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Construction scheme comparison with comprehensive evaluation of independent perspectives
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作者 阎西康 王磊 CHEN Pei 《Journal of Chongqing University》 CAS 2013年第3期131-135,共5页
Considering both the characteristics of construction scheme evaluation and the lack of consideration of index proportionality after introducing comprehensive evaluation of independent perspectives into construction sc... Considering both the characteristics of construction scheme evaluation and the lack of consideration of index proportionality after introducing comprehensive evaluation of independent perspectives into construction scheme evaluation, a construction scheme evaluation model of independent perspectives was put forward through the study and optimization of comprehensive evaluation of independent perspectives. The feasibility and rationality of the optimized method were illustrated through a case study and the evaluation results were compared between the optimized method and non-optimized method. The optimized method has the practical value in construction scheme comparison. 展开更多
关键词 construction scheme evaluation model independent perspective comprehensive evaluation
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Study on Potential Problems of Shandong Economic Forest Construction and Standardization Construction Scheme
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作者 Runze CAO 《Asian Agricultural Research》 2013年第11期101-102,共2页
Shandong is a culturally powerful province with excellent natural geographical condition and the warm temperate monsoon climate creates abundant benefits to the agricultural development there.In 2009,Shandong administ... Shandong is a culturally powerful province with excellent natural geographical condition and the warm temperate monsoon climate creates abundant benefits to the agricultural development there.In 2009,Shandong administration bureau of Yellow River economic development held the forum on related issues of national new countryside industry office planning to build economic forest base around the Yellow River in Shandong.The primary intention was settled and the construction of Shandong Economic Forest was formally started.Although impressive progress has been achieved in recent years,there also exists potential problems in the construction of economic forest,among which heavy metal pollution and soil acidification are the worst,causing huge damage to the physiological health of the consumers of economic forest.The writer proposes the countermeasures against standardization construction of economic forest.Scientific management is to be adopted to improve the professional skills of the employees in economic forest and brand innovation should be emphasized to quicken the quality certification of the products of economic forest.Besides,standard production demonstration is to be created and promoted in order to boost scale development.Furthermore,mechanism innovation is also to be stressed and forestry specialized cooperation organizations should be largely supported. 展开更多
关键词 ECONOMIC FOREST Potential PROBLEMS COUNTERMEASURES
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Study on Effect of UHV Power Grid Construction Schemes on Short Circuit Current
