RECENT RESEARCH DEVELOPMENTS IN DUCTILE FRACTURE OF STEEL BRIDGE STRUCTURES

2013 ◽  
Vol 07 (03) ◽  
pp. 1350021 ◽  
Author(s):  
HANBIN GE ◽  
LAN KANG ◽  
KEI HAYAMI
Keyword(s):  
Ductile Fracture ◽  
Seismic Design ◽  
Fracture Behavior ◽  
Damage Index ◽  
Evaluation Methods ◽  
Steel Bridge ◽  
Loading History ◽  
Section Shape ◽  
Weld Defect ◽  
Bridge Structures

Results from 23 cyclic tests, including 18 cantilever-typed steel bridge piers and five beam-to-column connections, are presented to investigate their ductile fracture behavior as related to the seismic design of steel bridge structures, and based on shell and fiber models, two evaluation methods of ductile crack initiation are proposed. The effect of various parameters, including plate width-thickness and column slenderness ratios, cross-section shape, loading history, repeated earthquakes and initial weld defect is investigated experimentally. Among these parameters, width-thickness ratio, loading history and initial weld defect are shown to have significant influence on ductile fracture behavior. The test data suggest that for unstiffened box specimens, current seismic design provision limits on ultimate strain may not provide sufficient ductility for seismic design. On the other hand, based on the experimental results, two damage index-based evaluation methods respectively using shell model and fiber model are successfully employed to predict ductile fracture of steel bridge structures. Comparisons between experimental and analytical results show that they can predict ductile fracture behavior with good accuracy across the specimen geometries, steel types, loading histories and initial weld defects.

A PERFORMANCE-BASED SEISMIC DESIGN METHODOLOGY FOR STEEL BRIDGE SYSTEMS

2009 ◽  
Vol 03 (03) ◽  
pp. 175-193 ◽  
Author(s):  
TSUTOMU USAMI ◽  
HANBIN GE
Keyword(s):  
Seismic Design ◽  
Design Methodology ◽  
Evaluation Method ◽  
Ultimate Strain ◽  
Steel Bridge ◽  
Performance Matrix ◽  
Bridge Structures ◽  
Performance Based Seismic Design ◽  
Displacement Based ◽  
A Performance

This paper outlines a performance-based seismic design methodology for steel bridge systems. Two kinds of menus are proposed. The first is the displacement-based evaluation method which compares the response displacement with the ultimate displacement, and the second is the strain-based evaluation method which compares the response strain and the ultimate strain. Moreover, the seismic required performance matrix for bridge structures and soundness matrix for members are presented and discussed.

Dual Mode Sensing of Crack Growth in Steel Bridge Structures

2012 ◽  
Author(s):  
Lingyu Yu ◽  
Liuxian Zhao ◽  
Zhenhua Tian ◽  
Victor Giurgiutiu ◽  
Paul Ziehl
Keyword(s):  
Crack Growth ◽  
Damage Index ◽  
Fatigue Cracking ◽  
Fatigue Loading ◽  
Compact Tension ◽  
Crack Growth Behavior ◽  
Steel Bridge ◽  
Dual Mode ◽  
Laboratory Setup ◽  
Bridge Structures

Monitoring of fatigue cracking in steel bridge structures using a combined passive and active scheme has been approached by the authors. Passive acoustic emission (AE) monitoring is able to detect crack growth behavior by picking up the stress waves resulting from the breathing of cracks while active ultrasonic pulsing can quantitatively assess structural defect by sensing out an interrogating pulse and receiving the structural reflections. The dual-mode sensing functionality is pursued by using the R15I ultrasonic transducers. In the paper, we presented the subject dual-mode sensing on steel compact tension (CT) specimens in a laboratory setup. Passive AE sensing was performed during fatigue loading and showed its capability to detect crack growth and location. At selected intervals of loading cycles, the test was paused to allow for active sensing by pulsing the transducers in a round-robin pattern. Plate waves were excited, propagated and interacted within the structure. Several approaches were proposed to analyze the interrogation data and to correlate the data features with crack growth. Root means square deviation (RMSD) damage index (DI) was found as a good indicator for indicating the overall crack development. Short time Fourier transform (STFT) provided both time and frequency information at the same time. Moreover, wave velocity analysis showed interesting results when crack developed across the transmitter-receiver path.

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.

Effect of Flaw Dimensions on Ductile Fracture Behavior of Non-Aligned Multiple Flaws in a Plate

2011 ◽  
Author(s):  
Katsumasa Miyazaki ◽  
Kunio Hasegawa ◽  
Koichi Saito
Keyword(s):  
Ductile Fracture ◽  
Flat Plate ◽  
Fracture Behavior ◽  
Maximum Load ◽  
Surface Flaws ◽  
Fracture Tests ◽  
The Difference ◽  
Almost All ◽  
Maximum Minimum

The fitness-for-service codes require the characterization of non-aligned multiple flaws for flaw evaluation, which is performed using a flaw proximity rule. Worldwide, almost all such codes provide their own proximity rule, often with unclear technical bases of the application of proximity rule to ductile or fully plastic fracture. In particular, the effect of flaw dimensions of multiple surface flaws on fully plastic fracture of non-aligned multiple flaws had not been clear. To clarify the effect of the difference of part through-wall and through-wall flaws on the behavior of fully plastic fracture, the fracture tests of flat plate specimens with non-aligned multiple part through-wall flaws were conducted. When the flaw depth a was shallow with 0.4 in ratio of a to thickness t, the maximum load Pmax occurred at penetration of multiple flaws and the effect of vertical distance of non-aligned multiple flaws H on Pmax was not so significant. However, when flaw depth was deep with 0.8 in a/t, Pmax occurred after penetration of flaws and the effect of H on Pmax could be seen clearly. It was judged that the through-wall flaw tests were appropriate for discussion of the effect of H on Pmax and the alignment rule of multiple flaws. In addition, in order to clarify the appropriate length parameter to estimate Pmax of test specimens with dissimilar non-aligned through-wall multiple flaws, the fracture tests of plate specimens were also conducted. The effect of different flaw length on Pmax was discussed with maximum, minimum and averages of dissimilar non-aligned multiple flaw lengths. Experimental results showed that the maximum length lmax would be an appropriate length parameter to estimate Pmax, when the non-aligned multiple through-wall flaws were dissimilar.

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.

Sign in / Sign up

Export Citation Format

Share Document