scholarly journals Estimation of Rheological Effects in Cantilever Concrete Bridges on the Basis of a Span's Deflection Line

2021 ◽  
Author(s):  
Bartosz Pisarek ◽  
Czeslaw Machelski
Keyword(s):  
Characteristic Feature ◽  
Marked Improvement ◽  
Small Extent ◽  
Concrete Bridges ◽  
Bridge Structure ◽  
Concrete Cracking ◽  
Measurement Results ◽  
Bridge Structures ◽  
Original Measurement ◽  
Internal Forces

A characteristic feature of bridges as large span objects made using cantilever concreting technology are their excessive deflections, which are a result of rheological processes in concrete and pre-stressing steel. These deflections can be caused by the destruction of the material, e.g., concrete cracking, as well as the changing of the static scheme of the bridge structure, such as the subsidence of supports. The purpose of the work is to determine internal forces based on the deformation of a span. An algorithm for the correction of the deflection function, which is determined from geodetic measurements with a low accuracy, was proposed. It is characterized by a marked improvement in the results of calculations and, to a small extent, leads to the smoothing of the original measurement results. The algorithm is adapted to the analysis of a selected fragment of the structure, e.g., spans with the largest length and can be useful for monitoring bridge structures.

scholarly journals Rheological Effects in the Bridges Constructed with Cantilever Method

2020 ◽  
Vol 9 (1) ◽  
pp. 77-93
Author(s):  
Bartosz Pisarek ◽  
Czesław Machelski
Keyword(s):  
Characteristic Feature ◽  
Cross Section ◽  
Significant Influence ◽  
Bridge Structure ◽  
Concrete Cracking ◽  
Comparative Analyses ◽  
Prestressing Steel ◽  
Geodetic Measurements ◽  
Operation Phase

Abstract A characteristic feature of bridges made using cantilever concreting technology is their excessive deflections, which are a result of rheological processes in concrete and prestressing steel. These deflections can be caused by the destruction of the material, e.g. concrete cracking, as well as the changing of the static scheme of the bridge structure, such as the subsidence of supports. The final result of a structure’s operation is changes in its grade line, which in this paper are considered as the deflection line of a bridge’s span. The purpose of the paper is to determine the participation of a structure’s rotation over supports in the deformation of the span with the largest length. The authors proposed an algorithm for determining the deflection function and rotation angles, which were obtained on the basis of changes in the curvature of the beam. It is characterised by an accurate mapping of the rheological processes that occur in the bridge, which is calculated on the basis of the changes of the grade line obtained from geodetic measurements on site. The paper proposes a general geometric indicator of the box cross-section cantilever, which is calculated for the construction phase, and a different indicator for the operation phase. They can be used for comparative analyses of various bridges. The analysis of deflections in cantilever bridges during the operation phase of their longest spans indicates that there is a significant influence of the angles of rotation over the supports. In the paper, such a group of bridges is qualified as unstable, in which the static scheme changes from a determinate cantilever state (the construction phase) into a multi-span system with different span lengths (the operation phase).

scholarly journals Designing of support zones of concrete bridges to withstand action of static and dynamic load

2010 ◽  
Vol 8 (2) ◽  
pp. 235-246
Author(s):  
Milan Gligorijevic ◽  
Slavko Zdravkovic ◽  
Marija Spasojevic-Surdilovic
Keyword(s):  
Dynamic Load ◽  
Great Influence ◽  
Concrete Bridges ◽  
Bridge Structure ◽  
Small Probability ◽  
Expansion Joints ◽  
Engineering Structure ◽  
Bridge Structures ◽  
Weak Points

