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基于SILL的阿拉伯留学生在华英语学习策略实证研究
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作者 刘中阳 Samar Sayed 《教育教学论坛》 2023年第44期30-35,共6页
我国高校阿拉伯留学生的数量不断增加,英语作为其日常学习交流的主要语言,重要性不言而喻。通过Oxford语言学习策略量表(SILL),对阿拉伯留学生英语学习过程中的元认知、认知、社交、补偿、情感、记忆等六个方面策略的使用频率,了解阿拉... 我国高校阿拉伯留学生的数量不断增加,英语作为其日常学习交流的主要语言,重要性不言而喻。通过Oxford语言学习策略量表(SILL),对阿拉伯留学生英语学习过程中的元认知、认知、社交、补偿、情感、记忆等六个方面策略的使用频率,了解阿拉伯留学生在我国这样的非英语国家进行专业课程学习时的英语学习策略,结果发现元认知策略是最常用的策略,而记忆策略很少被主动用到。因此,在英语课堂上,教师可以考虑充分调动学生的积极性,使其日常所用和所学相结合,进一步提升学习效果。 展开更多
关键词 阿拉伯留学生 sill 英语学习策略 中国 EFL
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SILLS软件在单个萤石流体包裹体LA-ICP-MS微量元素分析数据处理中的应用 被引量:1
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作者 李阳 邹灏 +2 位作者 刘行 蒋修未 李蝶 《岩矿测试》 CAS CSCD 北大核心 2020年第2期300-310,共11页
近年来激光剥蚀电感耦合等离子体质谱(LA-ICP-MS)应用于单个流体包裹体成分定量分析已成为研究流体包裹体的最佳手段之一。该实验过程和数据处理比较复杂,目前国内外采用的数据分析软件为一款基于MATLAB的SILLS软件,该软件主要是对矿物... 近年来激光剥蚀电感耦合等离子体质谱(LA-ICP-MS)应用于单个流体包裹体成分定量分析已成为研究流体包裹体的最佳手段之一。该实验过程和数据处理比较复杂,目前国内外采用的数据分析软件为一款基于MATLAB的SILLS软件,该软件主要是对矿物(锆石)、流体包裹体以及熔体包裹体LA-ICP-MS分析结果进行处理。本文以萤石流体包裹体LA-ICP-MS分析为例,阐述了样品制备与流体包裹体的优选方法,对流体包裹体片厚度以及单个流体包裹体的选取要求作了详细描述,对仪器参数设置、内外标样选取和剥蚀方法等进行了说明。基于SILLS软件采用尖峰消除的方法对待处理数据进行校正,对不同种类型的波峰进行峰宽的选取。在元素比值校正和等效盐度计算过程中,由于被测样品是萤石,Ca元素具有较高的背景值,选择以Na作为流体包裹体的内标元素,以Ca作为寄主矿物的内标元素对寄主矿物浓度进行计算,同时提出以电价平衡代替质量平衡进行等效盐度计算。以上方案提高了LA-ICP-MS分析单个萤石流体包裹体的准确性,有助于解释成矿流体来源和矿床成因等问题。 展开更多
关键词 LA-ICP-MS 单个流体包裹体 sillS软件 定量分析 数据处理
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Fingered Intrusion of Shallow Saucer-shaped Igneous Sills: Insights from the Jiaojiang Sag, East China Sea 被引量:8
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作者 GUO Rui ZHANG Gongcheng +4 位作者 ZHANG Jinwei ZHAO Xingbin LIU Junbang YUAN Dawei SONG Shuang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第5期1306-1318,共13页
An extensive suite of igneous sills was intruded into the Tertiary sedimentary section of the Jiaojiang sag, East China Sea. This suite has been well imaged offshore through 2D and 3D seismic surveys, showing a close ... An extensive suite of igneous sills was intruded into the Tertiary sedimentary section of the Jiaojiang sag, East China Sea. This suite has been well imaged offshore through 2D and 3D seismic surveys, showing a close relationship with CO2 content in nearby gas discoveries. A new observational model, which incorporates simple upward propagation, simple horizontal propagation, and transgressive propagation, was proposed to interpret these sill intrusions. In this model, the source magma of the saucer-shaped sills was injected from their lowest points near the center. The transgressive propagation can be interpreted as a combination of the vertical and horizontal propagation. Most shallow sub-volcanic intrusions in the Jiaojiang sag exhibit fingered characteristics, both vertically and horizontally. The vertical fingered propagation produced saucer-shaped sills arranged in the flower style. Along the brims of lower sills could usually be found the upper sills, which are interpreted to have formed simultaneously with or later than the lower feeder sills. In the second type, the chilled paths of the older sills were reutilized by subsequent intrusions. The horizontal fingered propagation formed sheet intrusions that exhibit groove, lobate, tubular, and crevasse splay- like geometry in plan view. In 3D view, the sheet intrusions have still preserved the lower center and higher rim that similar with the sub-rounded saucer-shaped sills. Although fracture propagation may be important, flow inflation was the key mechanism of magma intrusion. Further consideration of the mechanisms underlying sill formation may help explain the fingered characteristics of sill propagation. 展开更多