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作者 Zaihua Li Feng Gao +3 位作者 Qing Wang Shuang Zhang Hongmei Luo Jian Liang 《Journal of Power and Energy Engineering》 2015年第4期200-205,共6页
The commissioning of Southern Hami-Zhengzhou ±800 kV UHVDC transmission project has important significance to heighten operation reliability, transfer capability and supply electric ability of Henan power grid. H... The commissioning of Southern Hami-Zhengzhou ±800 kV UHVDC transmission project has important significance to heighten operation reliability, transfer capability and supply electric ability of Henan power grid. However, short circuit currents of 500 kV buses in the Center of Henan are almost close to the operation upper limitation. In order to decrease the short circuit currents effectively, it’s necessary to strengthen the network structure of Center of Henan power grid and calculate short circuit currents. Two schemes of strengthening the network structure of Center of Henan power grid are studied. The calculated values of short circuit currents of some important 500 kV buses in the two schemes are still bigger than excepted. According to the latest Plan of State Grid, Yubei UHV substation and Zhumadian UHV substation located in Henan power grid. The calculated values of short circuit currents of some important 500 kV buses with the commissioning of Yubei UHV and Zhumadian UHV are qualified. So, reasonable network structure with UHV is suitable to heighten transfer capability and supply electric ability of Henan power grid. 展开更多
关键词 UHV UHVDC construction scheme SHORT CIRCUIT CURRENT
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REMARKS ON BOUNDS ON THE DISCREPANCY OF APPROXIMATE SOLUTIONS CONSTRUCTED BY GODUNOV'S SCHEME
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作者 王靖华 《Acta Mathematica Scientia》 SCIE CSCD 1989年第4期437-452,共16页
The bounds on the discrepancy of approximate solutions constructed by Gedunov's scheme to IVP of isentropic equations of gas dynamics are obtained, Three well-knowu results obtained by Lax for shock waves with sma... The bounds on the discrepancy of approximate solutions constructed by Gedunov's scheme to IVP of isentropic equations of gas dynamics are obtained, Three well-knowu results obtained by Lax for shock waves with small jumps for general quasilinear hyperbolic systems of conservation laws are extended to shock waves for isentropic equations of gas dynamics in a bounded invariant region with ρ=0 as one of boundries of the region. Two counterexamples are given to show that two iuequalities given by Godunov do not hold for all rational numbers γ∈(1, 3]. It seems that the approach by Godunov to obtain the forementioned bounds may not be possible. 展开更多
关键词 TE REMARKS ON BOUNDS ON THE DISCREPANCY OF APPROXIMATE SOLUTIONS constructED BY GODUNOV’S scheme
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Construction Vectors for Visual Cryptographic Schemes
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作者 FEI Ruchun 《Wuhan University Journal of Natural Sciences》 CAS 2014年第5期441-448,共8页
