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| 1 | Characterization of horseshoe vortex in a developing scour hole at a cylindrical bridge pier显示文摘Since local scour at bridge piers in rivers and estuaries is a major cause of bridge failure, estimation of the maximum local scour depth is of great importance to hydraulic and coastal engineers. Although numerous studies that focus on scour-depth prediction have been done and published, understanding of the flow and turbulence characteristics of the horseshoe vortex that drives the scour mechanism in a developing scour hole still is immature. This study aims to quantify the detailed turbulent flow field in a developing clear-water scour hole at a circular pier using Particle Image Velocimetry (PIV). The distributions of velocity fields, turbulence intensities, and Reynolds shear stresses of the horseshoe vortex that form in front of the pier at different scour stages (t=0, 0.5, 1, 12, 24, and 48 h) are presented in this paper. During scour development, the horseshoe vortex system was found to evolve from one initially small vortex to three vortices. The strength and size of the main vortex are found to increase with increasing scour depth. The regions of both the maximum turbulence intensity and Reynolds shear stress are found to form at a location upstream of the main vortex, where the large turbulent eddies have the highest possibility of occurrence. Results from this study not only provide new insight into the complex flow-sediment interaction at bridge piers, but also provide valuable experimental databases for advanced numerical simulations. | Dawei Guan Yee-Meng Chiew Maoxing Wei Shih-Chun Hsieh | 2019 | International Journal of Sediment Research2019，34，2： | 8 |
| 2 | Local scour around two side-by-side cylindrical bridge piers under ice-covered conditions显示文摘In the current study, 108 flume experiments with non-uniform, cohesionless sediments have been done to investigate the local scour process around four pairs of side-by-side bridge piers under both open channel and ice-covered flow conditions. Similar to local scour around bridge piers under open channel conditions and a single bridge pier, it was observed in the experiments that the maximum scour depth always occurred at the upstream face of the pier under ice-covered conditions. Further, the smaller the pier size and the greater the spacing distance between the bridge piers, the weaker the horseshoe vortices around the bridge piers, and, thus, the shallower the scour holes around them. Finally, empirical equations were developed to estimate the maximum scour depth around two side-by-side bridge piers under both open channel and ice-covered flow conditions. | Mohammad reza Namaee Jueyi Sui | 2019 | International Journal of Sediment Research2019，34，4： | 7 |
| 3 | Shake table study on precast segmental concrete double-column piers显示文摘Seismic capacity,including the ultimate load-carrying capacity and ultimate deformation capacity of precast segmental concrete double-column(PSCDC)piers with steel sleeve(SS)connection or grouted corrugated-metal duct(GCMD)connection,has been verified to be similar to those of cast-in-place(CIP)piers by quasi-static tests.However,the lack of knowledge of seismic response characteristics and damage process of PSCDC piers has limited their application in high-intensity seismic areas.Therefore,shake table tests,using variable types and intensities of seismic ground motions,were performed to investigate the seismic behavior of connection joints and to evaluate the seismic performance of PSCDC piers with SS and GCMD connections.Also,a finite element analysis(FEA)model was developed to study the influence of design parameters on the seismic behavior of the piers.The results showed that the main damage in PSCDC piers was caused by the cyclic opening and closing of connection joints.Under high-intensity ground motions,the PSCDC piers had a lower seismic performance than the CIP piers due to a significant decrease of their integrity and stiffness.The seismic performance of PSCDC piers is comparable to CIP piers when using an appropriate initial stress of the prestressing tendons. | Xia Zhanghua Ge Jiping Lin Youqin Qiu Faqiang | 2020 | Earthquake Engineering and Engineering Vibration2020，19，3： | 5 |
| 4 | Numerical Analysis of Interaction Between Pile-Supported Pier and Bank Slope显示文摘Two- and three-dimensional finite element analysis programs for pile-soil interaction are compiled. Duncan-Chang's Model is used. The construction sequence of the pier is modeled. The pile-soil interface element is used. The influence of the combination type of piles on the deformation of bank slope and pile behaviour is analyzed. Different designs of a pile-supported pier are compared thoroughly. Calculation results show that the stresses and displacements of the pile are directly related to the distance from the bank slope and the direction of inclination. An inclined prop pile set in the rear platform would remarkably reduce the stresses of piles and the displacement of the pier. | WANG Nianxiang(王年香) | 2001 | China Ocean Engineering2001，16，1： | 5 |
