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多桥驱动车辆越障时轴荷动态分配研究  [PDF]
魏道高,区颖刚,杨丹彤,刘庆庭
农业机械学报 , 2011,
Abstract: 轴荷动态分配规律是影响多桥驱动非路面车辆可靠性的主要因素,为了获得越障时的轴荷,建立了四桥驱动越障时轴荷动态分配动力学模型。对某型四桥驱动山地车辆进行了计算与分析,获得附着系数φ为0.1~1.0越障时各桥轴荷分配量,结果表明,该车辆越障时轴荷动态分配值差异较大,第4桥轴荷总是呈现较大值,导致各桥的疲劳寿命不一致。
闽江南港洪塘大桥桥位河段特性分析  [PDF]
朱颖元,郑振
福州大学学报(自然科学版) , 2005,
Abstract: 从水力、水文和泥沙条件、河道和断面形态、深泓线变化、河底高程变动、河道冲淤情况、上游水口水库蓄水和桥位河段内采砂等方面分析了洪塘大桥桥位河段的特性.结果显示,洪塘大桥桥位河段属于宽浅型不稳定变迁性河段
少筋混凝土肋腋板组合梁桥的试建  [PDF]
娄有原
公路交通科技 , 1990,
Abstract: 本文简述少筋混凝土肋腋板组合梁桥的设计与试验概况.通过静载试验得到的横向分布系数、主梁挠度和钢筋应力,均与计算值基本符合,表明所采用的翼缘分布宽度及横向分布系数是合理的,也表明主梁和肋腋板组合的整体性能良好.由于肋腋板跨径较大,这种桥型因可减少主梁片数而对宽桥更为适用.
从微域地貌和岩石组成探讨广西驾桥岭东北部六塘河谷的冰川地貌  [PDF]
地质论评 , 1965,
Abstract: 孙殿卿对广西东北部驾桥岭-六塘的冰川地貌曾进行过研究。驾桥岭为一穹窿山,中部
弯梁桥中V-T联合受荷桩承载力分析  [PDF]
邹新军, 王亚雄, 徐洞斌
中国公路学报 , 2015,
Abstract: ?为探讨弯梁桥中基桩在竖向力V和扭矩T共同作用下的受力特性,考虑土体剪切模量和桩侧极限摩阻力沿深度线性增加(Gibson地基),并计入加载路径和桩-土接触面位移非协调性的影响,基于桩身荷载传递函数和剪切位移法建立桩身位移控制方程,引入相应的力和位移边界条件后,导出桩周土处于不同受力状态时的桩身内力位移解析解,由此求得不同加载路径下V-T联合受荷桩的承载力,进而获得桩身承载力包络图。研究结果表明:对于V-T联合受荷桩,桩身承载力随长径比增加而增加,但随桩侧土体剪切模量与极限摩阻力分布常数之比和桩土刚度比的增大而逐渐减小;桩顶可承受的竖向力随扭矩增加不断减小而趋于0,且V→T承载力包络线始终处于T→V承载力包络线外侧。
小塘子特宽桥荷载试验与分析方法研究  [PDF]
徐显芬,林胜,王成
重庆交通大学学报(自然科学版) , 2012, DOI: 10.3969/j.issn.1674-0696.2012.01.07
Abstract: :?随着城市交通建设的发展,我国出现了宽跨比较大的城市桥梁。此类桥横向分布效应较常规桥梁明显,以传统的桥梁平面计算程序计算活载作用效应会带来误差。针对一座宽跨比约2.3的简支空心板桥梁进行结构平面和空间加载分析,分别计算加载后桥梁的变形和应力,并与实际加载测量的变形和应力结果进行比较,分析两者的差别,为实际工程提供参考。
贵州岑巩羊桥罗家塘杷榔动物群的发现及其后生动物早期演化的意义  [PDF]
马海涛,彭进,赵元龙,达扬,孙海静
地质论评 , 2011,
Abstract: 岑巩县羊桥乡罗家塘杷榔组仅出露中―上部地层,岩性单一,均为青灰、灰绿色粉砂质泥、页岩。在其上部层位发现了俞氏贵州始海百合(GuizhoueocrinusyuiZhao,ParsleyetPeng,2007),计有棘皮动物始海百合、腕足动物、软体动物――软舌螺、节肢动物――三叶虫等8属9种,包括了2个未定名的新种和1未定种,与凯里市杷榔组的杷榔动物群相似。新的发现扩展了杷榔动物群的地理分布,提供了群落生态及埋藏学研究的新材料,具有重要的科学和实践意义。
微型桩支撑引板的无缝桥试设计研究
Trial-design Study on Jointless Bridge with Approach Slab Supported by Micro-piles
 [PDF]

,,庄一舟,陈宝春
- , 2017,
Abstract: 为研究微型桩支撑引板的无缝桥受力性能,进行了这种新型无缝桥的试设计,采用MIDAS/Civil建立了考虑微型桩?餐料嗷プ饔玫娜?桥空间有限元模型,对比分析了试设计桥与原桥在恒载作用、汽车荷载作用、引板沉降下的受力行为,以及温度作用、收缩徐变效应、引板与接线路面间伸缩量下的受力行为;采用模态分析和地震时程分析方法研究了桥梁自振特性和地震响应。结果表明:竖向荷载作用下试设计桥的主梁边跨正弯矩减少,同时引板沉降减少;微型桩的约束作用会使主梁在升温、降温、收缩徐变作用下的轴力增大;试设计桥在地震荷载作用下位移反应减少,提高了桥梁的抗震性能;该研究成果可为微型桩支撑引板的无缝桥设计提供借鉴,对该新型无缝桥在实际工程中的应用和发展起到推动作用。
In order to study the mechanical behavior of jointless bridge with approach slab supported by micro-piles, trial-design of the new type structure was carried out, and the full bridge spatial finite element model considering micro-pile-soil interaction was built by MIDAS/Civil. The mechanical behaviors of the trial-design bridge and the original bridge under constant load, automobile load and approach slab settlement were compared and analyzed. The mechanical behaviors of the bridges under temperature, shrinkage and creep, and the expansion between approach slab and approach pavement were also analyzed. The natural vibration characteristics and seismic response of the bridge