In the paper are presented some of the acquired experiences in designing and construction of bridge structures in several countries, with a special attention to the analysis of support zones and expansion joints behavior of a number of road bridges. During destruction or damage of bridges, there is a small probability, but still there, that the human lives might be endangered (Kobe, Japan 17th January 1995); what is likely, however, is that it will be very difficult to help the injured in the region. Considering that the characteristics of removal of supports has a great influence on the behavior of the entire bridge structure, the design of support joints and connections must be paid due attention. In the recent decades, efforts are made to enhance research of all engineering structure, and thus the bridge structures and their weak points.

scholarly journals Review of annual progress of bridge engineering in 2019

2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Renda Zhao ◽  
Yuan Yuan ◽  
Xing Wei ◽  
Ruili Shen ◽  
Kaifeng Zheng ◽  
...  
Keyword(s):  
High Performance ◽  
Concrete Bridges ◽  
Bridge Engineering ◽  
Research Progress ◽  
Steel Bridge ◽  
Wind Resistance ◽  
Main Research ◽  
Bridge Model ◽  
Bridge Evaluation ◽  
Bridge Structures

AbstractBridge construction is one of the cores of traffic infrastructure construction. To better develop relevant bridge science, this paper introduces the main research progress in China and abroad in 2019 from 13 aspects, including concrete bridges and the high-performance materials, the latest research on steel-concrete composite girders, advances in box girder and cable-supported bridge analysis theories, advance in steel bridges, the theory of bridge evaluation and reinforcement, bridge model tests and new testing techniques, steel bridge fatigue, wind resistance of bridges, vehicle-bridge interactions, progress in seismic design of bridges, bridge hydrodynamics, bridge informatization and intelligent bridge and prefabricated concrete bridge structures.

Probabilistic Peak Displacement Analysis of Bridge Structures with P-Δ Effect

2013 ◽  
Vol 405-408 ◽  
pp. 1674-1677
Author(s):  
Bo Yu ◽  
Di Liu ◽  
Lu Feng Yang
Keyword(s):  
Time History ◽  
Dynamic Responses ◽  
Nonlinear Time History Analysis ◽  
Bridge Structure ◽  
Vibration Period ◽  
Peak Displacement ◽  
Sdof System ◽  
Bridge Structures ◽  
Performance Based Seismic Design ◽  
Nonlinear Time History

Peak displacement is one of the most important parameters for the performance based seismic design of bridge structure, while the peak displacement is often significantly impacted by the P-Δ effect. In this study, the influence of the P-Δ effect on the statistics of peak displacement of bridge structure was quantificationally investigated based on a series of nonlinear time-history analysis. The bridge structure was idealized as the single degree of freedom (SDOF) system and the hysteretic behaviour was represented by the improved Bouc-Wen model. The statistic analysis was implemented based on the inelastic dynamic responses of the SDOF system under 69 selected earthquake records. The results show that the P-Δ effect has significant impact on the mean and dispersion of peak displacement of bridge structures, especially if the normalized yield strength and the natural vibration period are small.

scholarly journals Reliability-Based Topology Optimization Using Two Alternative Inverse Optimum Safety Factor Approaches: Application to Bridge Structures

2020 ◽  
Vol 30 (3) ◽  
pp. 498-511
Author(s):  
Ghias Kharmanda ◽  
Imad R. Antypas ◽  
Alexey G. Dyachenko
Keyword(s):  
Topology Optimization ◽  
Safety Factor ◽  
Optimization Model ◽  
High Performance ◽  
Bridge Structure ◽  
Objective Performance ◽  
Bridge Structures ◽  
Alternative Approaches ◽  
Alternative Choice