| 5 | The design philosophy and bridge's technical innovation of Hong Kong- Zhuhai-Macao Bridge显示文摘This article introduces the project overview, construction goal and design philosophy of Hong Kong- Zhuhai-Macao Bridge. Based on large scale, factory production, standardization and assemble line, the innova- tive concept is taken as the general principle for design with the emphasis on description of the new material, new technology, new construction method and new equipment used in the design. The application of innovative technology has provided a solid foundation and favorable guarantee for project quality and design service | Meng Fanchao Liu Minghu Wu Weisheng Zhang Gejun Zhang Liang | 2014 | Engineering Sciences2014，12，3： | 3 |
| 6 | Simulation of two-phase debris flow scouring bridge pier显示文摘Debris flows are typical two-phase flows, which commonly accompany erosion in mountainous areas, and may destroy bridge engineering by scouring. In this study, a physically-based two-phase model is applied for the simulation of debris flow scouring of bridge pier. In this model, the shear stress of debris flow on an erodible bed is considered to be a function of the solid shear stress, fluid shear stress, and volume fraction; accordingly, the erosion is incorporated into the two-phase model. Using a highaccuracy computational scheme based on the finite volume method, the model is employed for simulating a dynamic debris flow over an erodible bed. The numerical results are consistent with the experimental data, and verify the feasibility of the two-phase model. Moreover, a simple numerical test is performed to exhibit the fundamental behaviour of debris flow scouring of bridge pier, which shows that the degree of erosion on each side of the pier is higher compared to other areas. The scouring depth is influenced by the variations of solid volume fraction and velocity of debris flow and pier width. | LIU Wei HE Si-ming | 2017 | Journal of Mountain Science2017，14，11： | 2 |
| 7 | X-Gal培养基+PCR法快速鉴定酸奶中双歧杆菌显示文摘目的:探讨一种简易快速酸奶中双歧杆菌的鉴别方法。方法:在MRS培养基中添加一定量X-Gal(5-溴-4-氯-3-吲哚-α-D-半乳糖苷),通过对标准双歧杆菌和乳酸菌混合菌及双歧杆菌和乳酸菌发酵的酸奶进行检测,对该培养基上不同颜色的菌落提取DNA作PCR鉴定。结果:在X-Gal培养基上呈白色或浅兰色菌落经PCR鉴定为双歧杆菌,而呈深兰色菌落经PCR鉴定未出现双歧杆菌特征性条带。结论:在X-Gal培养基上双歧杆菌和乳酸菌有明显鉴别性,可用于双歧杆菌和乳酸菌混合发酵的酸乳制品菌落鉴别计数。 | 江晓 陈晓蔚 曾理 贾力敏 丁洁 | 2005 | 现代预防医学2005，32，12： | 2 |
| 8 | Wave Forces and Moments on a Gravity Pier Foundation显示文摘In order to understand the wave forces and moments on a gravity pier foundation which consists of an upper column and a bottom gravity base,a model experiment with a scale of 1:60 has been conducted in a laboratory flume.A corresponding numerical calculation by using the boundary element method has been carried out to provide a comparative analysis.It is shown by the comparisons that the numerical wave forces and moments agree well with the experimentai results.It is proved that the wave forces and moments acting on the foundation are completely in their inertia dominative areas for wave loads.With the diffraction effects considered into the inertia item,appropriate inertia coefficients are assessed by the experimentai results for the inertia item of the Morison equation.The formula of the inertia item can be used to estimate wave forces and moments on such gravity foundations. | 韦承勋 周道成 欧进萍 | 2019 | Journal of Shanghai Jiaotong university(Science)2019，24，3： | 1 |
| 9 | 熊去氧胆酸可改善胆固醇性胆石症患者的胆囊收缩功能显示文摘意大利的Michele Pier Luca Guarino在6月的Gut上报道,通过各种机制,熊去氧胆酸(UDCA)治疗可缓解胆固醇性胆石症患者的症状。 | | 2007 | 中华医学信息导报2007，22，13： | 1 |
| 10 | Interaction Between Pile-Supported Pier and Bank Slope显示文摘- Generally the toe of the bank slope in front of the pile- supported pier has to be dredged to meet the requirements of water depth for the berth of ships, while the top of the slope in rear of the pier must be backfilled and elevated to make connections with land transportation. Then the natural state of equilibrium of the slope is destroyed, and some deformation and displacement are unavoidably induced in the soil mass which will exert an undesirable influence on the pile foundation of the pier. This is a typical problem of the interaction between the so-called 'passive pile' and surrounding soil, and has been scarcely studied in the literature of geotechnical engineering. In this paper, field observation, model tests and numerical analysis conducted by the authors to study the interaction between pile-supported pier and bank slope are briefly described and some preliminary results are presented. | Wei Rulong , Wang Nianxiang Yang Shouhua Prof., Senior Engineer, Nanjing Hydraulic Research Institute, 210029 Nanjing Engineer, Nanjing Hydraulic Research Institute, 210029 Nanjing | 1992 | China Ocean Engineering1992，7，2： | 1 |
