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植物增产剂“施施乐”(CCR)对冬小麦的增产效果 被引量:4
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作者 宁书菊 魏道智 《广西农业生物科学》 CSCD 1999年第2期163-163,共1页
“施施乐”(CCR)是由氯化胆碱(CC)和增效剂配制而成的一种植物增产增糖剂。试验表明,其增产增糖效果比单独使用CC者更好。曾在南方地区多种作物上叶面喷施,增产效果显著。本文报道CCR用于北方麦区,同样获得明显的增产... “施施乐”(CCR)是由氯化胆碱(CC)和增效剂配制而成的一种植物增产增糖剂。试验表明,其增产增糖效果比单独使用CC者更好。曾在南方地区多种作物上叶面喷施,增产效果显著。本文报道CCR用于北方麦区,同样获得明显的增产效果。供试材料为冬小麦(Triti... 展开更多
关键词 冬小麦 植物增产剂 施施 增产
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芦柑喷施施必恩效果明显
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作者 姚建族 《福建农业科技》 1999年第S1期198-199,共2页
关键词 喷施宝 芦柑 叶面喷施 定位试验 施施 有效微量元素含量 观察记载 经济效益分析 畸形花 增产效果
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Water and Fertilizer Coupling Model for the Yield of Greenhouse Eggplant in Winter Cropped in Ningxia Southern Mountain Region 被引量:2
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作者 刘根红 李建设 《Agricultural Science & Technology》 CAS 2010年第2期109-112,共4页
[Objective] The research aimed to study the coupling model of water and fertilizer for the yield of winter eggplant in greenhouse in Ningxia southern mountain region and provide reference for the criteria and cost-sav... [Objective] The research aimed to study the coupling model of water and fertilizer for the yield of winter eggplant in greenhouse in Ningxia southern mountain region and provide reference for the criteria and cost-saving cultivation of agriculture vegetables in Ningxia southern mountain region.[Method] By using quadratic general rotary unitized design,the mathematics simulation was made on the main cultivation factors(irrigated amount,N application amount,K application amount)that affected the greenhouse eg... 展开更多
关键词 EGGPLANT Irrigation amount N application amount K application amount
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Effects of Nitrogen Application Amount during Various Periods on Yield of High Grade Hybrid Rapeseed 被引量:1
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作者 赵继献 任廷波 程国平 《Agricultural Science & Technology》 CAS 2012年第6期1292-1297,共6页
[Objective] The paper was to study the nitrogen application amount and nitrogen application model for high grade hybrid rapeseed (Brassica napus L.) to get high yield. [Method] With "Youyan 599" and "Sanbei 98" ... [Objective] The paper was to study the nitrogen application amount and nitrogen application model for high grade hybrid rapeseed (Brassica napus L.) to get high yield. [Method] With "Youyan 599" and "Sanbei 98" as materials, using quadratic regression orthogonal gyration combination design, the impact of nitrogen application amount during various periods on rapeseed yield was studied. [Result] The combinations of factors to obtain the highest yield index (2 898.211 kg / hm 2 ) of "Youyan 599" were as follows: living rape fertilizer 89.27 kg / hm 2 , opening fertilizer 120 kg / hm 2 , 12 th lunar month fertilizer 101.12 kg / hm 2 , total nitrogen application amount 310.39 kg / hm 2 . The proportions of living rape fertilizer, opening fertilizer and 12th lunar month fertilizer were 28.76%, 38.66% and 32.58%, respectively. The combinations of factors to obtain the highest yield index (2 870.14 kg/hm 2 ) of "Sanbei 98" were as follows: living rape fertilizer 120 kg / hm 2 , opening fertilizer 120 kg / hm 2 , 12 th lunar month fertilizer 37.55kg / hm 2 , total nitrogen application amount 277.55 kg / hm 2 . The proportions of living rape fertilizer, opening fertilizer and 12 th lunar month fertilizer were 43.24%, 43.24% and 13.53%, respectively. The combinations of factors to obtain the highest yield index of two combined varieties (2 813.82 kg/hm 2 )were as follows: living rape fertilizer 120 kg/hm 2 , opening fertilizer 120 kg/hm 2 , 12 th lunar month fertilizer 76.23 kg/hm 2 , total nitrogen application amount 316.23 kg/hm 2 . The proportions of living rape fertilizer, opening fertilizer and 12 th lunar month fertilizer were 37.95% , 37.95% and 24.11% , respectively. [Conclusion] The paper provided theoretical basis for high yield cultivation of high grade hybridized rapeseed. 展开更多
关键词 Hybrid rapeseed Application period of nitrogen fertilizer Application amount of nitrogen PROPORTION
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Effect Models of Nitrogen,Phosphorus and Potassium Fertilizer Formulation in Banana 被引量:1
