scholarly journals Analysis of Water Flow Pressure on Bridge Piers considering the Impact Effect

2015 ◽  
Vol 2015 ◽  
pp. 1-8
Author(s):  
Yin-hui Wang ◽  
Yi-song Zou ◽  
Lue-qin Xu ◽  
Zheng Luo
Keyword(s):  
Water Flow ◽  
Coupling Effect ◽  
Highway Bridges ◽  
Element Model ◽  
Bridge Pier ◽  
Bridge Piers ◽  
Water Current ◽  
Fluid Structure ◽  
Impact Effect ◽  
The Impact

In order to investigate the effects of water current impact and fluid-structure interaction on the bridge piers, the mechanism of water flow impact on the bridge pier is firstly studied. Then a finite element model of a bridge pier is established including the effects of water flow impact as well as the water circumferential motion around the pier. Comparative study is conducted between the results of water impact effect, fluid-structure coupling effect, theoretical analysis, and also the results derived using the formulas specified in the design codes home and abroad. The results show that the water flow force calculated using the formulas provided by the codes should be multiplied by an impact amplifier to account for the effect of flood impact on the bridge pier. When the flood flows around the pier, the fluid-structure coupling effect on the bridge pier can be neglected. The method specified in the China guidelines ofGeneral Code for Design of Highway Bridges and Culvertstends to provide a larger result of the water flow force.

Numerical analysis of collision between a tractor-trailer and bridge pier

2018 ◽  
Vol 9 (4) ◽  
pp. 484-503 ◽  
Author(s):  
Luwei Chen ◽  
Hao Wu ◽  
Qin Fang ◽  
Tao Zhang
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Impact Force ◽  
Element Model ◽  
Bridge Pier ◽  
Bridge Piers ◽  
Highway Bridge ◽  
Heavy Duty ◽  
The Impact ◽  
The Finite Element Model

Accidents involving collisions of heavy-duty trucks with highway bridge piers occurred occasionally, in which the bridge piers might be subjected to severe damage, and cause the collapse of the superstructure due to the loss of axial loading capacity. The existing researches are mostly concentrated on the light- or medium-duty trucks. This article mainly concerns about the collisions between the heavy-duty trucks (e.g. tractor-trailer) and bridge piers as well as the evaluation of the impact force. First, by modifying the finite element model of Ford F800 single-unit truck, which was developed by National Crash Analysis Center, the finite element model of a tractor-trailer is established. Then, the full-scale tractor-trailer crash test on concrete-filled steel pier jointly conducted by Texas Transportation Institute, Federal Highway Administration, and Texas Department of Transportation is numerically simulated. The impact process is well reproduced and the established model is validated by comparison of the impact force. It indicates that the tractor-trailer impact force time history consists of two or three peaks and the corresponding causes are revealed. Furthermore, the parametric influences on the impact force are discussed, including the diameter and cross section shape of the pier, cargo weight, impact velocity, relative impact position, and vehicle type. Finally, the finite element model of an actual reinforced concrete highway bridge pier is established, and the impact force and lateral displacement of the pier subjected to the impact of the tractor-trailer are numerically derived and discussed.

scholarly journals Effect of Angle between Pier and Center of River Flow on Local Scouring around the Bridge Pier

Water ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 3192
Author(s):  
Takuma Kadono ◽  
Shinichiro Okazaki ◽  
Yoshihiro Kabeyama ◽  
Toshinori Matsui
Keyword(s):  
Water Flow ◽  
Heavy Rainfall ◽  
River Flow ◽  
Bridge Pier ◽  
Bridge Piers ◽  
Flowing Water ◽  
River Flows ◽  
Scouring Depth

In recent years, heavy rainfall disasters have caused frequent damage to bridge piers due to scouring and have resulted in the fall of bridges in many areas in Japan. The objective of this study was to investigate the effect of local scouring around the downstream of the piers on the local scouring around the center of the river flowing at an angle to the piers. It was found that when the center of the river flows at an angle to the piers, the scouring area becomes wider from the upstream to the downstream of the piers because of the longer inhibition width of the piers positioned perpendicular to the water flow. The downstream scouring depth tends to be smaller than the upstream scouring depth. In addition, the time to the onset of tilting deformation of the piers increases with the inhibition width of the piers positioned perpendicular to the flowing water.