| 11 | Influence of Long-term Climate on Fatigue Life of Bridge Pier Concrete and a Reinforcement Method显示文摘This paper quantitatively evaluated the fatigue life of concrete around the air-water boundary layer of bridge piers located in inland rivers,considering the long-term climate.The paper suggests a method to predict the low-cycle fatigue life by demonstrating a thermal-fluid-structural analysis of bridge pier concrete according to long-term climate such as temperature,velocity and pressure of air and water in the process of freezing and thawing in winter.In addition,it proposes a reinforcing method to increase the life of damaged piers and proves the feasibility of the proposed method with numerical comparison experiment. | Nam-Hyok Ri Kum-Hyok So Yong-Sop Ri Zhiyao Ma Yong-Ae Kim Hui-Gwang Yun | 2019 | Hydro Science & Marine Engineering2019，1，1： | 0 |
| 12 | Nonlinear Wave Force on Pier Group in Shallow Water显示文摘Based on the 1st order cnoidal wave theory, the wave diffraction around the pier group inshallow water is studied in this paper. The formulas for calculating the nonlinear wave forces are also presented here. In order to verify the theoretical results, model tests are conducted in the wave flume in The State Key Laboratory of Coastal and Offshore Engineering located in Dalian University of Technology. The range of the wave parameters in the experiments is characteristic wave period T g/d1/2 = 8.08- 22.86, characteristic wave height H/ d= 0.1 0.45. The results obtained from the experiments agree with the theoretical results quite well. It is shown that, in shallow water the nonlinear wave forces acting on a pier group are greater than those calculated by linear wave theory, the value of increment in wave force increases with the increases of the nonlinearity of the wave. In the wave range studied in this paper, the nonlinear wave force can reach over 4 times the force calculatecd by linear wave theory. Thus, it is suggested that, when Tg / d1/2> 8, the wave force on the piers in the pier group in shallow water should be calculated by using the cnoidal wave theory. | Qiu Dahong , Zhou Yuanheng and Jia Ying Professor, Dept. of Civil Engineering, Dalian University of Technology, Dalian Lecturer, Dept. of Civil Engineering, Dalian University of Technology, Dalian | 1992 | China Ocean Engineering1992，7，1： | 0 |
| 13 | Brief Account of Breakwater Construction in China显示文摘-The construction of breakwaters in China in more than 40 years since the founding of the People’s Republic of China is reviewed. The construction of two main types of breakwater, upright breakwaters and rubble mound breakwaters, and the way in which they are built are expounded. Recommendations to improve the technology for future breakwater construction are presented. | Chai Changqing Chief Engineer, First Navigational Engineering Bureau, Ministry of Communications of China, Jianjin | 1994 | China Ocean Engineering1994，9，1： | 0 |
| 14 | Comparison of Scour and Flow Characteristics Around Circular and Oblong Bridge Piers in Seepage Affected Alluvial Channels显示文摘The present study examines scour geometry and turbulent flow characteristics around circular and oblong piers in alluvial channel with downward seepage.Experiments were conducted in plane sand bed of non-uniform sand under no seepage,10%seepage and 15%seepage conditions.Scour depth at oblong pier is significantly lesser than the scour depth at circular one.However,the scour depth at both piers reduces with downward seepage.The measurements show that the velocity and Reynolds stresses are negative near the bed at upstream of piers where the strong reversal occurs.At downstream of oblong pier near the free surface,velocity and Reynolds stresses are less positive;whereas,they are negative at downstream of circular pier.The streamline shape of oblong pier leads to reduce the strength of wake vortices and consequently reversal flow at downstream of pier.With application of downward seepage turbulent kinetic energy is decreasing.The results show that the wake vortices at oblong pier are weaker than the wake vortices at circular pier.The strength of wake vortices diminishes with downward seepage.The Strouhal number is lesser for oblong pier and decreases with downward seepage for both oblong and circular piers. | Rutuja Chavan B.Venkataramana Pratik Acharya Bimlesh Kumar | 2018 | Journal of Marine Science and Application2018，17，2： | 0 |