The concept of group construction vector and independent construction vector for visual cryptography is proposed, and the method based on construction vector is presented for con-structing basis matrices. The general ... The concept of group construction vector and independent construction vector for visual cryptography is proposed, and the method based on construction vector is presented for con-structing basis matrices. The general solutions to construction vectors and the general solutions to k out of n visual cryptographic schemes are obtained. Using the construction vectors, everyone can construct visual cryptographic schemes simply and efficaciously according to the formulas. The concept and the general solutions to construction vector present a good idea for researches on visual cryptographic schemes, including structural properties, the bound of pixel expansion and contrast, and optimal construction. 展开更多
关键词 visual cryptographic scheme basis matrix groupconstruction vector independent construction vector
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Study on the Construction of "Near Nature" Waterfront Greening Landscape
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作者 张文杰 屈培源 张文博 《Journal of Landscape Research》 2009年第4期1-6,24,共7页
The construction of 'Near Nature' waterfront greening landscape is a kind of waterfront construction model that complies with the nature and balances ecological landscape and regional development, which is of ... The construction of 'Near Nature' waterfront greening landscape is a kind of waterfront construction model that complies with the nature and balances ecological landscape and regional development, which is of great significance to restore the healthy waterfront ecosystem and sustainable development. Starting from the conception and characteristics of 'Near Nature' waterfront greening areas, the design principles and construction schemes of waterfront greening landscape such as river, lake, canal and wetland were studied. 展开更多
关键词 NEAR NATURE WATERFRONT GREENING LANDSCAPE constructION scheme
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Accuracy of Low-level Surface in Hierarchical Construction of Potential Energy Surface
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作者 Chun-rui Wang Dong H.Zhang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2012年第2期186-190,I0003,共6页
The effects of low-level PES on the overall accuracy of the final surface constructed by using hierarchical construction were investigated with the constructions of a number of global surfaces for the H3 system at UHF... The effects of low-level PES on the overall accuracy of the final surface constructed by using hierarchical construction were investigated with the constructions of a number of global surfaces for the H3 system at UHF (UMP2, DFT-B3LYP, UCCSD(T))/vtz, and UCCSD(T)/avqz levels of theory. The total reaction probabilities for the H+H2 reaction calculated on these surfaces revealed that the accuracy of UCCSD(T)/avqz surface is very close to the well-known BKMP2 surface, while the UCCSD(T)/vtz PES has a slightly higher barrier. In contrast, the low-level theories (UHF, UMP2, DFT-B3LYP) with vtz basis set can only provide a qualitative description of this simplest reaction despite the fact that they are widely used to study reactions in complex systems. On the other hand, although these theories are not accurate on describing the reaction, they can be used to provide the low- level PESs for hierarchical construction of the UCCSD(T)/avqz PES with the number of UCCSD(T)/avqz energies substantially reduced. 展开更多
关键词 Hierarchical construction scheme Accuracy of potential energy surface Three- dimensional cubic spline
