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考虑地层蠕变效应的桥梁桩基施工对邻近运营地铁隧道的影响

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科学技术与工程 2024年第9期24卷 3781-3788页

作者：钱叶琳张振华崔文天苏颖奚邦禄徐恒晖安徽省路港工程有限责任公司合肥230022 合肥工业大学土木与水利工程学院合肥230009

为研究桥梁桩基施工引起地层蠕变效应对邻近地铁隧道安全运营的影响,采用卸荷条件下黏土蠕变特性试验确定了隧道周围土体的蠕变模型,通过数值仿真FLAC^(3D)与现场监测相结合的方法,分析了桩基开挖期间地铁隧道的竖向位移、水平位移和应... 详细信息

为研究桥梁桩基施工引起地层蠕变效应对邻近地铁隧道安全运营的影响,采用卸荷条件下黏土蠕变特性试验确定了隧道周围土体的蠕变模型,通过数值仿真FLAC^(3D)与现场监测相结合的方法,分析了桩基开挖期间地铁隧道的竖向位移、水平位移和应力分布状态。结果表明:广义Kelvin本构模型能够较为准确地描述黏土体开挖卸荷时的蠕变效应;桩基开挖后,邻近地铁隧道衬砌位移不断增大,随后进入稳定状态;随着桩基开挖数量的增加,地铁隧道竖向位移和水平位移总体表现为下沉和向外收敛趋势;桩-隧最小净距越小,桩基施工对隧道影响越大,采用隧道双侧布桩的施工方式,能够有效降低桩基开挖时隧道拱腰的累计水平位移,有利于地铁隧道的安全稳定运营。

关键词：桩基施工运营地铁地层蠕变隧道位移

Influence of h-BN particle size on fracture behavior and thermal shock resistance of Al2O3-C refractories

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Journal of Iron and Steel Research International 2022年第7期29卷 1129-1137页

作者： Zi-xu Ji Wen-jing Liu Ning Liao Ya-wei Li tian-bin Zhu The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina National-Provincial Joint Engineering Research Center of High Temperature Materials and lining Technology Wuhan 430081HubeiChina School of Chemical Engineering Qinghai UniversityXining 810016QinghaiChina

h-BN can be applied in Al_(2)O_(3)–C refractories to substitute graphite due to their similar crystal structure and better resistance to molten steel and *** effects of h-BN particle size on the mechanical properties and fracture behavior of Al_(2)O_(3)–C refractories were investigated through wedge splitting test and microstructural *** obtained results demonstrated that the addition of larger-sized h-BN was conducive to the growth of in situ formed SiC whiskers,which contributed to the highest flexural strength(42.63±3.10 MPa)of specimen *** comparison,the smaller-sized h-BN can induce more crack propagation paths along the interface and within matrix,leading to more tortuous crack propagation paths,and thus the thermal shock-related parameters such as specific fracture energy,characteristic length,and thermal shock resistance were ***,the residual strength ratio of Al_(2)O_(3)–C refractories was increased from 35.5%to 42.5%with decreasing the h-BN particle size from 10 to 0.1μm.

关键词： Al_(2)O_(3)–C refractory h-BN Fracture behavior Thermal shock resistance

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空气隙膜蒸馏系统膜面处流场特性研究

膜科学与技术 2015年第3期35卷 31-36页

作者：韩丽宁陈永艳田瑞蔚蕾内蒙古工业大学能源与动力工程学院呼和浩特010051 北奔重汽集团研发中心包头014020

利用高频PIV系统独有的高频特性,对空气隙膜蒸馏系统膜面处瞬态流场和湍流场进行了研究.由瞬态流场得到膜面附近流场中心涡从开始产生到变大再到逐渐消失的变化规律,对不同入流速度下膜面附近流场的湍流强度进行对比,得到膜面附近的瞬... 详细信息

利用高频PIV系统独有的高频特性,对空气隙膜蒸馏系统膜面处瞬态流场和湍流场进行了研究.由瞬态流场得到膜面附近流场中心涡从开始产生到变大再到逐渐消失的变化规律,对不同入流速度下膜面附近流场的湍流强度进行对比,得到膜面附近的瞬态流场和湍流强度随入流速度的变化趋势,为进一步研究空气隙膜蒸馏系统奠定了一定的数据和理论基础.