关键词 Saucer-shaped sill fingered intrusion feeder relationship lobate sill flow inflation Jiaojiang sag
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SILL语言学习策略量表的信度研究 被引量:1
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作者 徐爽 《贵州教育学院学报》 2008年第4期68-70,共3页
SILL语言学习策略量表在语言学习策略研究中被大量的使用。针对其在中国使用的具体情况对该量袁的信度进行了探索性的研究,以期对SILL语言学习策略量表在中国大学生中的使用提供更为可靠的依据。
关键词 语言学习策略 sill量表 信度
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SILL在少数民族地区初中英语学生中的应用
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作者 孙霞 韦启卫 《英语广场(学术研究)》 2016年第11期138-140,共3页
本文综述国内外学者对学习策略的理解,以Oxford(1990)语言学习测量表(Strategy Inventory for Language Learning)为测量工具,以民族地区某中学初三年级学生为研究对象,探讨了三个问题,即该校初三年级学生使用英语学习策略特征,分析SIL... 本文综述国内外学者对学习策略的理解,以Oxford(1990)语言学习测量表(Strategy Inventory for Language Learning)为测量工具,以民族地区某中学初三年级学生为研究对象,探讨了三个问题,即该校初三年级学生使用英语学习策略特征,分析SILL信度差异及英语学习策略与初三年级英语毕业考试成绩之间的关系。笔者同时提出如何因地制宜地运用学习策略,提高少数民族地区中学英语教学质量的建设性意见。 展开更多
关键词 sill 学习策略特征 信度 关系
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Petrogenesis of the~2115 Ma Haicheng Mafic Sills in the Eastern North China Craton and Their Implications for An Intra-Continental Rifting 被引量:28
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作者 WANG Xinping PENG Peng +1 位作者 WANG Chong YANG Shuyan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期128-,共1页
It is well known that there are widespread igneous events at;100 Ma in the Eastern North China Craton;however,their tectonic environments are controversial.They were thought to be either related to an intra-continenta... It is well known that there are widespread igneous events at;100 Ma in the Eastern North China Craton;however,their tectonic environments are controversial.They were thought to be either related to an intra-continental rifting or 展开更多
关键词 Ma Haicheng Mafic sills in the Eastern North China Craton and Their Implications for An Intra-Continental Rifting Petrogenesis of the
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Numerical investigation of the stresses in backfilled stopes overlying a sill mat 被引量:2
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作者 Mohamed Amine Sobhi Li Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2017年第3期108-119,共12页
Backfill is commonly used in underground mines to help increase the ore recovery rate and reduce the ore dilution. The use of a part of mine waste as underground backfill material also helps reduce the environmental i... Backfill is commonly used in underground mines to help increase the ore recovery rate and reduce the ore dilution. The use of a part of mine waste as underground backfill material also helps reduce the environmental impact of mining operations. After all, backfill is used to provide a working platform or safer working space. Its primary and most important role is to improve the rock mass stability around mine openings. However, most available solutions to stress analyses were developed for an isolated stope, without taking into account the influence of mine depth, or of adjacent stopes. In this paper,results from a numerical study carried out to evaluate the stresses in backfilled stopes overlying a sill mat are presented. Mine depth and excavation of the