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Finite Element Comparative Analysis on Construction Process of Long-span Steel Structure
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作者 WANGYing ZHANGXu ZHANGCheng 《外文科技期刊数据库(文摘版)工程技术》 2022年第3期136-141,共6页
There are various construction methods of long-span steel structure. In this paper, sap2000 is used to analyze the overall lifting technology of a 72*144m long-span steel structure. The grid structure is divided into ... There are various construction methods of long-span steel structure. In this paper, sap2000 is used to analyze the overall lifting technology of a 72*144m long-span steel structure. The grid structure is divided into two areas for lifting, and there are four different areas for different repair welding areas and lifting methods. By analyzing the indexes of stress, deformation and internal force of structure construction under different construction zoning schemes, the best construction scheme can be selected. The calculation results show that the construction deformation of the second scheme is the smallest, with the final deformation of 49.164mm, the maximum stress ratio of the components after construction being 0.204, and the stress ratio of the components under the load of 1.3D+1.5L being 0.8098, which is basically the same as the stress ratio of 0.80 obtained by the one-time loading design, so the second scheme is finally selected. 展开更多
关键词 large span grid structure finite element analysis different construction schemes
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单轨交通综合运营调度系统建设方案研究
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作者 刘涛 杨超 陈光 《都市快轨交通》 北大核心 2025年第1期83-89,98,共8页
针对数据管控和综合智能运维的需要,对中心、车站、车辆段/停车场系统设备从架构上进行整合设计,对各子系统进行集成或接口互联,在统一的平台上对各专业系统设备进行监视和控制。通过分析,采用综合运营调度的单轨系统可大大提高系统集... 针对数据管控和综合智能运维的需要,对中心、车站、车辆段/停车场系统设备从架构上进行整合设计,对各子系统进行集成或接口互联,在统一的平台上对各专业系统设备进行监视和控制。通过分析,采用综合运营调度的单轨系统可大大提高系统集成化程度,精简作业岗位,有效降低建设和运维成本。综合运营调度系统可实现各专业资源互通共享,在发生突发事件或设备故障时,能在统一的综合平台内为用户提供完整丰富的信息支持,通过智能联动等自动控制技术手段,可显著提高运营效率。综合运营调度系统方案符合单轨交通系统一体化、集成化、简约化的发展方向,将是未来我国单轨交通运营控制系统的发展趋势。 展开更多
关键词 单轨交通 综合运营调度系统 深度集成 建设方案
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洪奇沥公铁两用大桥主桥边跨组合梁设计及施工方案研究
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作者 刘振标 夏正春 +3 位作者 印涛 胡方杰 徐伟伟 姜洪劲 《铁道标准设计》 北大核心 2025年第5期95-102,共8页
洪奇沥公铁两用大桥是新建深圳至江门铁路的关键性控制工程,公铁分层布置,上层为8车道城市快速路,下层为4线铁路。主桥采用(3×100+808+3×100) m超短边跨钢混箱-桁组合梁斜拉桥,一跨跨越洪奇沥水道,无工程先例可借鉴。结合建... 洪奇沥公铁两用大桥是新建深圳至江门铁路的关键性控制工程,公铁分层布置,上层为8车道城市快速路,下层为4线铁路。主桥采用(3×100+808+3×100) m超短边跨钢混箱-桁组合梁斜拉桥,一跨跨越洪奇沥水道,无工程先例可借鉴。结合建设条件、结构特点以及技术经济性,对边跨主梁结构设计及施工方案展开研究。结果表明,主梁采用矩形钢管混凝土叠合板-桁组合梁,将结构受力和对拉索的锚固压重融于一体,并在边跨施工阶段充分发挥连续钢桁梁自身高承载力特性和叠合板现浇层以预制板为底模的优势,节省模板和临时工程,具有显著的经济效益;钢桁梁采用“纵向分段横向分块安装+多点步履式顶推”的施工方案,有效解决超宽、超高钢桁梁水运运输受通航条件限制的难题,并适应边跨位于岸上的大吨位钢梁架设;边跨施工采用部分支撑临时墩方案,临时墩反力较完全支撑临时墩方案减小46.2%,临时工程量少,并且避免了不设临时墩方案中主跨架设对边跨混凝土浇筑的扰动影响,叠合板-桁组合梁施工质量高;现浇混凝土采用“先受压区后受拉区、先管内后管外”的分段浇筑方案,较一次浇筑方案,上、下层桥面板最大名义拉应力分别减小81.8%、76.0%,有效改善混凝土结构受力。 展开更多
关键词 公铁合建桥 斜拉桥 叠合板-桁组合梁 结构设计 施工方案
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争创一流学科:中国大学的行动框架及其调试逻辑
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作者 凌健 许怀安 《黑龙江高教研究》 北大核心 2025年第3期105-111,共7页
在建设教育强国的政策牵引下,我国高校创建世界一流学科的行动逐渐替代入选身份受到更多关注,如何建成世界一流以及选择何种路径必须被理性审视。借助于政策注意力视角,分析并讨论了75份“双一流”建设大学方案蕴含的行动框架及其特征,... 在建设教育强国的政策牵引下,我国高校创建世界一流学科的行动逐渐替代入选身份受到更多关注,如何建成世界一流以及选择何种路径必须被理性审视。借助于政策注意力视角,分析并讨论了75份“双一流”建设大学方案蕴含的行动框架及其特征,从管理、服务和价值等三重逻辑提出高校创建行动应调试的方向。 展开更多
关键词 一流学科 行动框架 建设方案 政策牵引