Introduction. The Deterministic Topology Optimization model provides a single solution for a given design space, while the Reliability-Based Topology Optimization model provides several reliability-based topology layouts with high-performance levels. The objective of this work is to develop two strategies that can provide the designer with two categories of resulting topologies. Materials and Methods. Two alternative approaches based on the Inverse Optimum Safety Factor are developed: the first one is called the Objective-Based IOSF Approach and the second one is called Performance-Based IOSF Approach. When dealing with bridge structures, the uncertainty on the input parameters (boundary conditions, material properties, geometry, etc.) and also output parameters (compliance, etc.) should not be ignored. The sensitivity analysis is the fundamental idea of both developed approaches, identifies the role of each parameter on the structural performance. In addition, the optimization domain choice is important when eliminating material that should not affect the structure functioning. Results. Two numerical examples on a 2D bridge structure are presented to demonstrate the efficiency of the developed approaches. When considering a certain reliability level, the Reliability-Based Topology Optimization leads to two different configurations relative to the Deterministic Topology Optimization one. When increasing the reliability levels, the quantity of materials decreases that leads to an increase in the number of holes in the structures. Discussion and Conclusion. In addition to their simplified implementation, the developed alternative approaches can be considered as two generative tools to produce two different categories (families) of solutions where an alternative choice between two functions (objective/performance) is presented.

scholarly journals State-of-the-art and annual progress of bridge engineering in 2020

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Renda Zhao ◽  
Kaifeng Zheng ◽  
Xing Wei ◽  
Hongyu Jia ◽  
Haili Liao ◽  
...  
Keyword(s):  
High Performance ◽  
Concrete Bridges ◽  
Bridge Engineering ◽  
Research Progress ◽  
Concrete Bridge ◽  
Steel Bridge ◽  
Bridge Structure ◽  
Coupling Vibration ◽  
Main Research ◽  
Bridge Assessment

AbstractBridge construction is one of the cores of traffic infrastructure construction. To better develop relevant bridge science, this paper introduces the main research progress in China and abroad in 2020 from 16 aspects. The content consists of four major categories in 16 aspects. The first part is about the bridge structure, including concrete bridge and high-performance materials, steel bridges, composite girders. The second part is about the bridge disaster prevention and mitigation, including bridge seismic resistance, wind resistance of bridge, train-bridge coupling vibration research, bridge hydrodynamics, the durability of the concrete bridges, fatigue of steel bridge, temperature field and temperature effect of bridge; The third part is about the bridge analyses, including numerical simulation of bridge structure, box girder and cable-stayed bridge analysis theories. The last part is concerning the bridge emerging technologies, including bridge informatization and intelligent bridge, the technology in bridge structure test, bridge assessment and reinforcement, prefabricated concrete bridge structure.

scholarly journals Effects of Surrounding Earth on Shell During the Construction of Flexible Bridge Structures

2019 ◽  
Vol 41 (2) ◽  
pp. 67-73
Author(s):  
Czesław Machelski
Keyword(s):  
Steel Structure ◽  
Steel Structures ◽  
Static Condition ◽  
Steel Bridge ◽  
Interfacial Interactions ◽  
Soil Medium ◽  
Bridge Structures ◽  
Internal Forces ◽  
Bearing Loads ◽  
Corrugated Plates

AbstractA characteristic feature of soil-steel structures is that, unlike in typical bridges, the backfill and the carriageway pavement with its foundation play a major role in bearing loads. In the soil-steel structure model, one can distinguish two structural subsystems: the shell made of corrugated plates and the backfill with the pavement layers. The interactions between the subsystems are modelled as interfacial interactions, that is, forces normal and tangent to the surface of the shell. This is a static condition of the consistency of mutual interactions between the surrounding earth and the shell, considering that slip can arise at the interface between the subsystems. This paper presents an algorithm for determining the internal forces in the shell on the basis of the unit strains in the corrugated plates, and subsequently, the interfacial interactions. The effects of loads arising during the construction of a soil-steel bridge when, for example, construction machines drive over the structure, are taken into account in the analysis of the internal forces in the shell and in the surrounding earth. During construction, the forces in the shell are usually many times greater than the ones generated by service loads. Thus, the analytical results presented in this paper provide the basis for predicting the behaviour of the soil medium under operational loads.