underlying stope below the sill mat(horizontal pillar)are both taken into consideration. The influence of stope geometry, backfill, sill mat and rock properties on the stresses is also evaluated. Compared with the case of a single isolated backfilled stope, the numerical results show that the stress magnitudes in the overlying backfill are considerably increased due to the excavation of the underlying stope. In general, the stresses also increase with mine depth and backfill stiffness, while these tend to decrease with an increase in the surrounding rock mass stiffness.These results suggest that existing solutions for backfill design may need to be revised. 展开更多
关键词 Mine depth Backfill sill mat Stresses Numerical modeling
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Early Eocene leucocratic sill/dike swarms in the Gangdese belt, southern Tibet: Tectonic implications for Indo-Asian collision 被引量:4
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作者 Xu-xuan Ma Li-E Gao +2 位作者 Zhong-bao Zhao Xi-jie Chen Hai-bing Li 《China Geology》 2021年第1期56-66,共11页
The timing of the initial Indo-Asian collision is a subject of debate for a long time.Besides,the magmatic trace of the collisional process is also unclear.In the present study,the authors report Early Eocene leucocra... The timing of the initial Indo-Asian collision is a subject of debate for a long time.Besides,the magmatic trace of the collisional process is also unclear.In the present study,the authors report Early Eocene leucocratic sill/dike swarms in the northern edge of the Nymo intrusive complex of the Gangdese belt,southern Tibet.The Nymo intrusive complex was emplaced at ca.50–47 Ma and surrounded by the metamorphosed Jurassic-aged Bima Formation volcano-sedimentary sequence along its northern side.At outcrops,the leucocratic sills/dikes intruded along or truncated the deformed foliations of the host Bima Formation,which has been subject to high-temperature amphibolite-facies metamorphism at ca.50–47 Ma.Detailed cathodoluminescence image analyses reveal that the zircon grains of the leucocratic sills/dikes have core-mantle textures.The cores yield the Jurassic ages comparable to the protolith ages of the Bima Formation.In contrast,the mantles of zircon grains yield weighted mean ages of ca.49–47 Ma,representing the crystallization timing of these leucocratic sills/dikes.The coeval ages for the Nymo intrusive complex,the high-temperature metamorphism,and the leucocratic sills/dikes indicate that a close relationship exists among them.The authors tentatively suggest that these leucocratic sills/dikes were generated from partial melting of the Jurassic-aged Bima Formation volcanic rocks,triggered by the high heat from the magma chamber of the Nymo intrusive complex.This Early Eocene tectono-thermal event of coeval magmatism,metamorphism and partial melting was most likely formed during the Indo-Asian collisional setting. 展开更多
关键词 Leucocratic sill/dike swarm Early Eocene Indo-Asian collision GANGDESE Tibet China
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Strategic sill pillar design for reduced hanging wall overbreak in longhole mining 被引量:1
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作者 Tuo Chen Hani S.Mitri 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第5期975-982,共8页