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锦屏中微子探测器及其结构选型要求
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作者 王元清 陈少敏 +4 位作者 王综轶 王喆 李贝贝 叶全喜 林子倩 《工业建筑》 2025年第3期34-41,共8页
锦屏中微子实验(JNE)的探测器位于中国锦屏地下实验室,是新一代混合型中微子探测器。由于实验室的空间约束、中微子物理研究的要求、实验运行的管理规定等因素,使探测器及其结构选型在工程设计上面临一系列挑战性的课题。探测器包含不... 锦屏中微子实验(JNE)的探测器位于中国锦屏地下实验室,是新一代混合型中微子探测器。由于实验室的空间约束、中微子物理研究的要求、实验运行的管理规定等因素,使探测器及其结构选型在工程设计上面临一系列挑战性的课题。探测器包含不锈钢结构、有机玻璃球结构,合成纤维绳索支撑结构等。不锈钢结构包括储存屏蔽缓冲液的箱体以及安装光电倍增管的网壳;有机玻璃球是探测器的核心容器,采用合成纤维绳索作为支撑。讨论在上述约束条件下对探测器各部分的选型要求,为探测器的设计与安装提供策略性的方案。 展开更多
关键词 锦屏中微子探测器 不锈钢结构 有机玻璃球 高性能纤维绳索 施工方案
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乐业县岜木水库工程主要设计方案研究
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作者 刘惠娟 《云南水力发电》 2025年第7期80-82,共3页
以岜木水库工程为依托,对工程的主要设计方案和施工现场处理技术开展了探讨与研究。由于工程地理环境特殊,存在场地受制约、地质条件差和施工技术要求高等困难,对此,从坝址位置、坝型选择、石料场选址和供水管道布设等4个方面对工程的... 以岜木水库工程为依托,对工程的主要设计方案和施工现场处理技术开展了探讨与研究。由于工程地理环境特殊,存在场地受制约、地质条件差和施工技术要求高等困难,对此,从坝址位置、坝型选择、石料场选址和供水管道布设等4个方面对工程的主要设计方案进行了研究和分析,并以现场实际问题为导向,有针对性提出了施工现场处理关键技术。 展开更多
关键词 岜木水库 设计方案 施工现场 处理技术 关键技术
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Test Study on Navigation in the First Construction Period of Lize Navigation-Power Junction
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作者 Kai Chen 《Engineering(科研)》 2016年第6期332-338,共7页
Based on the test results of Lize navigation-power junction construction diversion through the normal fix-bed model with the scale of 1:100, the navigation flow condition in each construction diversion period is studi... Based on the test results of Lize navigation-power junction construction diversion through the normal fix-bed model with the scale of 1:100, the navigation flow condition in each construction diversion period is studied. There are a lot of problems in the first construction diversion period, such as excessive flow velocity, poor flow pattern, low navigation discharge and so on. To solve these problems, the comprehensive engineering measures for improving the navigation flow condition during construction are put forward. Among them, the structure forms of construction diversion cofferdam are optimized. Finally, the highest safe navigation discharge and reasonable navigation route are proposed. The experimental results obtained from the optimization scheme of the first construction diversion period are better than these from the original scheme in terms of flow velocity, flow pattern and so on. The research results may serve as reference for similar engineering. 展开更多
关键词 Navigation-Power Junction construction Diversion Navigation Condition Experimental Research Optimization schemes
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高强韧抗滑磨耗层在高速公路沥青路面养护中的应用 被引量:1
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作者 蒋建飞 赵跃 +4 位作者 郭阳阳 王伟伟 武昊 李明亮 李俊 《交通节能与环保》 2025年第1期180-184,共5页
为了恢复高速公路沥青路面的抗滑性能,使用高强韧超薄磨耗层(Strength and Toughness Course,STC)置换路表以下1.5 cm的旧混合料。首先,提出STC-8(公称最大粒径7.5 mm)磨耗层的具体技术方案;其次,对STC-8磨耗层混合料进行配合比设计,检... 为了恢复高速公路沥青路面的抗滑性能,使用高强韧超薄磨耗层(Strength and Toughness Course,STC)置换路表以下1.5 cm的旧混合料。首先,提出STC-8(公称最大粒径7.5 mm)磨耗层的具体技术方案;其次,对STC-8磨耗层混合料进行配合比设计,检验并分析其路用性能;最后,通过工程实践验证STC-8磨耗层的应用效果。检验结果显示,STC-8磨耗层混合料在60℃高温下的动稳定度超过8000次/mm,在-10℃低温下的弯曲破坏应变超过2800με,表明STC-8磨耗层混合料具有优良的强度和韧性。铺筑STC-8磨耗层后,路面构造深度大于0.6 mm,摆值大于80,横向力系数大于60。工程验证表明STC磨耗层可作为恢复路面抗滑性的一种潜在技术措施。 展开更多
关键词 道路工程 高强韧磨耗层 抗滑处治 配合比设计 施工方案 应用效果
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工程掘进机成套化施工工艺研究
