Results 61 to 70 of about 1,245 (163)
Stability evaluation of karst roof of pile foundation based on variable weight fuzzy comprehensive theory [PDF]
Regarding the lower accuracy of the Analytic Hierarchy Process (AHP) in assessing the stability of karst cave roof under pile foundations, an improved structural model of evaluation indicators based on variable weight theory was developed to establish an
Xuewen HU, Yun’an LI, Zhigao FAN
core +1 more source
Shuitu Baochi Xuebao, 2023 为揭示工程堆积体平台汇流造成的水沙及氮磷养分流失特征,以矿区堆土场为研究对象,采用室内放水冲刷试验,研究不同上方来水流量(1.7,2.3,2.9 L/min)和坡度(25°,30°,35°)下地表径流、壤中流及侵蚀泥沙产生过程,分别测定氮磷养分浓度并计算流失量及贡献占比。结果表明:蒙东地区覆土排土场边坡产流方式主要为地表径流,随坡度和冲刷流量的增大,地表径流量增大,壤中流量减小。产沙量随坡度的增大先增大后减小,侵蚀产沙的临界坡度在30°附近。地表径流中铵态氮及磷酸盐流失浓度均大于壤中流 ...
樊桐桐 +4 more
doaj
Prospects for the development of the theory and technology of non-hydration penetration enhancement in soft coal seams [PDF]
In the future quite a long historical period, China will still adhere to the basic national conditions of coal. The efficient exploitation of coal, as a guarantee energy source, is crucial to China's energy security.
Changjiang CHEN +7 more
core +1 more source
Research progress of microbial reinforcement technology [PDF]
Biological reinforcement is a new branch that has developed in the field of engineering geology in recent years, among which, the microbially induced calcium carbonate precipitation (MICP) reinforcement technology is an effective method.
Long XU +5 more
core +1 more source
Shiyou jixie, 2014 水平井裸眼压裂技术是水平井增产的重要技术，球座是水平井压裂关键工具之一。通过建立球座的几何模型，采用Fluent软件，使用离散相模型和磨蚀模型对球座的磨损形态及流道两相流动状态进行数值分析。分析结果表明，在砂粒对球座的冲蚀磨损过程中，球座壁面处砂粒浓度越高，砂粒与壁面的撞击概率也越大，从而导致较为严重的冲蚀磨损；球座锥段处流道流通面积不断缩小，流场速度梯度变化最为强烈，从而导致部分砂粒脱离主流流线冲击球座锥面，产生冲蚀磨损现象。该项研究结果对球座的设计具有指导作用。
张磊 +4 more
doaj
, 2018 速凝水泥浆液黏度具有时变特性,流动过程中黏度时空分布不均匀。本研究通过实验测量速凝浆液的流变特性,建立该浆液的流变本构模型。考虑到速凝浆液物性参数随体变化,基于拉格朗日追踪方法,建立速凝浆液流动的数学模型。通过有限元数值模拟可以得到黏度,压力随时间变化的规律,对比数值结果与室内实验结果,验证该数学模型的适用性。对比传统方法,通过流量、压力、注浆能耗间的变化规律,验证了速凝浆液流动中采用拉格朗日追踪法描述流体物性参数随时间和空间变化的必要性。研究结果可为实际工程注浆参数的确定提供理论依据 ...
冯春, 杨田, 程鹏达
core
Characteristics of Geological Anomalies Shown on Seismic Time Sections [PDF]
With the rapid development of three-dimensional (3D) seismic exploration technology in recent years, its application has demonstrated significant advantages in interpreting the form and structure of underground coal seams, particularly in identifying ...
Xiaobing GENG
core +1 more source
Gaoya dianqi波纹铝护套由于具有良好的弯曲性能而被广泛用于高压交联聚乙烯（XLPE）绝缘电缆。然而，近年来发生了多起由缓冲层开始电缆烧蚀故障，严重的会发展到绝缘屏蔽层乃至于绝缘层。文中就径向电场引起的绝缘屏蔽的烧蚀机理展开研究，通过对不同间隙下绝缘屏蔽进行放电实验模拟，推导绝缘屏蔽烧蚀机理。实验结果表明，缓冲层发生烧蚀后会向内发展导致绝缘屏蔽烧蚀。有间距的情况下发生的击穿是缓冲层和绝缘屏蔽样品与电极之间的空气击穿，无间距的情况下，发生击穿是电极直接击穿缓冲层进而导致的绝缘屏蔽烧蚀 ...
叶宽 +8 more
doaj
Shuitu Baochi Xuebao, 1995 采用实验的方法，系统测定了苔藓层的抗冲性、抗雨蚀怀以及持水能力等方面的效益。结果表明：苔藓层对提高土壤抗冲怀具有极其显著的增强作用，且该作用随苔藓层的厚度增．加而增强，随着冲刷坡度的增大而减弱，在冲刷注０．９Ｌｍｉｎ的条件下，冲刷坡度小于或等于２０°时，２ｃｍ厚苔藓层厚度便能有效地控制水土流失；苔藓层对提高土壤抗雨蚀性具有明显的增强作用，从阻延径流的产时间，减少水土流失等方面体现出其强化性 ...
曾信波
doaj +2 more sources
Development and prospect of oil & gas pipeline engineering from the perspective of the philosophy of engineering [PDF]
Objective The emergence of the science-technology-engineering ternary framework symbolized the rise of the philosophy of engineering as a branch of the discipline of philosophy.
Pengchao CHEN, Zhongyuan GUAN
core +1 more source