Steeply dipping,vein and tabular orebodies are traditionally extracted with longitudinal retreat mining methods such as Eureka and Avoca in a bottom-up sequence with delayed backfill.To increase productivity,sill pill... Steeply dipping,vein and tabular orebodies are traditionally extracted with longitudinal retreat mining methods such as Eureka and Avoca in a bottom-up sequence with delayed backfill.To increase productivity,sill pillars in the orebody are used to separate mining zones thus allowing production to take place simultaneously in two or more zones.While such mining methods are productive,they may be accompanied with high volumes of hanging wall overbreak causing significant unplanned ore dilution.In this work,it is shown through a mine design case study of a narrow vein deposit that a sill pillar could also play a significant role in limiting hanging wall overbreak.To demonstrate the role of sill pillar,a novel numerical modelling scheme is proposed to account for progressive stope wall overbreak.A numerical modelling approach of element death and rebirth is developed to allow for the detected stope overbreak to be immediately removed and replaced with backfill material before upper-level stope extraction.It is further shown that the average overbreak volume could be reduced by as much as 33%when the sill pillar is strategically placed in the lower half of a mine plan. 展开更多
关键词 Underground mine design Longitudinal mining sill pillar design Unplanned ore dilution Numerical modelling
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Characteristics of a Drainage Channel with Staggered Indented Sills for Controlling Debris Flows 被引量:4
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作者 CHEN Xiao-qing YOU Yong +2 位作者 CHEN Jian-gang HUANG Kai LI De-ji 《Journal of Mountain Science》 SCIE CSCD 2014年第5期1242-1252,共11页
The characteristics of a new type of drainage channel with staggered indented sills for controlling debris flows were studied. The intermediate fluid in the non-viscous debris flow exhibited a helical movement, wherea... The characteristics of a new type of drainage channel with staggered indented sills for controlling debris flows were studied. The intermediate fluid in the non-viscous debris flow exhibited a helical movement, whereas the fluid near the sidewall had a stop-start movement pattern; the viscous debris flow exhibited a stable structure between the indented sills. The experimental results indicate that the mean velocity of the debris flow increased with increasing channel gradients, and the debris flow velocity was slightly affected by the angle of the sills. The average velocity of the non-viscous debris flow increased in the range of(0.5–1.5) interval between the indented sills, whereas the average velocity of the viscous debris flow increased initially and then decreased in the range of(0.75–1.25) interval between the indented sills. The depth of the non-viscous debris flow tended to gradually increase as the channel gradients increased, whereas the depth of the viscous debris flow gradually decreased as the channel gradients increased. When the discharge of the debris flow was constant, the angle and the interval between the indented sills had a slight effect on the depth of the viscous debris flow, whereas the depth of the non-viscous debris flow exhibited a different trend, as the sill angles and intervals were varied. 展开更多
关键词 Debris flow Drainage channel Staggered indented sill Wenchuan earthquake
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Bar in SILL Questionnaire for Multiple Results Processing: Users' Frequency and Confidence 被引量:1
