预应力混凝土梁受硫酸盐腐蚀后的力学性能研究

对经受硫酸盐溶液浸泡腐蚀后的预应力混凝土梁进行了全面的试验研究,分析了试验梁在经受不同浓度硫酸盐溶液短期和长期浸泡腐蚀后力学性能的变化规律,为在硫酸盐环境下工作的混凝土结构耐久性研究提供了参考依据.     

Distortional buckling tests of cold-formed steel compression members at elevated temperatures

In recent times, light gauge cold-formed steel sections have been used extensively since they have a very high strength to weight ratio compared with thicker hot-rolled steel sections. However, they are susceptible to various buckling modes including a distortional mode and hence show complex behaviour under fire conditions. Therefore, a research project based on detailed experimental studies was undertaken to investigate the distortional buckling behaviour of light gauge cold-formed steel compression members under simulated fire conditions. More than 150 axial compression tests were undertaken at uniform ambient and elevated temperatures. Two types of cross sections were selected with nominal thicknesses of 0.60, 0.80, and 0.95 mm. Both low (G250) and high (G550) strength steels were used. Distortional buckling tests were conducted at six different temperatures in the range of 20-800 ^°C. The ultimate loads of compression members subject to distortional buckling were then used to review the adequacy of the current design rules at ambient and elevated temperatures. This paper presents the details of this experimental study and the results.     

桥梁常备式结构在盖梁悬空支架中的应用

以忠县长江大桥忠县岸引桥盖梁悬空支架施工为例,阐述了采用常备式结构贝雷梁、万能杆件作为悬空支架来浇筑盖梁的技术,列举支架设计计算实例以及施工要点,指出该方法结构简洁,受力明确,安全可靠且具有较好的经济性。     

All Night Long: The Architectural Jazz of the Texas Rangers

In the mid-1950s, a group of young faculty at the University of Texas School of Architecture in Austin - aka the Texas Rangers - entertained themselves with weekly sessions of a sophisticated, collective drawing game, ‘Dot-the-Dot’, in which there was an emphasis on inventive fluency in hand drawing as well as an innate knowledge of historic European city plans. What happened when Mark Morris , Visiting Associate Professor at Cornell University, decided in a design studio to ask present-day students to revive the game?     

双层球面网壳的序列地震效应敏感性研究

为了研究双层球面网壳结构响应对于序列地震是否敏感、避免结构在主震后的余震作用下发生倒塌,首先建立了基于通用有限元软件ABAQUS的结构有限元模型,并对太平洋地震工程研究中心(PEER)数据库中的主余震序列地震动数据进行了筛选,共收集到342对主余震序列地震动时程数据;利用全荷载域动力时程分析方法,获得了各序列地震作用下结构的特征响应随加速度幅值的变化规律,归类并定义了网壳结构多重地震效应的四种影响程度;然后,对大量算例的结果进行统计,得到了在主震结束时的网壳特征响应(最大节点位移、屈服杆件比例和结构损伤因子)与结构抵抗余震能力的关系;最终将屈服杆件比例作为衡量双层球面网壳抵抗余震能力的指标,并给出了各跨度双层球面网壳屈服杆件比例的敏感界限值。研究成果可为网壳结构的抗震设计及抗震性能评估提供参考。     

冷弯薄壁钢类椭圆截面轴压构件设计方法

为研究冷弯薄壁钢空心类椭圆截面轴心受压构件的有限元数值模拟及设计方法,考察了现行冷弯薄壁钢结构设计规范中的有效宽度法对该类型截面构件的适用性．采用Abaqus建立冷弯薄壁钢空心类椭圆该模型可以准确地模拟此类构件的力学性能截面轴心受压构件的非线性有限元数值模型．有限元模型计算结果与试验结果的比较表明,该模型可以准确地模拟...     

现阶段企业离退休职工思想政治工作的重要性及对策

做好离退休职工的思想政治工作是坚决贯彻党的思想政治工作路线、方针的具体表现,也是构建社会主义和谐家庭的基本要求。现阶段我们的离退休职工思想政治工作既面临着难得的机遇也可能会遇到一些不可避免的困难。我们可以主要从加强支部建设、落实生活待遇、开展多种多样的活动、教育和自我学习相结合几个方面去做好离退休职工思想政治工作。     

试论高校党员主体地位的确立

维护高校党员的主体地位,对实现和谐发展、提高党委执政能力、培养可靠接班人具有重要意义。但高校存在着党员主体作用发挥不够、主体保障机制缺失等问题,究其原因,在于传统观念、社会心理、主体素质等方面的影响,所以,高校应坚持权利本位、民主集中制、制度与机制保障等基本原则,通过环境营造、党性锤炼、学习教育、主体机制、加强研究等现实路径来确立党员的主体地位。     

水工混凝土结构设计规范基本构件的相当安全系数的计算分析

以我国现行DL/T 5057-1996"水工混凝土结构设计规范"中的轴心受拉、受弯、受剪、受扭、轴心受压、大偏心受压、小偏心受压、板受冲切等8种典型的基本构件为例,从相当安全系数的角度,对DL/T 5057-1996规范承载能力极限状态的安全度设置水平进行了计算分析,结果表明,当作用效应比值较小时,采用分项系数设计表达式进行设计时较为经济;当作用效应比值较大时,采用系数设计表达式进行设计时更为合理,使得所设计的结构构件在安全可靠与经济合理之间,在不同设计条件下都能达到一种较佳的平衡.