关键词：空气隙膜蒸馏高频PIV 瞬态流场

Analytical solution for steady seepage into a circular deep-buried mountain tunnel with grouted zone in anisotropic strata

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Journal of Mountain Science 2022年第10期19卷 2987-2998页

作者： YAN Qi-xiang ZHANG tian ZHANG Chuan GUO De-ping QING Song-yong Key Laboratory of Transportation Tunnel Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji UniversityShanghai 200092China Xuzhen Railway Co. Ltd.Zhaotong 657900China

Due to the existence of a large number of discontinuous fractures and interfaces in tunnel surrounding rocks,the groundwater inflow into tunnel generally presents significant ***,it is of great significance to consider the anisotropic permeability when dealing with water gushing-induced engineering accidents in water-rich mountain tunnels with large burial *** this study,based on the complex variable method and the seepage flow theory,a theoretical model of water inflow into a deep-buried circular tunnel in a fully saturated,anisotropic and semi-infinite aquifer is *** influence of grouted zone,initial support and secondary lining is fully *** comparison to the existing analytical methods and numerical results,the reliability of this proposed analytical solution is well *** is indicated from the parametric study that the groundwater inflow into tunnel presents an upward trend with an increasing value of the strata permeability in the vertical ***,the water inflow rate and the total water head decrease with the growth of the thickness of grouting *** is suggested that reasonable grouting thickness and permeability should be controlled to enhance the grouting *** study provides a practical method for estimating the water inflow into a deep-buried,grouted and lined mountain tunnel considering the anisotropic strata permeability.

关键词： Deep-buried tunnel Analytical solution Groundwater inflow Anisotropic strata Conformal mapping Grouted zone

空气隙膜蒸馏系统热容腔膜面处流场的数值模拟

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膜科学与技术 2014年第2期34卷 40-44,50页

作者：韩丽宁陈永艳田瑞杨晓宏内蒙古工业大学能源与动力工程学院呼和浩特010051

空气隙式膜蒸馏旋转切向入流利用出水口流体的切向流动对膜面进行冲刷,且不同的结构参数δ、β可加大靠近膜面流体的湍流强度,从而降低靠近膜面的边界层厚度即降低靠近膜面的浓度极化和温度极化现象,进而增大膜通量.利用Fluent软件可以... 详细信息

空气隙式膜蒸馏旋转切向入流利用出水口流体的切向流动对膜面进行冲刷,且不同的结构参数δ、β可加大靠近膜面流体的湍流强度,从而降低靠近膜面的边界层厚度即降低靠近膜面的浓度极化和温度极化现象,进而增大膜通量.利用Fluent软件可以模拟靠近膜面流体的流场、温度场、压力场等流体的流动情况.通过对比几组结构中靠近膜面流场的情况,可以推断出不同的β,δ以改变靠近膜面的浓度极化和温差极化现象.从而得到热容腔的最优结构.

关键词：空气隙膜蒸馏旋转入流数值模拟

土体渗透各向异性对水下隧道渗流量的影响研究

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地基处理 2024年第1期6卷 8-15页

作者：乔彤周建张天骄蒋熠诚浙江大学滨海和城市岩土工程研究中心浙江杭州310058

本文以考虑衬砌作用的水下隧道模型为依托,同时考虑隧道洞周土竖向和侧向渗透性差异,结合坐标变换、保角映射法,推导了考虑衬砌等水压和等水头渗水模式下的渗透各向异性水下圆形隧道渗流量解析解式,通过数值模拟分析验证了解析解的正确... 详细信息

本文以考虑衬砌作用的水下隧道模型为依托,同时考虑隧道洞周土竖向和侧向渗透性差异,结合坐标变换、保角映射法,推导了考虑衬砌等水压和等水头渗水模式下的渗透各向异性水下圆形隧道渗流量解析解式,通过数值模拟分析验证了解析解的正确性。此外分析了衬砌渗水模式、衬砌渗透性、隧道埋深、弱透水体、地表压力水头高度对隧道渗流量的影响。研究表明,渗透各向异性会影响隧道渗流量,忽略洞周土体渗透各向异性将低估隧道渗流量,尤其是渗透各向异性能够改变浅埋隧道中水流的渗流路径,对浅埋隧道渗流量的影响更显著;等水压和等水头渗水模式下的隧道渗流量随隧道埋深的增大而趋于一致,浅埋隧道考虑衬砌渗水模式更有意义;衬砌能够削弱渗透各向异性对渗流量的影响,削弱能力随衬砌渗透性的降低而增强;软黏土等弱透水土体中考虑渗透各向异性对渗流量的影响更大,地表压力水头越大,隧道渗流量越大,渗透各向异性对于隧道渗流量的影响也越明显。

关键词：各向异性渗流渗水模式保角映射解析解渗流量衬砌

双螺杆挤压对玉米重组米理化特性及品质特性的影响

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食品科学 2019年第17期40卷 183-189页

作者：谢天孙洪蕊康立宁李凤林田志刚刘香英吉林省农业科学院农产品加工研究所吉林长春130022 吉林农业科技学院食品科学与工程学院吉林吉林132101

为研究双螺杆挤压技术对玉米粉挤压前后理化特性及品质特性的影响,采用SLG-30双螺杆挤压机对吉林省17个品种玉米进行挤压膨化,对双螺杆挤压处理前后重组米理化特性及品质特性进行分析。结果表明,挤压处理后不同品种玉米粉的蛋白质量分... 详细信息