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作者 匡石滋 田世尧 +3 位作者 李春雨 易干军 洪炎龙 万国富 《Agricultural Science & Technology》 CAS 2010年第9期130-135,共6页
[Objective] The aim was to modify the application amount of N,P and K fertilizer so as to provide a reference for establishing balanced fertilization index system of banana.[Method]The N,P and K fertilizer "3414" te... [Objective] The aim was to modify the application amount of N,P and K fertilizer so as to provide a reference for establishing balanced fertilization index system of banana.[Method]The N,P and K fertilizer "3414" test was carried out on banana,and then regression analysis was performed on the fertilizer effect.Ternary quadratic,binary quadric and one-variable quadratic regression equations for the fertilizer effect on the banana yield were constructed.[Result]Suitable amount of N,P and K fertilizer had significant yield improving effect,whereas overdose of fertilizer application led to decreasing of utilization rate of fertilizer.Therefore,suitable amount of N,P and K fertilizer should be selected in production.It could be concluded that one-variable quadratic regression equations was the best model to calculate the suitable fertilizer amount.The best yield range of banana in the tested field was 44.193-45.904 t/hm2,while the corresponding optimum application amount of N,P2O5 and K2O was 795.1,262.3 and 1 236.9 kg/hm2 respectively,and the ratio among nitrogen,phosphorus and potassium are 1∶0.33∶1.55.[Conclusion]The result in this study could provide references for the soil types similar to the tested field. 展开更多
关键词 BANANA NITROGEN Phosphorus and potassium fertilization Fertilizer application model Optimum application amount
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Establishment of a Mathematical Model for Mulberry Balanced Fertilization in Hilly Areas of Sichuan Province
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作者 刘刚 帅小蓉 +7 位作者 张建华 殷浩 佟万红 罗春燕 黄盖群 林超文 危玲 夏庆友 《Agricultural Science & Technology》 CAS 2012年第10期2137-2141,2146,共6页
In order to increase mulberry leaf yield and production efficiency in hilly areas of Sichuan Province through scientific fertilization,"3414",a quadratic regression design for modern fertilization,was employed to si... In order to increase mulberry leaf yield and production efficiency in hilly areas of Sichuan Province through scientific fertilization,"3414",a quadratic regression design for modern fertilization,was employed to simulate the regression relationship between mulberry leaf yield and major fertilizer elements including nitrogen(N),phosphor(P) and potassium(K) among which mulberry leaf yield was the objective function and N,P and K were the regulatory factors to fertilization level.As a result,7 types of ternary,binary and monadic quadratic fertilizer effect functions of N,P and K fertilizer elements were established.The weight of fertilizer factors in the optimal mulberry leaf yield obtained by various types of functions was in decreasing order of KPKPNPKNKNNP,and the weight of fertilizer factors in the ratio of leaf yield to input was in decreasing order of K〉PK〉NPK〉P〉NK〉NP〉N.To be specific,the ternary quadratic fertilizer effect function(Y=20 313+0.25X1+43.48 X2+34.47X3-0.01X1^2-0.14X2^2-0.06X3^2+0.05X1X2+0.02X1X3-0.07X2X3,in which X1,X2 and X3 indicate the fertilizer factors N,P and K,respectively) was a model containing all factors,thereby being a recommended fertilization program for mulberry field.Single factor effect analysis indicated that K fertilizer had the highest influence on mulberry leaf yield and ratio of leaf yield to input.Therefore,among all the simulation functions,the monadic quadratic fertilizer effect function of K fertilizer factor(Y=25 002.27+44.728X3-0.084X32) leads to the optimal leaf yield and maximum ratio of leaf yield to input.By using the optimal fertilization program with 600 kg/hm2 N,210 kg/hm2 P2O5 and 254.33 kg/hm2 K2O,the optimal economic leaf yield obtained is 30 945.00 kg/hm2,the cost of fertilizer input is 4 403.65 yuan/hm2,and the ratio of leaf yield to input is as high as 17.57.After verification by production practices,the recommended fertilization indicators in the optimal mulberry fertilization program can provide reference for the construction of high-yield mulberry field in hilly areas of Sichuan Province. 展开更多