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作者 Penelope Kambakis-Vougiouklis 《Sino-US English Teaching》 2013年第3期184-199,共16页
One hundred and fifteen first-year students of Greek took the SILL (Strategy Inventory for Language Learning) questionnaire in an attempt to reveal and activate potential a successful and widely used questionnaire l... One hundred and fifteen first-year students of Greek took the SILL (Strategy Inventory for Language Learning) questionnaire in an attempt to reveal and activate potential a successful and widely used questionnaire like SILL might have but not identified and investigated so far. The first original point to be investigated, tackled in a previous experiment (Kambakis-Vougiouklis, 2012), concerns users' confidence whether their choice of a specific strategy is effective while the second point concerns the use of the bar as an alternative statistical tool. More specifically, in this particular experiment the bar is not divided only into five equal length spaces as in the first experiment but also into five equal area spaces according to Gauss distribution, giving the researcher the chance to investigate possible differences between two ways of data processing--an advantage only the use of the bar could provide in the analysis stage. Additionally, there are advantages concerning results collection, as subjects and researcher will have a completely free choice among infinite points on a line rather than a limited 3, 4, 5, and 6 of a Likert scale, avoiding at the same time fine verbal differences between different subdivisions. Although the two different methods of processing performed homogeneous behaviour with not statistically considerable differences, it needs further applications in order to reach safe conclusions 展开更多
关键词 sill (Strategy Inventory for Language Learning) BAR CONFIDENCE Gauss distribution
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Geochemistry and petrology of rift-related mafic sills and arc-related Gabbro–Diorite bodies, Northern Bafq District,Central Iran
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作者 S.M.Niktabar N.Rashidnejad Omran 《Acta Geochimica》 EI CAS CSCD 2018年第2期180-192,共13页
Two types of mafic intrusions have been recognized in the north of the Bafq district, Central Iran. A number of olivine-gabbroic to gabbroic sills intruded the Rizu Formation, comprised of alternating carbonate and vo... Two types of mafic intrusions have been recognized in the north of the Bafq district, Central Iran. A number of olivine-gabbroic to gabbroic sills intruded the Rizu Formation, comprised of alternating carbonate and volcanic rocks. Mineralogical data show that olivine + pyroxene +brown amphibole(kaersutite) + calcic plagioclase +opaque comprise the olivine-gabbroic rocks, and intermediate(or sodic) plagioclase + altered pyroxene and altered amphibole to biotite + opaque minerals the gabbroic rocks.Both rock types have shown within-plate and alkaline characters and have been presumed to be related to rift formation. The mafic-alkaline magma source of the sills is proposed to have been derived from enriched mantle.Regionally, two Gabbro–Diorite intrusions have been identified in the metamorphic complexes. Mineralogical data suggest that the pyroxene + amphibole(hornblende) +plagioclase + biotite + opaque minerals formed the gabbro to diorite intrusions. These rocks have shown characteristics of calc-alkaline and volcanic arc magmatism. 展开更多
