南疆复线公路桥主桥箱梁悬浇设计与施工

天津港南疆复线公路桥是南疆港区的一座新建跨海大桥,大桥为港区特载标准,主桥为5跨悬浇变截面连续梁,分幅建设后,横向合拢形成一幅桥。该文介绍了南疆复线公路桥主桥的悬浇设计、施工及控制,为日后此类桥梁设计及施工借鉴学习。     

金融危机下基于CCFI指数的中美航线集装箱班轮运价研究

运用CCFI指数,通过对美国经贸形势和中美航线运量运力的调查分析,解析金融危机下2008—2009年中美航线集装箱班轮运价的波动过程,并简要地对2010年的中美航运市场进行展望。     

长玻纤增强型材料在汽车前端模块中的应用

介绍长玻纤增强型材料的定义、种类,从力学角度研究玻纤长度对材料机械性能的影响。最后阐述长玻纤增强型材料完全可以取代钣金用在汽车前端模块上,实现轻量化。     

Prediction of tire natural frequency with consideration of the enveloping property

A lumped tire model was developed with consideration of the enveloping property in order to predict the natural tire frequency. Tire stiffness was classified into vertical, sidewall, and enveloping stiffnesses, and the tire characteristics were analyzed in detail experimentally and via finite element analysis. In addition, the effective masses of the tire tread and belt were extracted directly from design specifications taking into account the sizes and material properties of different rubber blocks. Using the design parameters of the tires, natural frequencies were calculated from the derived model and were compared with experimental results. Finally, based on good agreement with experimental results, sensitivity analysis was performed to verify the effect of tire stiffnesses on the natural frequencies.     

Numerical Simulation and Optimization Design of Electromagnetic Fields in the Electromagnetic Casting of Copper Round Billet

IntroductionInrecentyOars,e1eCtrOmngneticcontinuouscashngtechnologyhasbeenexPerimentngandusinginmostcoUntris,WhichgainedwideaPPicathasinnon-ferrOUsmetalichstry.Atthesamehme,anUmerofsCholarshavecalculatedandmeasuredelectromagneticfields.MapnehqfieldmodelsofmpOREandMSlllhasgainedwideaPPlicationsinthesemodels.Someolsemodels,suchasH-offormula,alsohaVdescribeddistributingofelectromapneticfieldinelectromngneticcontinuouscashngwellandttuly.Electromapneticcontinuouscashngwithsofucontactmoldha…     

胎儿内耳外淋巴锌、铜、钙定量分析

采用阳极溶出法和化学发光法分别对胎儿内耳外淋巴锌、铜、钙含量及铜／锌比值进行定量分析，初步提出人体内耳外淋巴锌、铜、钙含量及比值的正常参考值，并建立了一种测定外淋巴的微量分析方法，此法用量少、灵敏度高、结果可靠，为耳聋的诊治提供参考依据。     

Comprehensive Evaluation of the Intelligent Degree of the Mining Face Based on Grey Relational Analysis北大核心CSCD

In order to further evaluate the intelligent degree of the coal mining face scientifically and reasonably, this paper constructs a gray relational analysis based comprehensive evaluation model for the intelligent degree of mining face by deeply analyzing the influencing factors on the intelligent degree of mining face, such as surrounding rock detection, mining equipment, production system, supporting production system, organization and management, etc. By quantifying and scoring factors affecting the intelligence degree of mining face, using the hierarchical analysis method to obtain the weights and determine the correlations, the intelligence degrees of mining face are classified into four levels: excellent, good, medium and poor. Using the comprehensive evaluation model to empirically verify the 802 working face of Shaanxi Huangling Mining Co., Ltd., the calculated correlation is 0.765 8, which indicates that the intelligent degree of 802 working face is excellent according to the rating criteria, and it is consistent with the actual situation. Therefore, the comprehensive evaluation model based on gray relational analysis can accurately and objectively evaluate the intelligent degree of the mining face. © 2022, Editorial Office of "Modern Tunnelling Technology". All right reserved.     

西安北客站至机场城际轨道交通项目投融资及运营补亏方案分析

参考国内相关项目投融资模式,分析了西安北客站至机场城际轨道交通项目的投融资及运营补亏方案。采取政府主导、多元化投资方式,对于解决资金难题、促进项目实施起到了有效作用。通过项目财务状况分析,提出了土地经营、物业开发、争取低息贷款、采用单一电价等运营补亏的建议。     

安全风险评估在煤系易滑地层边坡综合整治后的应用

结合地质调绘、边坡病害调查和监测成果,对综合整治后的煤系易滑地层边坡-以清云高速公路地豆服务区AK0+353~AK0+513右侧路堑边坡为例,进行安全风险评估(包括适宜性评价、稳定性评价和安全风险评价),划分安全风险等级并提出适宜的应对措施,为高速公路的安全运营管理提供基础依据。     

BIM技术在重庆曾家岩嘉陵江大桥设计中的应用

重庆曾家岩嘉陵江大桥为(135+270+135)m刚性加劲悬索连续钢桁架公轨双用桥,上层为城市主干道路,下层为城市交通轨道,大桥路线走廊狭窄,桥址古今建筑密集、地下管网轨道交错繁杂、地形起伏显著。该桥设计中应用Bentley和Autodesk平台软件进行BIM技术协同设计,基于BIM平台软件,创建了三维地形模型和工程周边实景模型,在此基础上确定了最佳路线,通过桥型方案比选确定了连续钢桁架桥方案;建立钢桁架、桥墩等主要结构参数化模型,进行结构参数化设计;通过构件碰撞检测校核、桥墩防撞模拟、交通流模拟和工程量校核等,实现大桥优化设计。与传统二维设计相比,基于BIM技术优化该桥设计方案,大量节省了设计成本,有效地提高了桥梁设计质量,提升了整个工程管理水平。