关键词 MULBERRY High yield Balanced fertilization Fertilizer effect function
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走近宫鲁鸣——国家男篮探营
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作者 雷越姝 《中国体育科技》 北大核心 1996年第10期27-27,共1页
体委训练局是个藏龙卧虎的地方。你会冷不丁看见伏明霞从前面的马路上施施然而去,或者没等你反应过来,一个剃小平头的小伙子飞车而过,哦,那是小个子大力士占旭刚。 所以当我到羽排球馆找宫鲁鸣时,看见两个高大小伙子一个逃一个追地从馆... 体委训练局是个藏龙卧虎的地方。你会冷不丁看见伏明霞从前面的马路上施施然而去,或者没等你反应过来,一个剃小平头的小伙子飞车而过,哦,那是小个子大力士占旭刚。 所以当我到羽排球馆找宫鲁鸣时,看见两个高大小伙子一个逃一个追地从馆内枉奔而出,我立马就认清楚了,那是王治郅和吴庆龙。篮球馆正在装修,男篮暂时借用了羽排馆的场地。队长吴庆龙不知什么事惹恼了王冶郅,逃得狼狈之极,王治郅横抓着一个拖把,追得勇猛无比。宫鲁鸣解释说:男篮在奥运之前训练特别紧张。 展开更多
关键词 男篮 王治 小伙子 队长 主力队员 奥运会 小平头 施施 大力士 小个子
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反训即反义同词吗?
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作者 李万福 《四川师范大学学报(社会科学版)》 1987年第1期59-63,70,共6页
近来谈反训的文章称反训即反义同词。“反训”是训诂学术语,训诂学与文字学,音韵学构成传统的小学。“反义同词”是基于现代语言学的新提法。既然小学不同于语言学、训诂学不同于语义学,术语对科学体系的依存性告诉我们,反训也很难与反... 近来谈反训的文章称反训即反义同词。“反训”是训诂学术语,训诂学与文字学,音韵学构成传统的小学。“反义同词”是基于现代语言学的新提法。既然小学不同于语言学、训诂学不同于语义学,术语对科学体系的依存性告诉我们,反训也很难与反义同词完全一致。 展开更多
关键词 反训 反义同词 训释 方言词 共名 词义 指号 钱绎 施施 透义性
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“扮官”的戏精何以能屡屡成功
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《协商论坛》 2017年第12期56-56,共1页
8月底,福建省直机关工委官网发布消息,称'‘林智双’不是省直机关工委干部,有关其人的新闻报道均为不实信息'。之前多年,林智双成功地扮演了官员和媒体人,不仅介入具体事件,帮人'疏通关系',还现身各大场合,秀出多张与... 8月底,福建省直机关工委官网发布消息,称'‘林智双’不是省直机关工委干部,有关其人的新闻报道均为不实信息'。之前多年,林智双成功地扮演了官员和媒体人,不仅介入具体事件,帮人'疏通关系',还现身各大场合,秀出多张与省级、厅级领导合照,且以媒体人身份署名的不少稿件,都刊发于某网站舆情频道。 展开更多
关键词 省直机关工委 新闻报道 林智 频道 秀出 网站 帮人 现身 社会环境 施施
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油菜虫害分析与防治对策
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作者 胡伶俐 《湖北教育(科学课)》 1999年第12期30-30,共1页
我们家乡的冬季农作物,除了少量的小麦外,大部分都是移栽和点播的油菜。这是农民次年春耕生产购买种子、农药、肥料的主要经济来源。由于蚜虫、小菜蛾、菜青虫等对油菜的危害猖獗,无论是移栽的甘蓝型油菜,还是点播的白菜型油菜。
关键词 分析与防治 油菜 寄生虫害 施施 喷九 叶汁 春耕生产 小菜蛾 菜青虫 久效磷
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《始得西山宴游记》阅读训练
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作者 熊芳芳 《语文世界(中旬刊)》 2003年第10期46-13,共2页
自余为僇人,居是州,恒惴栗。其隙也,则施施而行,漫漫而游。日与其徒上高山,入深林,穷回溪,幽泉怪石,无远不到。到则披草而坐,倾壶而醉。醉则更相枕以卧。卧而梦,意有所极,梦亦同趣。觉而起,起而归。
关键词 《始得西山宴游记》 词类活用 人生志趣 阅读训练 特立 景物 词意 永州 不同之处 施施
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说“舍施”
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作者 林华东 《闽台文化研究》 2022年第2期44-49,共6页
闽南方言是古汉语的“活化石”,传承了古代汉语的许多语言特征。闽南方言随着闽南人的脚步走出福建,走向台湾地区,走向世界,成为跨省域、跨国界的汉语方言。生活在海外的闽南人特别珍惜闽南方言的保护,把它作为守望中华文化的象征;他们... 闽南方言是古汉语的“活化石”,传承了古代汉语的许多语言特征。闽南方言随着闽南人的脚步走出福建,走向台湾地区,走向世界,成为跨省域、跨国界的汉语方言。生活在海外的闽南人特别珍惜闽南方言的保护,把它作为守望中华文化的象征;他们不仅是口口相传,还注重书写记录,不时思索历史本原。新加坡华人口语中的“舍施”和“无舍施”,以及“丈夫”等词语,都源于古代汉语,体现了闽南方言的悠久和海内外闽南人共同对古代汉语的守护。闽南方言是联系海上丝绸之路沿线国家闽南华侨华人的重要纽带。 展开更多
关键词 舍施 无舍施 丈夫 古代汉语 闽南方言 泉州
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省消防总队对建筑消设施“回炉”治理追根溯源制定“治本”之策
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作者 倪国红 《安徽消防》 1997年第11期9-9,共1页
近日,省消防总队根据对建筑消防设施“复查”暴露出的问题,及时制定了进一步加强监督管理工作的措施,促进了今年以来开展的将建筑消防设施“回炉”治理的工作。 去年5月是公安部等国家五部局确定的“全国建筑消防设施专项治理宣传月”。
关键词 建筑消防 消防总队 追根溯源 维护管理 消防设施 施施 消防技术规范 及时制 消防监督机构 防火设计
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Scheme of Nitrogen Reasonable Fertilization in Mulberry Gardens of Sichuan Hilly Areas
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作者 殷浩 张建华 +5 位作者 佟万红 刘刚 黄盖群 危玲 罗春燕 王丽 《Agricultural Science & Technology》 CAS 2012年第9期1933-1936,共4页
Abstract In the research, five test groups were set, including urea at O, 120, 240, 360 and 480 kg/hm^2, respectively, and analysis was conducted on mulberry leaf yield and some characters of the quality in order to e... Abstract In the research, five test groups were set, including urea at O, 120, 240, 360 and 480 kg/hm^2, respectively, and analysis was conducted on mulberry leaf yield and some characters of the quality in order to establish utility functions of ap-plied N in mulberry gardens with different production purposes and to provide schemes of rational N fertilization. The results indicated that yield of mulberry leaf and content and yield of active nutritional substances in the leaves would be reduced either by insufficient or excessive N quantity. In addition, 240 kg/hm^2 of applied N significantly improved active nutritional substances in leaf and 360 kg/hm^2 of applied N significantly improved yields of mulberry leaf and active nutritional sub-stances. Therefore, utility functions of applied N quantity with leaf yield, DNJ content and yield were established accordingly. The optimal N quantity in mulberry gardens for sericulture is recommended 360 kg/hm^2 and the optimal N quantities in mulberry gardens for increase of yield and content of DNJ are 299.56 and 294.72 kg/hm^2, respectively. 展开更多