Dynamic Modeling and Fluid-Structure Interactive Analysis of an Innovative Self-Tuning Shock Absorber for the Prosthesis Knee Joint

2010 ◽  
Author(s):  
Yen-Chieh Mao ◽  
Wei-Chih Chang
Keyword(s):  
Knee Joint ◽  
Shock Absorber ◽  
Knee Prosthesis ◽  
Element Model ◽  
Heel Strike ◽  
Design Parameters ◽  
Fluid Structure ◽  
Shock Absorbers ◽  
Damper Design ◽  
The Impact

The above-knee prosthesis, as a supplement of the lost biological leg, is supposed to provide equivalent or enhanced shock absorption capability and reduce the shock waves on the amputee body when walking and running. Prosthesis knee joint with a shock absorber is a feasible solution that efficiently absorbs the impact loads during each heel-strike. Conventional shock absorbers consist of springs and dampers with constant coefficients produce excessive rigid reactions when encountering impact forces, while unreasonable weak responses for gentle loads. This study proposes an innovative viscous damper design for the prosthesis knee joint which automatically and smoothly tunes the damping coefficient without any electronic components according to the input force velocities. High order differential system of the shock absorber is constructed and simulates the system dynamics during cyclic loads. The fluid-structure interactive finite element model for key components in the absorber is established in this study. Design parameters of the damper system under certain absorbing performance requirements are determined in this paper.

On the problem of using the bridge span as a tuned mass damper of bridge pier oscillation

2019 ◽  
pp. 24-30
Author(s):  
Olga Nesterova
Keyword(s):  
Critical Mass ◽  
Practical Importance ◽  
Tuned Mass Damper ◽  
Bridge Pier ◽  
Bridge Piers ◽  
Optimal Parameters ◽  
Bridge Span ◽  
Mass Damper ◽  
Effective Use ◽  
The Impact

Objective: To identify the area of effective use of bridge span as a tuned mass damper of bridge pier oscillation during earthquake in seismic areas. Methods: Numerical simulation of oscillations of the “bridge pier with span” system under both the impact set by the harmonic rule and the records of past earthquake accelerograms. Results: The area of effective use of bridge span structures as a tuned mass damper of bridge piers’ oscillation during earthquake in seismic areas has been defined. The concept of the relative critical mass of the span used as a tuned mass damper of bridge piers’ oscillation during earthquake has been introduced. When the spun structure mass reaches the critical value, the effect of the tuned mass damper disappears. The dependences of the optimal parameters of the connection between the span and pier on the relative span mass used as a tuned mass damper have been obtained. It has been found that the span critical mass used as a tuned mass damper decreases when the pier damping increases, and the dependences of the optimal parameters of the connection between the span structure and the pier on the damping in the pier body have been obtained. Practical importance: The possibility of using span as a tuned mass damper of piers is shown. The optimum characteristics of the span and its connection with the pier body have been obtained to be used in designing. The use of span as a tuned mass damper in piers can significantly reduce labor input and the cost of bridge building in seismic areas. It also facilitates the elimination of consequences of devastating earthquakes.

Numerical Analysis of Bridge Caisson Foundation due to Riverbed Erosion

2013 ◽  
Vol 405-408 ◽  
pp. 342-348
Author(s):  
Wen Tsung Liu ◽  
Chia Chyi Chang ◽  
Kuei Hsiang Cheng ◽  
Chen Wei Chi
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Water Flow ◽  
Warning System ◽  
Bridge Pier ◽  
Scour Depth ◽  
Flood Level ◽  
Simulating Analysis ◽  
The Impact ◽  
Element Method

Keywords： Scour Depth, Water flow Force, Finite Element Method ABSTRACT. In recent years, the researches on the impact stability of piers based on river erosion are concerned in Taiwan. Therefore, it is an important issue to estimate accurately the scour depth, to calculate the water flow force on bridge pier, and to establish the close mechanism of bridge for saving lives. This research is a case study on Paulon Bridge by finite element method (FEM) Plaxis 3D Foundation for simulating analysis the caisson foundation in bridge pier scour. Firstly, we infer the flood level, the speed of flow in the different frequency year, the whole bridge safety coefficient, and the inclination angle of pile based on the simulating analysis to build the warning system. We compare the data by FEM and observing data in order to confirm the validity of FEM.

scholarly journals The impact of bridge pier on ice jam evolution – an experimental study

2016 ◽  
Vol 64 (1) ◽  
pp. 75-82 ◽  
Author(s):  
Jun Wang ◽  
Jian Hua ◽  
Jueyi Sui ◽  
Peng Wu ◽  
Tao Liu ◽  
...  
Keyword(s):  
Thickness Distribution ◽  
Early Spring ◽  
Bridge Pier ◽  
Bridge Piers ◽  
Ice Jam ◽  
Laboratory Flume ◽  
Different Diameters ◽  
Hydraulic Process ◽  
Different Characteristics ◽  
The Impact

AbstractThe ice jam in a river can significantly change the flow field in winter and early spring. The presence of bridge piers further complicates the hydraulic process by interacting between the ice jam and bridge piers. Using the data collected from experiments in a laboratory flume, the evolution of an ice jam around bridge piers having three different diameters has been investigated in this study. Compared to results without-pier, it was found that the formation of an ice jam in the downstream of bridge pier is faster than that in the upstream. The thickness distribution of the ice jam shows clearly different characteristics in front and behind of bridge piers at different stages of the ice jam.