| 15 | RANDOM ANALYSIS OF HYDRODYNAMIC CHARACTERIS-TICS OF TRAJECTORY JET CAUSED BY DIFFERENT TYPES OF PIERS显示文摘This paper presents s ome results on different tail patterns of piers with an overflow dam, and di scusses in particular the hydrodynamic characteristics, the distance of water je t scour and the range of erosion area fluctuating for different parameters of av erage flow field when river beds are under the pressure of water jet scour cause d by some special broad-tail piers. The present paper also covers some prelimin ary research on the relationship of movable bed tests, and introduces the method of calculating the erosion depth and area, therefore provides the best pier pat tern in the construction of river beds against erosion. | Cui, Li Wang, Qingguo Wang, Yongtao | 2000 | Journal of Hydrodynamics2000，12，3： | 0 |
| 16 | Probability-based practice-oriented seismic behaviour assessment of simply supported RC bridges considering the variation and correlation in pier performance显示文摘Probability-based seismic performance assessment of in-service bridges has gained much attention in the scientific community during the past decades. The nonlinear static pushover analysis is critical for describing the seismic behaviour of bridges subjected to moderate to high seismicity due to its simplicity. However, in existing analysis methods,the generation of pushover curve needs tremendous amount of computational costs and requires skills, which may halter its application in practice, implying the importance of developing practice-oriented analysis method with improved efficiency. Moreover, the bridge pier performance has been modelled as deterministic, indicating that the variation associated with the pier material and mechanical properties remains unaddressed. The correlation in the performance of different piers also exists due to the common design provisions and construction conditions but has neither been taken into account. This paper develops a simplified pushover analysis procedure for the seismic assessment of simply supported RC bridges. With the proposed method, the pushover curve of the bridge can be obtained explicitly without complex finite element modelling. A random factor is introduced to reflect the uncertainty in relation to the pushover curve. The correlation in the pier performance is considered by employing the Gaussian copula function to construct the joint probability distribution. Illustrative examples are presented to demonstrate theapplicability of the method and to investigate the impact of variation and correlation in bridge pier behaviour on the seismic performance assessment. | Long Zhang Cao Wang | 2018 | Journal of Traffic and Transportation Engineering(English Edition)2018，5，6： | 0 |
| 17 | “NAVY PIER”赢利有道显示文摘 | 李春晖 | 2000 | 北京商业2000，，3： | 0 |
| 18 | Experimental Study of Wave Pressure on a Breakwater Pier显示文摘Test studies on the wave pressure on a breakwater pier show that the influence of transmissivewave pressure on the outside wall of the breakwater pier is considerable,when the width of the pier is notvery large.The variations of transmissive wave pressure on the breakwater pier with different widths arecompared and the relationship is obtained between relative transmitting distance b/L and wave pressurereduction factor K,which may be used in the design of similar breakwater piers. | Pan, SH Xia, QY Lin, SQ Xu, LH | 1999 | China Ocean Engineering1999，14，2： | 0 |
| 19 | AN APPROACH TO ANALYSIS OF SINGLE PIER BASED ON THE VARIATIONAL PRINCIPLE IN MULTI-LAYERED SOIL显示文摘In this study,a variational approach to the settlement analysis of an axially loaded pier em-bedded in a multi-layered soil profile is presented.In this method,the soil profile and the embedded pier aredivided into a number of sub-layers according to the actual number of soil layers observed in the field.Thedisplacement shape function of each soil layer is given as a product of an exponential equation along the pierdepth and the Bessel’s solution in the radial direction.The displacement relationship among the layers can bederived through the transformation matrices.One of the major features of this method is that the total numberof pier elements is the same as that of soil sub-layers.All the field compontents,such as the displacement,stress,and strain in the soil,can be calculated by closed-form solutions except that the only unknown vari-able is the value β which can be determined by iteration techniques.Comparisons were made with the resultsof finite element analysis and the field observation in pile-loaded tests. | NG Shiu Cho | 2001 | Acta Mechanica Solida Sinica2001，14，3： | 0 |
| 20 | 高墩连续刚构桥抗震分析与设计显示文摘本文运用有限元软件Midas/Civil建立有限元模型,对石马河大桥进行了模态分析;分别用反应谱法和时程响应分析法计算了该桥的地震响应,并对两种方法的计算结果进行比较分析。 | 徐宏广 | 2007 | 湖北水利水电职业技术学院学报2007，0，1： | 0 |
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