were studied by modal analysis and seismic time history analysis. The results show that the positive bending moment of the side span of the trial-design bridge main beam under vertical load decreases, while the settlement of approach slab decreases. The restraint effect of the micro-pile will increase the axial force of the main beam under the influence of temperature rise, temperature drop, and shrinkage and creep. The displacement response of the trial-design bridge under seismic loading is reduced, and the seismic performance of the bridge is improved. The study can provides references for the design of jointless bridge with approach slab supported by micro-piles, and can promote the development and application of this new kind of jointless bridge in the actual engineering
采用UHPC-RC阶梯桩的整体桥试设计
Trial-design Study on Integral Abutment Bridge by Using UHPC-RC Stagewise Piles
 [PDF]

陈宝春,陈国栋,苏家战,林上顺,薛俊青,TABATABAI Habib
- , 2018,
Abstract: 为了增大桥台基础柔度,适应整体桥纵桥向变形需要,提出了上部采用超高性能混凝土(UHPC)材料、下部采用普通混凝土(RC)材料的UHPC-RC阶梯桩,进行了这种新型桩基整体桥的试设计,在桩顶3 m范围内用截面尺寸为30 cm×30 cm的UHPC代替原来的70 cm×50(70) cm普通混凝土,并采用MIDAS软件建立了全桥空间有限元模型。研究结果表明:恒载作用下,试设计桥梁端负弯矩相比于原桥明显减小;在偏载和中载作用下,试设计桥主梁在桥台处的负弯矩分别减小14.2%和22.8%;整体降温作用下,主梁的轴力和弯矩均都有显著减小,桩身的最大剪力和最大弯矩出现在桩顶位置,分别减小52.2%,59.8%;在整体升温作用下,桥台的最大剪力和最大弯矩出现在桥台顶部位置,分别减小32.6%,45.8%;UHPC-RC阶梯桩是一种适合中国国情、有发展前景的无缝桥桩基新结构。
A UHPC-RC stagewise pile with ultra high performance concrete (UHPC) was proposed to increase the flexibility of the foundation and adapt to the longitudinal deformation of the integral bridge. The trial-design of integral abutment bridge employing such a new kind pile was performed. In the top 3 m of the pile, UHPC with 30 cm×30 cm section was used to instead of the original 70 cm×50(70) cm RC. The finite element model of the whole bridge was established by using MIDAS software. The study results show that negative bending moment at the end of the beam in the trial-design bridge is obviously reduced compared to the original bridge under dead load. The negative bending moments decrease about 14.2% and 22.8% respectively under offset load and central load. When the temperature drops, the axial force and bending moment of beam are significantly reduced. The maximum shear force and bending moment of the pile occur at the top of the pile, and they decrease about 52.2%, 59.8%, respectively. When the temperature rises up, the maximum shear force and bending moment of the abutment appear at the top of the abutment, and decrease by 32.6% and 45.8%, respectively.Trial-design study indicates that UHPC-RC stagewise pile is a new type pile which is suitable to be used in integral bridge in China
模糊预后验决策  [PDF]
系统工程理论与实践 , 1994,
Abstract: ?本文旨在把模糊数学方法同贝叶斯决策中的预后验决策方法相结合,提供了一个处理这类决策中出现的一些模糊性的方法。这种方法适用范围更广,更接近日常生活中遇到的决策问题。
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