关键词 sillS Rizu formation RIFT Volcanic arc
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Refining the Stratigraphy of the Taghdout Group by Using the U-Pb Geochronology of the Taghdout Sill(Zenaga inlier,Anti-Atlas,Morocco)
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作者 Abdelhak AIT LAHNA Colombo Celso Gaeta TASSINARI +9 位作者 Nasrrddine YOUBI Hassan ADMOU Joao MATA El Hafid BOUOUGRI Latifa CHAIB Richard E.ERNST Ulf SODERLUND Moulay Ahmed BOUMEHDI Mohamed Khalil BENSALAH El Mostapha AARAB 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期1-,共1页
The Anti-Atlas belt of southern Morocco is situated on the northern edge of the West African craton(WAC).It corresponds to a broad anticlinorium some 800 km long and 200 km wide,trending ENE-WSW,parallel to the
关键词 Pb Zenaga inlier Morocco Refining the Stratigraphy of the Taghdout Group by Using the U-Pb Geochronology of the Taghdout sill ANTI-ATLAS
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Controlling entry in soft rock with natural support strength,strikesill,etc.
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作者 王有俊 赵庆彪 孙利中 《Journal of Coal Science & Engineering(China)》 2008年第2期186-189,共4页
Presented the concept of the natural support strength.The natural support strength,the strike sill,the multifunction retractors (developed by the author) and etc.were used with the technical measures to change the pas... Presented the concept of the natural support strength.The natural support strength,the strike sill,the multifunction retractors (developed by the author) and etc.were used with the technical measures to change the passive support to the initiative support, and the soft rock entry was supported.And its process is simple and less equipment is needed,and the cost is low and the advance rate is high,which can meet the require- ments of actual mining.It solves many support difficult problems. 展开更多
关键词 natural support strength strike sill multifunction retractor soft rock entry
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The Timing of the Palaeoproterozoic Great Oxidation Event using Dykes,Sills and Bolcanics of the Ongeluk Large Igneous Province,Kaapvaal Craton
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作者 Ashley P.GUMSLEY Kevin R.CHAMBERLAIN +5 位作者 Wouter BLEEKER Ulf SODERLUND Michiel O.DE KOCK Tobias C.KAMPMANN Emilie R.LARSSON Andrey BEKKER 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期67-68,共2页
The Neoarchaean to Palaeoproterozoic Transvaal Supergroup of the Kaapvaal Craton,southern Africa,is one of the best-preserved and most complete stratigraphic records across a critical in juncture in the Earth’s history.
关键词 sills and Bolcanics of the Ongeluk Large Igneous Province The Timing of the Palaeoproterozoic Great Oxidation Event using Dykes GOE
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从华北燕辽岩床群到哥伦比亚超大陆巨型裂谷系——燕辽大火成岩省近20年研究回顾与展望
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作者 张拴宏 赵越 +3 位作者 裴军令 杨振宇 胡国辉 张琪琪 《地质学报》 EI CAS CSCD 北大核心 2024年第3期783-798,共16页
