Design of steel box girder for Taizhou Yangtze River Highway Bridge

Taizhou Yangtze River Highway Bridge is the first three-pylon two-span suspension bridge in China. The main girder adopts flat steamline steel closed box girder which has well wind-resistant capability and is technically mature besides beautiful appearance. Straight web plates of the steel box girder in longitudinal direction are proposed in order to ensure the integrity of the steel box girder, and to keep the stress of the steel box girder continuous in the middle pylon, as well as to reduce the gradient of the middle pylon columns. The cross section of the box girder has one box with three cells. Solid-web diaphragm plate with good integrity and high torsional stiffness is adopted. The lifting lugs are utilized in the anchors of suspender cable. In this paper, selection of the cross section of the steel box girder, the general structure design, local structure design and main structure calculation results of Taizhou Yangtze River Bridge are introduced emphatically.     

Study on effects of environmental temperature on dynamic characteristics of Taizhou Yangtze River Bridge

The dynamic characteristics of three-tower and two-span suspension bridge are analyzed at different global temperatures. An equivalent cable inner force method is proposed to consider temperature effects and to study the effects of environmental temperature on dynamic characteristics of Taizhou Yangtze River Bridge. The result demonstrates that the effects of temperature can not be neglected in static or dynamic analysis of Taizhou Yangtze River Bridge. The relationship between temperature and frequency is negative. The effects of temperature should be taken into account in experimental modal analysis of long-span bridges and damage identification.     

The mechanical response of multi tower continuous span suspension bridge deck pavement based on whole bridge analysis

The effect of multiple span suspension structure on the mechanical response of bridge deck pavement was studied, and finite element analysis (FEM) of stress and strain of pavement according to the bridge floor system features of super-long and high flexibility was made. Meanwhile, the FEM results were compared with those of the single span suspension structure. Three-stage analytic hierarchy process (AHP) is developed to analyze the mechanical response including whole bridge analysis, partial beams section analysis and orthotropic plate analysis. The most unfavorable load position was determined by the numerical solutions acquired from each stage to study the main mechanical index of multiple span suspension structure. The FEM results showed that the mechanical response numerical solutions by using the three-stage AHP are greater than those by simplified boundary condition, and the force condition of multiple span suspension structure is worse than that of the single span suspension structure.     

油气耦连悬架系统的建模与仿真研究

针对车辆轮荷的显著差异会降低车辆的平顺性和驱动能力这一问题,提出了一种油气耦连悬架系统.首先介绍了该系统的结构和原理,并在Matlab/Simulink下搭建了其动力学模型,最后将该模型与车辆动力学仿真软件Carsim进行联合仿真,在不平路面下对是否装有该耦连悬架系统车辆的侧倾角、不足转向度、发动机输出功率等指标进行仿...     

高固含固液搅拌槽内颗粒悬浮与混合特性

对高固含体系下Intermig桨搅拌槽内的桨叶搅拌性能以及颗粒的混合与悬浮特性进行实验研究.采用光导纤维技术对不同桨径、搅拌转速和桨叶离底距离下搅拌槽内底部以及轴向颗粒密度进行测量,同时对临界悬浮转速和搅拌功率进行测定.实验结果表明:对高固含液-固搅拌体系,所采用的Intermig搅拌桨具有很好的轴向混合特性,该桨适合在较大的桨径和较低的桨叶离底距离下应用,可在促进颗粒悬浮与均匀分布的同时,大大降低功率消耗.通过对实验结果的分析和拟合得出底部均匀度与搅拌槽内弗劳德数有关,Q=0.58Fr-0.35,Intermig搅拌桨功率准数在0.2 ～0.3之间,且与雷诺数关系为NP=2.1Re-0.2.     

组合悬移支架炮采放顶煤工艺在古书院矿的应用

介绍了ZHZ1600/16/24型组合悬移支架炮采放顶煤工艺在13310煤柱工作面的应用,指出了该工艺存在的问题及应采取的措施,说明了采用新工艺后的煤回收率及经济效益。     

Distal流的有关性质

研究了紧度量空间上distal流的有关性质，得出以下结论：1）紧度量空间上的同胚是distal同胚当且仅当它的扭扩流是distal流；2）Distal流经提升或提射后仍是distal流。     

Aerostatic Stability of Long-Span Cable-Stayed Bridges: Parametric Study

The increasing span of cable-stayed bridges has focused more attention on the aerostatic stability of the design and construction of such bridges. This paper presents a new method to analyze the nonlinear aerostatic stability of cable-stayed bridges including all three components of the wind load and the geometric nonlinearity. The analysis was used to investigate the effects of the wind angle of incidence, the wind load of individual bridge elements, the sagging of cable elements, the changes of tower height and the changes of side span length on the aerostatic stability of cable-stayed bridges. The results show that the wind angle of incidence and the wind loads on the cables have an important effect on the aerostatic stability of cable-stayed bridges.     

高分散高稳定BaTiO3水基悬浮液制备的研究

采用胶体电空间稳定机制改善陶瓷粉体的分散性,以聚合物电解质PMAA—NH_4为分散剂,利用Zeta电位、沉降实验、粘度测定和粒度分析等手段,研究了分散剂的用量和pH值对BaTiO_3水基悬浮液流变性的影响,并在最佳分散剂用量和pH值条件下,制备出了高分散高稳定的BaTiO_3水基悬浮液。图4,参11。     

失落的男性--解读阎连科90年代的小说

寻找女人是阎连科小说中男性的一种存在目的.农民和士兵的双重身份使这些男人处在一种悬浮而异化的生存状态,承受着面对女人和面对自身的双重价值失落.在这样的一种价值消解的外衣下,作家对男性价值作了重新的追寻和定位.