiffness of subgrade. From the point of view in mechanics and applicability in road, adding 4% new stabilizing agent is an economic and reasonable method to stabilize the silt. The stabilized silt has high early strength, small shrinkage deformation, and high entire stiffness. It can satisfy the requirements of highway subgrades.     

水敏性地层钻探泥浆性能优化及配制

依据河南许昌地热井水敏性地层钻探工程,在分析水敏性地层的成分、水化机理及钻进泥浆性能需求的基础上,确定水敏性地层钻进需要滤失量小、密度低、流变性好、抑制性强的泥浆。依据文献资料及生产实践经验,初步选出配制泥浆的材料和浓度,采用室内试验测定泥浆性能和正交试验极差分析法优选泥浆材料浓度,优化出泥浆最终的配比,经生产实践验证调整,最终确定了适应项目生产需求的泥浆配方。经实际生产检验,满足水敏性地层钻探需求,效果良好。     

电解盐水杀菌技术在庄大污水处理站的研究应用

次氯酸钠作为消毒剂已在很多行业得到了广泛应用,作为油田污水处理用杀菌剂进行工业性试验还属首次。介绍了电解盐水现场产生次氯酸钠直接用于油田污水杀菌处理的技术原理、特点以及在大港油田庄大污水处理站的应用效果。并对次氯酸钠杀菌的加入浓度,以及对注水设备的腐蚀性进行了研究试验,结果表明次氯酸钠杀菌有很好的连续性,虽然杀菌后的污水腐蚀速率略有增加,但使用是安全的。     

膨胀土的电导率与膨胀性的关系研究

膨胀土是一种高塑性、强亲水的黏性土。由于黏土矿物含量较高,膨胀土颗粒的交换阳离子含量也较高,总比表面积较大,在电导率测试指标上反映是膨胀土的导电性随膨胀性的增大而增强。选取强、中、弱3种不同膨胀等级的代表性试样,采用无电极电阻率测定仪和便携式电导率探头,测试了膨胀土泥浆和孔隙水溶液电导率测试,采用原子吸收光谱仪检测了膨胀土孔隙水溶液中的离子种类、含量等。研究表明,膨胀土孔隙水溶液的导电性与膨胀土泥浆的导电性均随膨胀性增大而增大,膨胀土的电导率和自由膨胀率具有良好的线性关系,工程中可以利用这一原理进行膨胀土的快速判别。