Study on the Effects of Train Live Loads on Isolated and Non-Isolated Simply Supported Railway Bridges

2011 ◽  
Vol 50-51 ◽  
pp. 100-104
Author(s):  
Chang Yong Zhang ◽  
Tie Yi Zhong ◽  
Ke Jian Chen ◽  
Yun Kang Gong
Keyword(s):  
Time History ◽  
Railway Bridge ◽  
Finite Element Program ◽  
Railway Bridges ◽  
Simply Supported ◽  
Rubber Bearing ◽  
Lead Rubber Bearing ◽  
Element Program ◽  
Live Loads ◽  
High Level

In this paper, based on the finite element program ANSYS, the model of a simply supported railway bridge with and without isolation using lead rubber bearing is established. Seismic response time-history analyses of the bridge subjected to high-level earthquakes are carried out considering and not considering train live loads. Through the comparison and analyses of the results, the effects of train live loads on seismic calculation of non-isolated railway bridges and isolated railway bridges are obtained. The results of the research will support the further study on seismic design and isolation design of simply supported railway bridges.

Elasto-Plastic Earthquake Response Analysis of High-Speed Railway Bridge Fabricated Isolation Bearings

2011 ◽  
Vol 675-677 ◽  
pp. 1175-1178
Author(s):  
Ling Kun Chen ◽  
Li Zhong Jiang ◽  
Peng Liu
Keyword(s):  
High Speed ◽  
Plastic Hinge ◽  
Response Analysis ◽  
Railway Bridge ◽  
High Speed Railway ◽  
Finite Element Program ◽  
Railway Bridges ◽  
Earthquake Resistant ◽  
Element Program ◽  
Rubber Bearings

Basin rubber bearings are frequently used in high-speed railway bridge or passenger special line railway bridge, lead rubber bearings (LRB) are infrequently used in those railway bridges nowdays, the study on earthquake-resistant capability of railway bridge fabricated isolation bearing - the intelligent and functional structure - would be beneficial in engineering practices. Elasto-plastic earthquake responses of high-speed railway bridges fabricated LRB are studied by means of the finite element program, earthquake responses of railway bridges under high-speed vehicles and different earthquake action fabricated and unfabricated isolation bearing are calculated respectively. The results show that: plastic hinge will develop at the bottom of piers in regard to railway bridges with mid-high and low pier; LRB can reduce displacement and inner forces of structures and improve earthquake-resistant capability of structures effectively.

scholarly journals The Behavior of Elevated Water Tanks under Impact Loading

2021 ◽  
Author(s):  
Davoud Tavakoli ◽  
Ali Ahmadi
Keyword(s):  
Impact Load ◽  
Water Structure ◽  
Blast Loading ◽  
Structural Behavior ◽  
Finite Element Program ◽  
Rubber Bearing ◽  
Lead Rubber Bearing ◽  
Element Program ◽  
Elevated Water ◽  
Water Tanks

Because of the crucial role of elevated water tanks and their various uses, it is necessary to evaluate their structural behavior under threats to improve the durability performance of such tanks without putting them in jeopardy. In the present research, three open cylindrical concrete water tanks were modeled under an impact load (aerial blast) with the weight of 100 kg TNT explosive charge. The tanks were modeled in 3 forms: slender, middle, and broad (Aspect ratio = 1.28,1 and 0.85). Each tank contained various levels of water (non-water, half water, and full water) to estimate their structural behavior under blast loading. Moreover, the CEL (Coupled Eulerian-Lagrangian) approach was used to simulate water structure interaction in finite element program. For a comprehensive analysis of the structural behavior of water tanks, LRB (Lead rubber bearing) isolator device was also used to observe the effect of isolator under blast loading on elevated water tanks in all models. The results of this study show that the water level leads to stiffness of the structures that cause better performance under blast loading and also the intersection of the shaft and concrete column would be the critical section of this structure under blast loading. It is also concluded that Stress and Strain decrease as the water tanks level increase and stiffen (up to 33 %). Also, it is noticeable that the existence of the isolator has deteriorated the results because of the decreases in the structure’s stiffness and the increase of the displacements.

Seismic performance of Greater Jakarta LRT with added lead rubber bearing using non-linear time history analysis

2021 ◽  
Author(s):  
Iswandi Imran ◽  
Marie Hamidah ◽  
Tri Suryadi ◽  
Hasan Al-Harris ◽  
Syamsul Hidayat
Keyword(s):  
Linear Time ◽  
Time History ◽  
Time History Analysis ◽  
Performance Level ◽  
Structural Performance ◽  
Isolation System ◽  
Rubber Bearing ◽  
Lead Rubber Bearing ◽  
History Analysis ◽  
Seismic System