关键词 Mulberry tree N quantity Yield of mulberry leaf Nutritional active sub-stances 1-DEOXYNOJIRIMYCIN
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Effect of Different Fertilization Methods on Grain Yield and Nitrogen Agronomy Efficiency of TwoLine Super Hybrid Rice 被引量:1
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作者 何爱斌 刘科 +3 位作者 孙志贵 龙继锐 田小海 张运波 《Agricultural Science & Technology》 CAS 2014年第10期1723-1726,共4页
ln order to explore the effect of broadcast application of urea (BR-U) and surface concentrated-fertilization on grain yield and nitrogen agronomy efficiency of two-line super hybrid rice, this experiment was conduc... ln order to explore the effect of broadcast application of urea (BR-U) and surface concentrated-fertilization on grain yield and nitrogen agronomy efficiency of two-line super hybrid rice, this experiment was conducted with super hybrid rice Y-Liangyou 1 and Liangyou 0293 to determine til ering dynamics, SPAD, LAl and dry matter accumulation. lts total N application was 180 kg/hm2 and different application rate and topdressing methods were set respectively. The results showed that grain yield and nitrogen agronomy efficiency were significantly improved with the T3 and T4 nitrogenous fertilizer application model. The improving of grain yield and nitrogen agronomy efficiency was benefited from rational postponing N application. However, neither single application of base fertilizer (T2) nor single application of topdressing fertilizer (T5 and T6) can coordinate the relationship between source and sink. Both grain yield and nitrogen agronomy efficiency were insignificantly under the broadcast application of urea and surface concentrated fertilization. 展开更多
关键词 Two-line super hybrid rice Broadcast application Concentrated-fertilization YIELD Nitrogen agronomy efficiency
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STUDY ON INDEX SYSTEM OF ASSESSMENT OF PUBLIC DISASTER PERCEPTION IN THE WESTERN CHINA 被引量:19
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作者 ZHOUOi LIJing-yi ZHAOJing-bo 《Chinese Geographical Science》 SCIE CSCD 2003年第3期284-288,共5页
The study on humanity response to global environment change is a new direction in the research of global change science, of which an important aspect is to study the adaptation strategies of human being to environment... The study on humanity response to global environment change is a new direction in the research of global change science, of which an important aspect is to study the adaptation strategies of human being to environmental changes in different regions. One reasonable and scientific adaptation strategy is based on not only scientific assessment of the impact of environmental change on society, but also correct estimation of the public perception of environmental change, whereas the research on the latter is terribly weak. This paper intends to understand the personality difference in public perception of environment in the western China primarily by establishing the assessment index system of nation environmental perception and analyzing the results of questionnaire survey in some regions of Shaanxi Province. The conclusions are as follows: 1) The state of public perception of disaster is one of the foundations of constituting and enforcing reasonable adaptation strategy to environmental change. 2) The personality differences of public perception of disaster appear as follows: female disaster perception is stronger than male;the order of disaster perception from strong to weak from the point of age characteristics is 20-30, 0-20, 40-50, 30-40, 50-60, 60 year old or over in turns; the order of disaster perception from strong to weak from the point of educational characteristics is senior high school, college, illiterate, junior high school, primary school, in turns; the order of disaster perception from strong to weak from the point of occupation characteristics is student, farmer, teacher, worker and functionary, in turns; the order of disaster perception from strong to weak from the point of habitat characteristics is city, countryside, towns, and metropolis in turns. 展开更多
