Influence of Bearing on Pier Failure Considering the Separation Condition under Near-Fault Earthquake

To study the influence of the near-fault vertical earthquake, the beam-spring-damper-pier model is used to simulate the double-span continuous beam bridge. The transient wave function expansion method and the indirect mode function method are used to calculate the seismic response of the bridge. The theoretical solutions of the contact force and displacement response of the bridge under vertical earthquake excitation near-fault are derived. By using piers with three different heights, the influence of vertical separation on pier-bending failure is analyzed reasonably. The results show that under the near-fault earthquake action, the split has a certain influence on the pier failure. Moreover, the stiffness and damping of the bearing have an influence on the pier failure, and the change of the maximum pier height has different effects. Therefore, for bridges of different sizes, it is of great significance to select the appropriate stiffness and damping bearings to reduce pier failure.

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Near-Fault Seismic Response Analysis of Bridges Considering Girder Impact and Pier Size

Mathematics ◽

10.3390/math9070704 ◽

2021 ◽

Vol 9 (7) ◽

pp. 704

Author(s):

Wenjun An ◽

Guquan Song ◽

Shutong Chen

Keyword(s):

Seismic Response ◽

Bending Moment ◽

Expansion Method ◽

Response Analysis ◽

Seismic Action ◽

Transient Wave ◽

Cross Sectional ◽

Displacement Response ◽

Near Fault ◽

Continuous Girder Bridge

Given the influence of near-fault vertical seismic action, we established a girder-spring-damping-rod model of a double-span continuous girder bridge and used the transient wave function expansion method and indirect modal function method to calculate the seismic response of the bridge. We deduced the theoretical solution for the vertical and longitudinal contact force and displacement response of the bridge structure under the action of the near-fault vertical seismic excitation, and we analyzed the influence of the vertical separation of the bridge on the bending failure of the pier. Our results show that under the action of a near-fault vertical earthquake, pier-girder separation will significantly alter the bridge’s longitudinal displacement response, and that neglecting this separation may lead to the underestimation of the pier’s bending damage. Calculations of the bending moment at the bottom of the pier under different pier heights and cross-sectional diameters showed that the separation of the pier and the girder increases the bending moment at the pier’s base. Therefore, the reasonable design of the pier size and tensile support bearing in near-fault areas may help to reduce longitudinal damage to bridges.

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Effects of Friction Force at Movable Supports on Seismic Performance of a Continuous Beam Bridge

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.353-356.2191 ◽

2013 ◽

Vol 353-356 ◽

pp. 2191-2195

Author(s):

Chang Feng Wang ◽

Yi Jun Bao

Keyword(s):

Friction Force ◽

Seismic Performance ◽

Seismic Design ◽

Analytic Model ◽

Continuous Beam ◽

Friction Element ◽

Continuous Beam Bridge ◽

Earthquake Action ◽

Beam Bridge

The friction force at movable supports has a certain influence on the seismic performance of the continuous beam bridge, so, the friction force should be taken into account in the seismic design of the bridges. The analytic model of the continuous bridge which including the effects of friction force at movable supports was put forward, and the analysis was done with the application of friction element. Through the analysis of a certain continuous beam bridge, the results indicate that the friction force can greatly decrease the earthquake action of this continuous beam bridge. And some suggestion on the bearing selection and the anti-seismic measure were also put forward according to the analysis.

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A Study on the Restrainer for Isolated Bridge

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.243-249.5208 ◽

2011 ◽

Vol 243-249 ◽

pp. 5208-5213

Author(s):

Yong Feng Du ◽

Xiao Yu Sun

Keyword(s):

Lateral Displacement ◽

Time History ◽

Nonlinear Characteristics ◽

Isolation System ◽

Finite Element Software ◽

Continuous Beam Bridge ◽

History Analysis ◽

Isolated Bridge ◽

Isolated Bridges ◽

Beam Bridge

As a result of adopting isolated bearings, it is inevitable to increase the lateral displacement of the superstructure and the chance of girder falling. However, the shear keys that just satisfies the structural design is far from meeting the requirements of displacement of isolated bridge restrictions. On account of this, given the nonlinear characteristics of bearings and the restrainer, the authors make the study on the "damping rubber with coupling collar" restrainer, and then establish isolation system model of continuous beam bridge with finite element software named Midas. Meanwhile, the effect of the restrainer on the dynamic response of isolated bridges is presented by time-history analysis, which reveals the great value in the application of limiting displacement of isolated bridge.

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