<p>In order to overcome stringent seismic requirement in the new Greater Jakarta Light Rail Transit Project, a breakthrough seismic system shall be chosen to obtain expected structural performance. This seismic system shall be designed to provide operational performance level after strong earthquake events. To achieve the criteria, seismic isolation system using Lead Rubber Bearings is chosen. With this isolation system, Greater Jakarta LRT has become the first seismically isolated infrastructure and apparently an infrastructure with the largest numbers of LRBs in one single project in Indonesia. More than 10.400 Pcs LRBs are used for the first phase of the construction and the numbers will be certainly increased in the next phase of the construction. To evaluate the structural performance, non-linear time history analysis is used. A total of 3 pair matched ground motions will be used as the input for the response history analysis. The ability of the lead rubber bearing to isolate and dissipate earthquake actions will determine its structural performance level. This will be represented by the nonlinear hysteretic curves obtained throughout the earthquake actions.</p>

scholarly journals A comparative study of base isolation devices in light rail transit structure featured with lead rubber bearing and friction pendulum system

2018 ◽  
Vol 195 ◽  
pp. 02013
Author(s):  
Santi Nuraini ◽  
Asdam Tambusay ◽  
Priyo Suprobo
Keyword(s):  
Seismic Isolation ◽  
Time History ◽  
Light Rail ◽  
Rail Transit ◽  
Light Rail Transit ◽  
Pendulum System ◽  
Rubber Bearing ◽  
Lead Rubber Bearing ◽  
Friction Pendulum ◽  
Friction Pendulum System

Advanced nonlinear analysis in light rail transit (LRT) structures has been undertaken to examine the influence of seismic isolation devices for reducing seismic demand. The study employed the use of two types of commercially available bearings, namely lead rubber bearing (LRB) and friction pendulum system (FPS). Six LRT structures, designed to be built in Surabaya, were modelled using computer-aided software SAP2000, where each of the three structures consisted of three types of LRB and FPS placed onto the pier cap to support the horizontal upper-structural member. Nonlinear static pushover and dynamic time history analysis with seven improved ground motion data was performed to gain improved insights on the behavioural response of LRT structures, allowing one to fully understand the supremacy of seismic isolations for protecting the structure against seismic actions. It is shown that both devices manage to isolate seismic forces, resulting in alleviation of excessive base shear occurring at the column. In addition, it is noticeable that the overall responses of LRB and FPS shows marginal discrepancies, suggesting both devices are interchangeable to be used for LRT-like structures.

scholarly journals Response of a C-Shaped Building Under Blast Loadings

2019 ◽  
Vol 8 (2S8) ◽  
pp. 1012-1016
Keyword(s):  
Comparative Study ◽  
Research Work ◽  
Blast Load ◽  
Building Structures ◽  
Finite Element Program ◽  
Building Model ◽  
Element Program ◽  
Live Loads ◽  
Triangular Function ◽  
The Comparative Study

Our structures especially building structures, are designed basically for dead loads, live loads for static loading conditions and for wind, earthquake and their combinations for dynamic lateral loadings. As the structures are not designed for unexpected blast load conditions it is not possible for the structures to resist such destructive forces of blast impacts. In this research work a comparative study has been done for the blast forces and earthquake forces. For this study purpose a C-shaped building was modelled for the analysis in finite element program SAP-2000. Initially the building model was analysed for Dead loads, live loads and Earthquake loads. In the second model the building is designed for Blast load. Blast load was defined as a triangular function using codal provisions suggested by IS-4991. The results then are compared and it was checked how far a building designed for EQ can withstand a blast of specific amount of TNT. Also the effect of blast forces due to shape of the building is checked. The comparative study has been mapped and indicated in the paper.

The Influence Analysis of Mechanical Behavior between Pile and Soil on End Bearing Pile Foundation’s Dynamic Characteristic

2014 ◽  
Vol 580-583 ◽  
pp. 1481-1485
Author(s):  
Wei Hu ◽  
Ya Hui Zhang ◽  
Ying Zhang
Keyword(s):  
Mechanical Behavior ◽  
Structural Model ◽  
Ground Surface ◽  
Time History ◽  
Horizontal Displacement ◽  
Shearing Stress ◽  
Maximum Acceleration ◽  
Finite Element Program ◽  
Element Program ◽  
End Bearing Pile

Dynamic structural model of saturated soil was introduced, and combining with the finite element program, the finite-infinite element models of end bearing pile foundations was established. Four models of interface between pile and soil including absolutely jointed, slippage, crack, both slippage and crack were considered to study the interface’s effect on pile foundation’s dynamic characteristics. The results were as follows: the interface’s mechanical behavior has a little influence on the distributions of pile section’s shearing stress and horizontal displacement. Pile section’s shearing stress reaches the maximum near the ground surface when interface is slippage or crack, and reaches the minimum ones when interface is absolutely jointed. Horizontal displacement could be divided into two phases and the ground surface is the dividing line. The interface’s behavior greatly changes the distribution of acceleration time-history curve. To different models, the maximum acceleration all appears at the ground surface. On the whole, the interface’s behavior has significant influence on end bearing pile, which should be pay attention in the design from now on.