关键词 global change disaster perception disaster reduction strategy western China
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Forms and Aesthetics of Bridges 被引量:14
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作者 Man-Chung Tang 《Engineering》 2018年第2期103-112,共10页
The objective of a bridge design is to produce a safe bridge that is elegant and satisfies all functionality requirements, at a cost that is acceptable to the owner. A successful bridge design must be natural, simple,... The objective of a bridge design is to produce a safe bridge that is elegant and satisfies all functionality requirements, at a cost that is acceptable to the owner. A successful bridge design must be natural, simple, original, and harmonious with its surroundings. Aesthetics is not an additional consideration in the design of a bridge, but is rather an integral part of bridge design. Both the structural configuration and the aesthetics of a bridge must be considered together during the conceptual design stage. To achieve such a task, the bridge design engineer must have a good understanding of structural theory and bridge aesthetics. 展开更多
关键词 FORM AESTHETICS BRIDGE Concept Design Environment
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Impact of Low-Impact Development Technologies from an Ecological Perspective in Different Residential Zones of the City of Atlanta, Georgia 被引量:2
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作者 Zackery B. Morris Stephen M. Malone +2 位作者 Abigail R. Cohen Marc J. Weissburg Bert Bras 《Engineering》 2018年第2期30-35,共6页
Low-impact development (LID) technologies have a great potential to reduce water usage and stormwa- ter runoff and are therefore seen as sustainable improvements that can be made to traditional water infrastructure,... Low-impact development (LID) technologies have a great potential to reduce water usage and stormwa- ter runoff and are therefore seen as sustainable improvements that can be made to traditional water infrastructure, These technologies include bioretention areas, rainwater capturing, and xeriscaping, all of which can be used in residential zones, Within the City of Atlanta, residential water usage accounts for 53% of the total water consumption; therefore, residential zones offer significant impact potential for the implementation of LID, This study analyzes the use of LID strategies within the different residen- tial zones of the City of Atlanta from an ecological perspective by drawing analogies to natural ecosys- tems, The analysis shows that these technologies, especially with the addition of a graywater system, work to improve the conventional residential water network based upon these ecological metrics, The higher metric values suggest greater parity with healthy, natural ecosystems. 展开更多
关键词 Low-impact development Ecological network analysis Residential water consumption
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The Ceneri Base Tunnel" Construction Experience with the Southern Portion of the Flat Railway Line Crossing the Swiss Alps 被引量:11
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作者 Davide Merlini Daniele Stocker +1 位作者 Matteo Falanesca Roberto Schuerch 《Engineering》 2018年第2期71-84,共14页
This paper summarizes the experience that was gained during the construction of the 15.4 km long Ceneri Base Tunnel (CBT), which is the southern part of the fiat railway line crossing the Swiss Alps from north to so... This paper summarizes the experience that was gained during the construction of the 15.4 km long Ceneri Base Tunnel (CBT), which is the southern part of the fiat railway line crossing the Swiss Alps from north to south. The project consisted of a twin tube with a diameter of 9 m interconnected by cross- passages, each 325 m long. In the middle of the alignment and at its southern end, large caverns were excavated for logistical and operational requirements. The total excavation length amounted to approx- imately 40 km. The tunnel crossed Alpine rock formations comprising a variety of rock typologies and several fault zones. The maximum overburden amounted to 850 m. The excavation of the main tunnels and of the cross-passages was executed by means of