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作者 王秀梅 祝溪明 《内燃机与配件》 2025年第13期111-113,共3页
工程掘进机作为新型隧道施工装备,在隧道机械化施工中得到越来越广泛地应用。论文在分析工程掘进机与传统TBM及钻爆法施工工艺特点的基础上,研究了工程掘进机全断面施工及台阶法施工工法,探讨了工程掘进机后配出渣工艺、隧道配套除尘技... 工程掘进机作为新型隧道施工装备,在隧道机械化施工中得到越来越广泛地应用。论文在分析工程掘进机与传统TBM及钻爆法施工工艺特点的基础上,研究了工程掘进机全断面施工及台阶法施工工法,探讨了工程掘进机后配出渣工艺、隧道配套除尘技术、掘进机配电方案以及机械化初支台架技术。通过百合隧道的工程掘进机施工工艺验证,论证了掘进机施工效率与施工成本,对提高隧道施工机械化程度,推进工程掘进机施工标准化,完善我国暗挖隧道施工工法具有重要意义。 展开更多
关键词 工程掘进机 施工工法 隧道除尘 配电方案 支护台架
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成渝中线简阳沱江特大桥主桥上部结构施工技术 被引量:1
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作者 李传富 李永乐 +1 位作者 马天亮 张大兵 《桥梁建设》 北大核心 2025年第2期146-152,共7页
新建成渝中线简阳沱江特大桥主桥为(72+320+72)m中承式无推力组合拱桥,主拱为钢管混凝土拱,边拱为钢-混组合箱拱,边拱端部拱梁一体,主梁作为系杆,成都侧拱座设纵向活动支座。根据该桥结构特点、水文和地质条件、无砟轨道线形精度要求,... 新建成渝中线简阳沱江特大桥主桥为(72+320+72)m中承式无推力组合拱桥,主拱为钢管混凝土拱,边拱为钢-混组合箱拱,边拱端部拱梁一体,主梁作为系杆,成都侧拱座设纵向活动支座。根据该桥结构特点、水文和地质条件、无砟轨道线形精度要求,边拱采用支架法施工,在主拱合龙前和二期恒载施工前分2次浇筑边拱压重混凝土,以平衡拱脚混凝土应力和边支座的反力;主拱分为三大段,两端73 m拱段采用原位支架拼装方案施工,跨中174 m拱段采用“低位拼装、整体垂直提升”方案施工;主梁采用支架法施工,在主梁跨中合龙段设置临时拉索,主动张拉合龙,同时可通过临时拉索的多次主动张拉将成都侧拱座滑移量控制在20 mm内;在成都侧拱座往中跨侧滑移的方向上设置临时约束,利用支座垫石作为限位挡块,限制主拱合龙前拱座往中跨侧的滑移。 展开更多
关键词 高速铁路桥 无推力组合拱桥 钢管混凝土拱 钢-混组合箱拱 边拱压重 整体提升 临时约束 施工方案
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Construction of <i>k</i>-Variate Survival Functions with Emphasis on the Case <i>k</i>= 3
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作者 Jerzy K. Filus Lidia Z. Filus 《Applied Mathematics》 2020年第7期678-697,共20页
The purpose of this paper is to present a general universal formula for <span style="font-family:Verdana;"><span style="font-family:Verdana;">k<span style="font-family:Verdana;&... The purpose of this paper is to present a general universal formula for <span style="font-family:Verdana;"><span style="font-family:Verdana;">k<span style="font-family:Verdana;"><span style="font-family:Verdana;">-variate survival functions for arbitrary <span style="font-family:Verdana;"><span style="font-family:Verdana;">k<span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> = 2, 3, <span style="font-family:;" "=""><span style="font-family:Verdana;">...<span style="font-family:Verdana;">, given all the univariate marginal survival functions. This universal form of <span style="font-family:Verdana;"><span style="font-family:Verdana;">k<span style="font-family:Verdana;"><span style="font-family:Verdana;">-variate probability distributions was obtained by means of “dependence functions” named “joiners” in the text. These joiners determine all the involved stochastic dependencies between the underlying random variables. However, in order that the presented formula (the form) represents a legitimate survival function, some necessary and sufficient conditions for the joiners had to be found. Basically, finding those conditions is the main task of this paper. This task was successfully performed for the case <span style="font-family:Verdana;"><span style="font-family:Verdana;">k<span style="font-family:Verdana;"><span style="font-family:Verdana;"> = 2 and the main results for the case <span style="font-family:Verdana;"><span style="font-family:Verdana;">k<span style="font-family:Verdana;"><span style="font-family:Verdana;"> = 3 were formulated as Theorem 1 and Theorem 2 in Section 4. Nevertheless, the hypothetical conditions valid for the general <span style="font-family:Verdana;"><span style="font-family:Verdana;">k<span style="font-family:Verdana;"><span style="font-family:Verdana;"> ≥ 