Optimization of Large-Tonnage Lead Rubber Bearing for Highway Bridge

2011 ◽  
Vol 71-78 ◽  
pp. 3832-3836
Author(s):  
Guo Hui Zhao ◽  
Jian Hui Zhao ◽  
Xin Zhang
Keyword(s):  
Energy Dissipation ◽  
Axial Compression ◽  
Compression Ratio ◽  
Great Influence ◽  
Time History ◽  
Soil Conditions ◽  
Axial Compression Ratio ◽  
Rubber Bearing ◽  
Lead Rubber Bearing ◽  
Isolated Bridge

A 10000kN lead rubber bearing is taken as an example to study the energy dissipation mode of isolated bridge and optimal lead rate of the bearing. Bilinear spring model considering the effect of real lead rate on the stiffness is used to simulate the bearing. Optimization of the lead rate in different site soil conditions and different axial compression ratio of pier is carried on by using nonlinear dynamic time history analysis. It is shown that the axial compression ratio of pier has great influence on the energy dissipation mode of isolated bridge and the optimal lead rate of the bearing. Site soil conditions have little effect on the energy dissipation mode of the isolation bridge and the optimal lead rate when the axial compression ratio of pier is fixed.

scholarly journals Link Slab Capacity In Bridges Supported By Lead Rubber Bearing And Elastomer

2019 ◽  
Vol 24 (2) ◽  
pp. 73
Author(s):  
Inas Novikasari ◽  
Anis Rosyidah
Keyword(s):  
Seismic Isolation ◽  
Design Criteria ◽  
Isolation System ◽  
Expansion Joints ◽  
Debris Accumulation ◽  
Seismic Isolator ◽  
Rubber Bearing ◽  
Lead Rubber Bearing ◽  
Seismic Force ◽  
High Level

Debris accumulation in bridge slab gaps which use expansion joints can restrain deck expansion, causing undesirable forces on floor deck and damage to the structure. In order to avoid the worst possibility that can occur, an alternative using link slab is utilized. The use of link slab at high level seismic force location, requires the Seismic Isolation System on bridge to reduce the seismic force. The application of Seismic Isolation System can be conducted by Lead Rubber Bearing (LRB) type of seismic isolator. This study compares the use of Lead Rubber Bearing (LRB) and elastomer on bridge link slabs against the dimension of the link slab. In this study structural modeling used 2 models: bridges supported by elastomer and bridges supported by LRB with software-made. The link slab analysis approach used were analytical methods or classical methods. Based on results of the analysis, the width of the crack that occured on bridge supported by LRB is 0.218 mm while on the bridge supported by elastomer is 0.269 mm. The use of Lead Rubber Bearing (LRB) type of support will give more advantages to the design of the link slab since it results in smaller crack design criteria.

Time-History Analysis of the High-Rise Building Structure Based on ANSYS

2011 ◽  
Vol 71-78 ◽  
pp. 2836-2839
Author(s):  
Hui Xia Xiong ◽  
Chang Yong Wang
Keyword(s):  
Structural Design ◽  
Time History ◽  
Time History Analysis ◽  
Building Structure ◽  
Finite Element Program ◽  
High Rise ◽  
High Rise Building ◽  
History Analysis ◽  
Earthquake Load ◽  
Element Program

The dynamic property of a high-rise building structure and time-history analysis under earthquake were analyzed by using the finite element program ANSYS. A modal analysis of the tower was conducted and the first 20 frequencies and modal shapes were obtained. The displacements and inner force under the earthquake were calculated. The result showed that the structural stiffness was enough to sustain earthquake load; and the stiffness distributed equally. These results can provide reliable basis for structural design.

Preliminary Evaluation of the Bump at the End of the Railway Bridge

2007 ◽  
Author(s):  
Jennifer E. Nicks ◽  
Jean-Louis Briaud
Keyword(s):  
Preliminary Evaluation ◽  
Railway Bridge ◽  
Safety Hazards ◽  
Finite Element Program ◽  
Entire Study ◽  
Railroad Bridges ◽  
Approach Slabs ◽  
Impact Forces ◽  
Element Program ◽  
Railroad Company

Bumps often develop at the interface between the bridge deck and the approach embankment of a railway bridge. The differential track movement at this transition zone creates higher impact loads, reduced bridge and embankment life, possible safety hazards, and higher maintenance costs. This study investigates the extent of the problem, typical maintenance expense, reasons behind the bump, and possible solutions. Based on a survey conducted to evaluate current practice, the bump problem affects about 50% of all railroad bridges and costs each railroad company an estimated $2,550,000 on maintenance. The typical slope for current bumps is equal to approximately 1:150. Using LS-DYNA, a 3-D, non-linear finite element program, a simple, rigid system was simulated to find the range of impact forces resulting from different bump slopes. A parametric study will be conducted in the future to examine the components involved and to optimize various solutions, such as approach slabs. The results from the entire study will help to minimize the bump at the end of the railway bridge.

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