drill-and-blast (D&B) excavation. The support con- sisted of bolts, meshes, fiber-reinforced shotcrete and, when required, steel ribs. A gripper tunnel boring machine (TBM) was used in order to excavate the access tunnel. The high overburden caused squeezing rock conditions, which are characterized by large anisotropic convergences when crossing weaker rock formations. The latter required the installation of a deformable support. At the north portal, the tunnel (with an enlarged cross-section) passed underneath the A2 Swiss highway (the major road axis connect- ing the north and south of Switzerland) at a small overburden and through soft ground. Vertical and sub- horizontal jet grouting in combination with partial-face excavation was successfully implemented in order to limit the surface settlements. The south portal was located in a dense urban area. The excavation from the south portal included an approximately 220 m long cut-and-cover tunnel, followed by about 300 m of D&B excavation in a bad rock formation. The very low overburden, poor rock quality, and demanding crossing with an existing road tunnel (at a vertical distance of only 4 m) required special excavation methods through reduced sectors and special blasting techniques in order to limit the blast-induced vibrations. The application of a comprehensive risk management procedure, the execution of an intensive surface survey, and the adaptability of the tunnel design to the encountered geological conditions allowed the successful completion of the excavation works. 展开更多
关键词 Deep and long tunnel Difficult ground conditions Support design Risk management Tunnel monitoring Large cavernsLow overburdenOverpass tunnel Numerical analysis Excavation in urban area
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Key Techniques for the Construction of High-Speed Railway Large-Section Loess Tunnels 被引量:9
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作者 Yong Zhao Huawu He Pengfei Li 《Engineering》 2018年第2期90-95,共6页
The successful completion of the Zhengzhou-Xi'an high-speed railway project has greatly improved the construction level of China's large-section loess tunnels, and has resulted in significant progress being made in ... The successful completion of the Zhengzhou-Xi'an high-speed railway project has greatly improved the construction level of China's large-section loess tunnels, and has resulted in significant progress being made in both design theory and construction technology. This paper systematically summarizes the tech- nical characteristics and main problems of the large-section loess tunnels on China's high-speed railway, including classification of the surrounding rock, design of the supporting structure, surface settlement and cracking control, and safe and rapid construction methods. On this basis, the key construction tech- niques of loess tunnels with large sections for high-speed railway are expounded from the aspects of design and construction. The research results show that the classification of loess strata surrounding large tunnels should be based on the geological age of the loess, and be determined by combining the plastic index and the water content. In addition, the influence of the buried depth should be considered. During tunnel excavation disturbance, if the tensile stress exceeds the soil tensile or shear strength, the surface part of the sliding trend plane can be damaged, and visible cracks can form. The pressure of the surrounding rock of a large-section loess tunnel should be calculated according to the buried depth, using the corresponding formula. A three-bench seven-step excavation method of construction was used as the core technology system to ensure the safe and rapid construction of a large-section loess tunnel, following a field test to optimize the construction parameters and determine the engineering measures to stabilize the tunnel face. The conclusions and methods presented here are of great significance in revealing the strata and supporting mechanics of large-section loess tunnels, and in optimizing the supporting structure design and the technical parameters for construction. 展开更多
关键词 Loess tunnel Surrounding rock classification Surface cracking Design load Three-bench seven-step excavation method
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