近20年的研究工作表明,华北克拉通北部燕辽地区侵入到中元古代沉积地层中的大规模辉绿岩床群构成了一个1.32 Ga的基性大火成岩省。该大火成岩省与华北克拉通西北缘白云鄂博矿区富稀土-铌火成碳酸岩相伴生。大火成岩省、沉积地层对比和... 近20年的研究工作表明,华北克拉通北部燕辽地区侵入到中元古代沉积地层中的大规模辉绿岩床群构成了一个1.32 Ga的基性大火成岩省。该大火成岩省与华北克拉通西北缘白云鄂博矿区富稀土-铌火成碳酸岩相伴生。大火成岩省、沉积地层对比和古地磁资料研究结果表明,燕辽大火成岩省与北澳大利亚克拉通代理姆-加里温库大火成岩省是被大陆裂解分割开来的同一个基性大火成岩省的组成部分,显示1.8~1.3 Ga期间华北克拉通北-北东缘与北澳大利亚克拉通北缘在哥伦比亚(奴那)超大陆中长期相邻(连)。全球1.4~1.3 Ga大火成岩省及基性岩浆活动的时空分布及其岩石学、地球化学及同位素组成对比研究显示,这些全球广泛分布的大火成岩省或基性岩浆活动主要形成于裂谷环境。结合1.4 Ga左右哥伦比亚超大陆古地理重建结果,发现在哥伦比亚超大陆中存在沿劳伦(北美+格陵兰)克拉通西缘、西伯利亚克拉通西缘及北缘、波罗地克拉通东南缘、西非克拉通西缘及北缘、亚马逊克拉通西南缘、刚果/圣弗朗西斯科克拉通南缘及东缘、卡拉哈里克拉通东缘、华北克拉通北缘及北澳大利亚克拉通北缘分布,长度>15000 km的巨型裂谷系。该巨型裂谷系由一个主裂谷带和三个分支裂谷组成,其中主裂谷带和位于华北与北澳大利亚克拉通之间的分支裂谷发展成了大洋,并导致了大陆分离;而位于西伯利亚东缘、格陵兰北缘和波罗地东缘的1.38 Ga分支裂谷,以及位于北美北缘和西伯利亚西南缘的1.35~1.32 Ga分支裂谷则为夭折裂谷,未导致大陆裂离。这一巨型裂谷系是哥伦比亚超大陆裂解的重要标志,并可能是其最终裂解的最主要原因。另外,研究结果也显示,虽然全球两个最大规模的火成碳酸岩型稀土矿床,即华北克拉通西北缘的白云鄂博超大型稀土矿床和北美克拉通西缘的Mountain Pass超大型稀土矿床在哥伦比亚超大陆中并不相邻(相连),但却可以通过1.4~1.3 Ga巨型裂谷系相联系起来,显示这一巨型裂谷系控制了白云鄂博和Mountain Pass大型稀土矿床的形成,并具有较好的稀土及金属成矿潜力。未来需要进一步加强燕辽辉绿岩床群侵位机制与岩浆补给系统,岩床侵位过程中温室气体排放量定量估算及其环境效应,哥伦比亚超大陆中1.4~1.3 Ga巨型裂谷系的形成机制、深部动力学背景、环境效应及资源能源潜力等方面的研究。 展开更多
关键词 基性岩床群 大火成岩省 超大陆裂解 古地理重建 哥伦比亚超大陆 华北克拉通
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基于SILL的国内大学生学习策略与英语成绩相关的元分析 被引量:10
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作者 李文 张军 《外语教学理论与实践》 CSSCI 北大核心 2018年第4期39-47,共9页
本研究旨在探讨基于Oxford's (1990) Strategy Inventory for Language Learning (SILL)的国内大学生学习策略与英语成绩的相关,并探讨影响二者关系的研究特征的调节作用。通过文献检索,纳入文献41篇,产生48个独立研究样本,总样本量... 本研究旨在探讨基于Oxford's (1990) Strategy Inventory for Language Learning (SILL)的国内大学生学习策略与英语成绩的相关,并探讨影响二者关系的研究特征的调节作用。通过文献检索,纳入文献41篇,产生48个独立研究样本,总样本量为8689。结果表明,大学生学习策略与英语成绩呈从小到中等程度的显著正相关。记忆策略、情感策略与英语成绩的相关受被试类型、考核方式的调节作用;学习策略与英语成绩的相关不受出版类型的影响。 展开更多
关键词 英语学习策略 英语成绩 sill 元分析
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基于模型试验的齿坎型重力锚抗滑机制
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作者 吴文涛 李秋 +4 位作者 许健 韩洪举 宗昕 刘荣开 王成汤 《科学技术与工程》 北大核心 2024年第7期2927-2936,共10页
为了探究齿坎型重力式锚碇的承载特性与抗滑机制,依托贵州省牂牁江特大桥纳雍岸重力式锚碇工程,开展了相同试验条件下平底锚碇1/4埋深、齿坎锚碇1/4埋深、平底锚碇半埋深及齿坎锚碇半埋深四种工况的室内物理模型试验,并对各工况锚碇位移... 为了探究齿坎型重力式锚碇的承载特性与抗滑机制,依托贵州省牂牁江特大桥纳雍岸重力式锚碇工程,开展了相同试验条件下平底锚碇1/4埋深、齿坎锚碇1/4埋深、平底锚碇半埋深及齿坎锚碇半埋深四种工况的室内物理模型试验,并对各工况锚碇位移-荷载曲线、锚碇-地基接触应力、地基应变及地基宏观变形破坏特征进行分析。结果表明:四种工况锚碇模型的极限承载力分别为3P(平底1/4埋深)、4P(齿坎1/4埋深)、7P(平底半埋深)和8P(齿坎半埋深);同种型式锚碇模型增大埋深可以显著提升锚碇的承载能力,同等埋深条件下齿坎型重力式锚碇承载性能要优于平底重力式锚碇;齿坎构造能够充分调动地基联合承载;基于地基的宏观变形破坏特征将其变形破坏过程划分为无裂隙、裂隙初现、裂隙发展以及破坏四个阶段;对齿坎型重力式锚碇承力过程进行了力学分析,得出齿坎构造力学特性较好,对限制锚碇变位和提高锚碇承载能力作用明显。 展开更多
关键词 齿坎型重力锚 模型试验 承载特性 抗滑机制
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缓坡泄洪放空洞掺气坎水力特性试验分析
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作者 孙振兴 王芳芳 +3 位作者 孙晨光 冯业林 樊顾飞 吴时强 《水力发电学报》 CSCD 北大核心 2024年第2期57-66,共10页
高速水流掺气是减免流道空蚀破坏的有效措施,然而在缓底坡、大水位变幅条件下,常规掺气坎难以形成稳定无积水的掺气空腔。本文在缓底坡(3.3%)条件下,采用模型试验方法,对比分析了常规连续坎、异型坎及组合坎的水流特性和掺气效果,认为F... 高速水流掺气是减免流道空蚀破坏的有效措施,然而在缓底坡、大水位变幅条件下,常规掺气坎难以形成稳定无积水的掺气空腔。本文在缓底坡(3.3%)条件下,采用模型试验方法,对比分析了常规连续坎、异型坎及组合坎的水流特性和掺气效果,认为Fr数、掺气坎坡度与水舌落点处底板坡度是影响水流入射角的主要因素;在此底坡条件下,掺气坎尺寸变化的影响要远大于体型变化的影响,采用异型掺气坎亦难有效解决掺气空腔积水问题;经依托工程模型试验论证,组合坎掺气流态良好,适应大变幅的运行水头,可较好地改善缓底坡空腔回流积水问题。 展开更多
关键词 缓底坡 连续坎 异型坎 组合坎 回流积水
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牂牁江特大桥重力锚承载机制与稳定性研究
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作者 韩洪举 刘新华 +2 位作者 吴文涛 宗昕 王成汤 《地下空间与工程学报》 CSCD 北大核心 2024年第S01期316-323,349,共9页
依托牂牁江特大桥纳雍侧重力锚工程,采用FLAC3D三维数值模拟与理论分析相结合的研究方法,模拟了超载条件下锚碇-地基系统的力学响应,分析了锚碇变位、齿坎夹持岩体剪切承载特征、塑性区演化规律及系统的稳定性,揭示了重力锚结构-地基联... 依托牂牁江特大桥纳雍侧重力锚工程,采用FLAC3D三维数值模拟与理论分析相结合的研究方法,模拟了超载条件下锚碇-地基系统的力学响应,分析了锚碇变位、齿坎夹持岩体剪切承载特征、塑性区演化规律及系统的稳定性,揭示了重力锚结构-地基联合承载机制。结果表明:纳雍侧重力锚的极限承载力为6P;锚碇在缆力荷载作用下发生变位,进而通过基底摩擦及齿坎夹持效应调动周围地基岩体共同承载,且调动岩体承载的顺序为从基底向上逐级调动各级齿坎,齿坎夹持部分的岩体则是通过抗剪作用提供被动抗力;理论分析和数值模拟结果均表明,同时考虑摩擦和齿坎夹持效应时,工程设计缆力荷载作用下锚碇-地基系统的稳定性系数可达6.0以上,远大于仅考虑摩擦效应时的稳定性系数。 展开更多
关键词 桥梁工程 联合承载机制 数值重力锚-地基系统 齿坎效应 稳定性分析
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