为研究双螺杆挤压技术对玉米粉挤压前后理化特性及品质特性的影响,采用SLG-30双螺杆挤压机对吉林省17个品种玉米进行挤压膨化,对双螺杆挤压处理前后重组米理化特性及品质特性进行分析。结果表明,挤压处理后不同品种玉米粉的蛋白质量分数平均降低11.32%,脂肪质量分数平均降低29.88%,直链淀粉质量分数平均降低5.11%,冻融稳定性平均提高58.90%,糊化度平均提高88.62%,吸水性平均提高77.03%,水溶性平均提高73.57%,膨润力平均提高87.51%。相关性分析表明,挤压处理后糊化度与脂肪、直链淀粉、蛋白质量分数均呈负相关,与吸水性和水溶性均呈极显著正相关(P<0.01);直链淀粉、脂肪质量分数与冻融稳定性、糊化度、吸水性和水溶性均呈极显著负相关(P<0.01)。挤压处理对玉米的理化特性指标有负面影响,但能明显提高产品加工性能和食用特性。

关键词：双螺杆挤压技术重组米理化特性品质

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大型炼油厂轻烃回收流程整合的探讨

炼油技术与工程 2008年第2期38卷 11-14页

作者：李宁王青宁王德会朱颖田静兰州理工大学甘肃省兰州市730050 中国石油华东设计院山东省青岛市266071

提出将产生饱和烃炼厂气的装置的轻烃回收部分进行整合,结合Aspen Plus软件的模拟结果对整合的范围、是否设压缩机、吸收塔吸收油的选择、干气抽出位置、脱硫部分、换热流程优化等进行了初步的探讨。新的设计不仅节约了投资而且降低了... 详细信息

提出将产生饱和烃炼厂气的装置的轻烃回收部分进行整合,结合Aspen Plus软件的模拟结果对整合的范围、是否设压缩机、吸收塔吸收油的选择、干气抽出位置、脱硫部分、换热流程优化等进行了初步的探讨。新的设计不仅节约了投资而且降低了能耗。

关键词：轻烃回收整合流程液化石油气干气 Aspen plus

Diagenetic fluids evolution of Oligocene Huagang Formation sandstone reservoir in the south of Xihu Sag, the East China Sea Shelf Basin： constraints from petrology, mineralogy,and isotope geochemistry

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Acta Oceanologica Sinica 2018年第2期37卷 25-34页

作者： HAO Lewei WANG Qi GUO Ruiliang TUO Chengrong MA Dongxu MOU Weiwei tian Bing Key Laboratory of Petroleum Resources Gansu Province/Key Laboratory of Petroleum Resources Research Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China University of Chinese Academy of Sciences Beijing 100049 China

The Oligocene Huagang Formation is the main sandstone reservoir in the Xihu Sag, situated in the east of the East China Sea Shelf Basin. With an integrated approach of thin-section petrography, ultra-violet fluorescence microscopy, scanning electron microscopy, and isotope geochemistry, the different diagenetic features were identified, the typical diagenetic parasequences were established, and the diagenetic fluids evolution history were reconstructed for the Oligocene Huagang Formation sandstone reservoir in the south of Xihu Sag. The Huagang Formation sandstone reservoir is now in Period B of the mesodiagenesis, which has undergone significant diagenetic alterations such as mechanical compaction, Pore-lining chlorite cement, feldspar dissolution, quartz cementation and dissolution, and carbonate cementation. Three types of carbonate cements（early siderite,medium ferrocalcite and late ankerite） were identified in the Huagang Formation sandstone reservoir. The carbon and oxygen isotopic compositions of carbonate cements show that the early calcite precipitate from alkaline lacustrine environment whereas the late carbonate cements were closely related to the organic acids. To the Huagang Formation sandstone reservoir, it has experienced two main episodes of dissolution during *** early dissolution is that unstable components such as feldspar, lithic fragments, and carbonate cement were dissolved by acidic water. The second dissolution is that quartz and other silicate minerals were dissolved under the alkaline condition. Two main phases of hydrocarbon charging occurred in this study area. The first hydrocarbon emplacement was prior to the medium carbonate cementation but posterior to feldspar dissolution and the onset of quartz cementation at the end of the Miocene. The second hydrocarbon charging occurred in the Quaternary period after the late carbonate precipitation.

关键词： diagenesis fluid evolution Huagang Formation Xihu Sag