4 case were also formulated in Section 3 as the (very convincing) Hypothesis. As for the sufficient conditions for both the <span style="font-family:Verdana;"><span style="font-family:Verdana;">k<span style="font-family:Verdana;"><span style="font-family:;" "=""><span style="font-family:Verdana;"> = 3 and <span style="font-family:Verdana;"><span style="font-family:Verdana;">k<span style="font-family:Verdana;"><span style="font-family:Verdana;"> ≥ 4 cases, the full generality was not achieved since two restrictions were imposed. Firstly, we limited ourselves to the, defined in the text, “continuous cases” (when the corresponding joint density exists and is continuous), and secondly we consider positive stochastic dependencies only. Nevertheless, the class of the <span style="font-family:Verdana;"><span style="font-family:Verdana;">k<span style="font-family:Verdana;"><span style="font-family:Verdana;">-variate distributions which can be constructed is very wide. The presented method of construction by means of joiners can be considered competitive to the <span style="font-family:Verdana;"><span style="font-family:Verdana;">copula<span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> methodology. As it is suggested in the paper the possibility of building a common theory of both copulae and joiners is quite possible, and the joiners may play the role of tools within the theory of copulae, and vice versa copulae may, for example, be used for finding proper joiners. Another independent feature of the joiners methodology is the possibility of constructing many new stochastic processes including stationary and Markovian. 展开更多
关键词 construction of Multivariate Probability Distributions via Joiners Joiner versus Copula Methodology A Possible Fusion of the Two construction Methods k -Variate Survival Function scheme k = 3 Case
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特殊地质地区桥梁工程施工方案虚拟模糊决策技术研究
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作者 杨静 段鹏鑫 +2 位作者 何于秋 汪辉 段晓晨 《科学技术与工程》 北大核心 2025年第10期4292-4299,共8页
特殊地质地区的施工决策极为重要且复杂多变,地质条件的不确定性会直接影响施工方案的选择和实施。为解决西南复杂特殊地质地区桥梁工程施工方案“五控”目标(工期、成本、质量、安全、环保)之间非均衡性难题,将网络计划技术与建筑信息... 特殊地质地区的施工决策极为重要且复杂多变,地质条件的不确定性会直接影响施工方案的选择和实施。为解决西南复杂特殊地质地区桥梁工程施工方案“五控”目标(工期、成本、质量、安全、环保)之间非均衡性难题,将网络计划技术与建筑信息模型(building information modeling,BIM)可视化技术、模糊集理论和灰色关联分析(grey relational analysis,GRA)集成应用到复杂特殊地质地区桥梁工程施工方案优选中,建立基于工期-成本-质量-安全-环保的混合模糊多属性决策模型(hybrid fuzzy multi-attribute decision-making model,HFMD),并运用Python与BIM技术构建施工过程可视化系统,辅助管理人员进行决策,结果满足“五控”指标综合优化方案,并且工期提前10 d,成本降低3.1%,证明了此模A型和方法的实用性和有效性。为复杂特殊地质地区桥梁工程施工方案决策提供了参考。 展开更多
关键词 模糊集 施工方案优选 灰色关联分析 混合模糊多属性决策 施工过程可视化
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西堠门公铁两用大桥主桥5号桥塔墩深水基础钻孔平台方案比选研究
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作者 吕磊 梁玉坤 +1 位作者 王东辉 涂满明 《世界桥梁》 北大核心 2025年第5期18-23,共6页
甬舟铁路西堠门公铁两用大桥主桥为主跨1488 m的斜拉-悬索协作体系桥,5号桥塔墩基础采用18根∅6.3 m超大直径空心钻孔灌注桩基础,桩基嵌入岩层40 m左右,墩位处最大水深57.4 m、无覆盖层且海床面高差达8 m左右,水文环境及波浪条件恶劣。... 甬舟铁路西堠门公铁两用大桥主桥为主跨1488 m的斜拉-悬索协作体系桥,5号桥塔墩基础采用18根∅6.3 m超大直径空心钻孔灌注桩基础,桩基嵌入岩层40 m左右,墩位处最大水深57.4 m、无覆盖层且海床面高差达8 m左右,水文环境及波浪条件恶劣。为保证5号桥塔墩基础钻孔灌注桩顺利施工,提出导管架平台方案和钢桁架平台方案,并从施工工期、用钢量、大型设备、施工难度及风险方面进行比选,确定采用钢桁架平台方案。钢桁架为整体全焊式,高10.9 m,采用8根∅4.8 m钢锚桩+4根∅6.8 m钢护筒支撑桩作为平台支撑体系,桁架与钢锚桩之间固结形成“板凳式”结构,同时在桁架底部设置内嵌式浮箱结构,使钻孔平台结构具备整体自浮功能及便于∅4.8 m钢锚桩插打施工。 展开更多
关键词 公路铁路两用桥 斜拉-悬索协作体系桥 钻孔灌注桩 钻孔平台 整体全焊式钢桁架结构 内嵌式浮箱结构 整体自浮功能 施工方案
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