Consideration of the vertical load from a tsunami on bridge structures

2021 ◽  
pp. 86-92
Author(s):  
Anton D. Yakovlev
Keyword(s):  
Natural Disaster ◽  
Russian Federation ◽  
Computer Modelling ◽  
Significant Part ◽  
Transport Infrastructure ◽  
Bridge Structure ◽  
Vertical Load ◽  
Tsunami Waves ◽  
Bridge Structures ◽  
The Russian Federation

A significant part of the territory of the Russian Federation is exposed to various natural disasters. One of the most destructive are tsunami waves. At the same time, for the development of these territories, there is a need for the development of transport infrastructure, which implies, among other things, the design of bridges. To ensure the reliability of bridges in the event of tsunami, it is necessary to fully take into account the possible impacts from these waves. In Russia, there is a document to determine the load from the tsunami. But, despite the existence of this document, the issue of taking into account the loads from the tsunami on various structures remains relevant. In particular, there are no clear guidelines for accounting for vertical loads from tsunami waves on bridge structures. With the help of the studies carried out on computer modelling of the wave roll-up on the bridge structure, this article proves the need to take into account the vertical loads from the tsunami, and also proposes a method for determining its numerical values. This study can complement the basic methodology for determining the loads from tsunami waves on bridge structures and help designers fully account for this dangerous natural disaster.

Fire of steel and composite beam bridges

2019 ◽  
Author(s):  
Henryk Zobel ◽  
Wojciech Karwowski ◽  
Agnieszka Golubińska ◽  
Thakaa Al-Khafaji
Keyword(s):  
Fire Resistance ◽  
Composite Beam ◽  
Structural Integrity ◽  
Bridge Structure ◽  
Long Span ◽  
Long Span Bridge ◽  
Bridge Structures ◽  
Fire Scenarios ◽  
Design Construction ◽  
Cable Stayed Bridges

<p>The problem of bridge fires is growing. Because of a bad experience in Poland, it was decided to improve fire resistance of long span bridge structures, and of cable-stayed bridges in particular. Statistics shows that fire is a real threat to this kind of structure. They also confirm that the worst results of fire are for those with an orthotropic deck rather than with a concrete one. The basic problems to solve are how to predict fire resistance of a particular bridge and how to ensure safety and structural integrity of the bridge structure. Taking into account the fact that bridge standards do not include information relating to fire protection, and fire standards do not determine rules for design, construction and maintenance of such structures, there are no regulations for this problem. Fire scenarios are devoted to buildings, but the thermo-structural behavior of bridges is different.</p>

Numerical and Experimental Assessment of the Highway Arch Viaduct

2015 ◽  
Vol 769 ◽  
pp. 252-259
Author(s):  
Jan Bencat ◽  
Maria Stehlikova ◽  
Milan Skarupa
Keyword(s):  
Dynamic Testing ◽  
Highway Bridges ◽  
Structural Condition ◽  
Traffic Load ◽  
Analytical Models ◽  
Mode Shapes ◽  
Bridge Structure ◽  
Modal Damping ◽  
Bridge Structures ◽  
And Performance

Full–scale dynamic testing of bridge structures can provide valuable information on the service behavior and performance of structures. With the growing interest in the structural condition of highway bridges, dynamic testing can be used as a tool for assessing the integrity of bridges. From the measured dynamic response, induced by instructed passing trucks, modal parameters (natural frequencies, mode shapes and modal damping values) and system parameters (stiffness, mass and damping matrices) are obtained. These identified parameters can then be used to characterize and monitor the service of the bridge structure in the future. Analytical models of the structure can also be validated using these parameters [1,2]. The paper presents a procedure for estimating the traffic load bearing capacity of the steel arch highway viaduct Bridge Structure 205 (DC1–9, 755 m) constructed on Highway D1 in Nord Slovakia (Fig. 1) over the natural hollow basin via dynamic tests of the viaduct structures.

Sign in / Sign up

Export Citation Format

Share Document