scholarly journals Seismic Design Method of Self-Centring-Segment Bridge Piers with Tensile-Type Viscoelastic Dampers

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Huixing Gao ◽  
Yang Song ◽  
Wenting Yuan ◽  
Hongxu Lu ◽  
Shuo Cao
Keyword(s):  
Seismic Design ◽  
Design Method ◽  
Element Model ◽  
Bridge Pier ◽  
Bridge Piers ◽  
Earthquake Excitation ◽  
Viscoelastic Dampers ◽  
Displacement Based ◽  
Seismic Design Method ◽  
Stiffness And Damping

This paper aims to study the deformational behaviour of tensile-type viscoelastic dampers under different earthquake excitation directions. A method for calculating the corresponding equivalent additional stiffness and damping of a self-centring-segment bridge pier is derived. Using the displacement-based seismic design method, a design method for self-centring-segment bridge piers with tensile-type viscoelastic dampers is proposed. Using the proposed method, a self-centring-segment bridge pier is designed. Based on dynamic analysis of the finite element model by OpenSees, the effectiveness of the proposed seismic design method is validated.

scholarly journals Mechanical Stability of Hybrid Corrugated Sandwich Plates under Fluid-Structure-Thermal Coupling for Novel Thermal Protection Systems

2020 ◽  
Vol 10 (8) ◽  
pp. 2790
Author(s):  
Wenzheng Zhuang ◽  
Chao Yang ◽  
Zhigang Wu
Keyword(s):  
Mechanical Stability ◽  
Thermal Protection ◽  
Element Model ◽  
Parameter Study ◽  
The Novel ◽  
Thermal Coupling ◽  
Mechanical Instability ◽  
Fluid Structure ◽  
Thermal Protection Systems ◽  
Protection Systems

Hybrid corrugated sandwich (HCS) plates have become a promising candidate for novel thermal protection systems (TPS) due to their multi-functionality of load bearing and thermal protection. For hypersonic vehicles, the novel TPS that performs some structural functions is a potential method of saving weight, which is significant in reducing expensive design/manufacture cost. Considering the novel TPS exposed to severe thermal and aerodynamic environments, the mechanical stability of the HCS plates under fluid-structure-thermal coupling is crucial for preliminary design of the TPS. In this paper, an innovative layerwise finite element model of the HCS plates is presented, and coupled fluid-structure-thermal analysis is performed with a parameter study. The proposed method is validated to be accurate and efficient against commercial software simulation. Results have shown that the mechanical instability of the HCS plates can be induced by fluid-structure coupling and further accelerated by thermal effect. The influences of geometric parameters on thermal buckling and dynamic stability present opposite tendencies, indicating a tradeoff is required for the TPS design. The present analytical model and numerical results provide design guidance in the practical application of the novel TPS.

scholarly journals Probabilistic seismic response analysis of coastal highway bridges under scour and liquefaction conditions: does the hydrodynamic effect matter?

2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Xiaowei Wang ◽  
Yutao Pang ◽  
Aijun Ye
Keyword(s):  
Seismic Response ◽  
Seismic Design ◽  
Highway Bridges ◽  
Element Model ◽  
Response Analysis ◽  
Hydrodynamic Effect ◽  
Strong Earthquakes ◽  
Influence Of Water ◽  
Scour Hazard ◽  
Ground Motion Records

AbstractCoastal highway bridges are usually supported by pile foundations that are submerged in water and embedded into saturated soils. Such sites have been reported susceptible to scour hazard and probably liquefied under strong earthquakes. Existing studies on seismic response analyses of such bridges often ignore the influence of water-induced hydrodynamic effect. This study assesses quantitative impacts of the hydrodynamic effect on seismic responses of coastal highway bridges under scour and liquefaction potential in a probabilistic manner. A coupled soil-bridge finite element model that represents typical coastal highway bridges is excited by two sets of ground motion records that represent two seismic design levels (i.e., low versus high in terms of 10%-50 years versus 2%-50 years). Modeled by the added mass method, the hydrodynamic effect on responses of bridge key components including the bearing deformation, column curvature, and pile curvature is systematically quantified for scenarios with and without liquefaction across different scour depths. It is found that the influence of hydrodynamic effect becomes more noticeable with the increase of scour depths. Nevertheless, it has minor influence on the bearing deformation and column curvature (i.e., percentage changes of the responses are within 5%), regardless of the liquefiable or nonliquefiable scenario under the low or high seismic design level. As for the pile curvature, the hydrodynamic effect under the low seismic design level may remarkably increase the response by as large as 15%–20%, whereas under the high seismic design level, it has ignorable influence on the pile curvature.

Sign in / Sign up

Export Citation Format

Share Document