高速公路破损现浇箱梁拆除及重建

京石高速公路K175＋132白陀北沟桥是我省正在运营的高速公路中首次进行破损现浇连续箱梁拆除施工的工程。随着我国国民经济的发展,高速公路的通车里程越来越多,相应地许多突发事故对桥梁的损害也将增多,如何尽快地修复受损的桥梁,保障高速公路的畅通,是未来公路工程养护及施工中必须解决的一个问题。本文通过该工程的施工,介绍怎样合理选用现阶段比较成熟的技术,对受损的桥梁现浇连续箱梁上部结构进行快速拆除及重建的经验。     

Later life learning experiences: listening to the voices of Chinese elders in Hong Kong

Abstract

Governments’ anxieties about ageing populations are mostly concerned with the costs of welfare, care and health provision which all have to be paid for by an ever dwindling working population. However, research in later life learning indicates the significant role that lifelong learning can play in promoting mental well-being and resilience, and in assisting with maintaining personal self-confidence and self-coping strategies that prevent cognitive decline in an ageing population. This paper draws on the research with a group of Chinese elders in Hong Kong, who provide information about their experiences and views on learning in later life, including the meaning of learning, barriers to participation, learning interests, needs, motivations, and instructional preferences. Both quantitative and qualitative findings are reported to shed light on later life learning experiences, which contribute to the global understanding of later life learning and serve to inform the development of policy and practice geared to the planning and provision of opportunities to keep learning at the later stages of life.     

Flexural Behaviour of High－Strength Steel Fiber－Reinforced Concrete Beams

ＦｌｅｘｕｒａｌＢｅｈａｖｉｏｕｒｏｆＨｉｇｈ－ＳｔｒｅｎｇｔｈＳｔｅｅｌＦｉｂｅｒ－ＲｅｉｎｆｏｒｃｅｄＣｏｎｃｒｅｔｅＢｅａｍｓＱｉａｎＣｈｕｎｘｉａｎｇ（钱春香）（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅｅｒｉ...     

锚杆框架梁支护在雪道边坡防护中的应用

随着我国经济的快速发展,基础设施发展迅速,建设过程中新的施工技术层出不穷,其中对于工程岩体分化严重、结构面较发育的高挖方边坡,通常采用锚杆框架梁结构支护。然而,对于高山滑雪中心滑雪赛道两侧高陡边坡,除了要实现边坡稳定的同时还需考虑如何防止雪道污染的问题。本文结合北京2022年冬奥会高山滑雪中心第二标段的工程实践,详细阐述了兼具边坡支护和防止雪道污染的锚杆框架梁支护体系的设计原则、设计内容、施工工艺,并说明了施工中的一些细节或要点。实践证明该支护体系合理,不仅确保了边坡的安全稳定和防止了雪道污染,同时具有造价低、施工机动性强的特点,可以在类似的雪道施工中推广。     

用高斯光束单丝衍射来监测拉丝工艺中的细丝直径

提出一种用动态法测细丝直径的方法。用微机配合可以监测拉丝工艺中的细丝直径,精度在5％以内。     

三门海特大桥高桩承台钢吊箱设计与施工

阐述三门海大桥用有底钢吊箱修建深水高桩承台的设计与施工要点,总结出深水高桩承台的干作业施工技术及注意事项,既可保证工程质量,又节省时间和费用,有一定的经济、社会效益。     

微型同位素辐射能收集器二维悬臂梁机电建模

基于欧拉-伯努利梁理论,设计了一种新型的微型同位素辐射能收集器二维机电模型。该模型解决了一维机电模型无法涵盖的诸多问题。算例分析表明:本模型能较准确地描述实验过程和预测实验结果。通过对结果进行分析,得出了影响微悬臂梁的位移、梁的往返周期和梁中存储能量的一系列因素。     

On group and phase velocities manifested through exact solutions to the equations of some propagation phenomena

A system of non-Hermite, non-orthogonal functions that are new for concrete applications is introduced to generate explicit and previously unknown, physically meaningful solutions for bar and plate equations. The approach allows in some cases to establish completeness of these sets of solutions. Various other separate results technically related to these basic development are presented. In the available literature there are no registered efforts to extract the two velocities from exact solutions of the equations of the processes in which the two parameters are explicitly present.     

环状光束辐照下光学薄膜基底温度场有限元分析

基于热传导方程,利用有限元分析方法,利用MSC.Marc有限元软件建立了激光辐照下光学薄膜基底温度场的三维模型,研究了光学薄膜基底在环状光束辐照下的温度场分布,并进行了分析.     

北京奥运会女子平衡木决赛动作分析与研究

第29届奥运会已经在北京顺利圆满的结束,中国以51金的历史最好成绩位列金牌榜首位。中国体操军团也以9金的成绩取得历史新的突破。但在平衡木项目上中国两名实力选手皆因出现失误而无缘金牌。通过录像统计和资料研究,对平衡木决赛运动员的成套技术动作难度及连接加分还有出现的失误进行分析和研究,为该项目的发展提供参考。