Field Load Rating and Grillage Analysis Method for Skewed Steel Girder Highway Bridges

2021 ◽  
Vol 26 (11) ◽  
pp. 05021013
Author(s):  
Renxiang Lu ◽  
Johnn Judd ◽  
Michael Barker
Author(s):  
Naoto Yoshida ◽  
Masahiro Sakano ◽  
Hideyuki Konishi ◽  
Takashi Fujii

Fatigue cracking in steel girder web penetration details is so dangerous that it can break steel girders. A one-meter-long crack was detected in Yamazoe Bridge in 2006. Since a number of highway bridges with such web penetration details may exist in Japan, it is of urgent importance to understand these fatigue-strength properties. However, few fatigue tests have been reported on steel girder web penetration details. The purpose of this study is to clarify fatigue behavior of steel girder web penetration details with a slit through fatigue tests of specimens with these details. We designed and fabricated girder specimens that have steel girder web penetration details, in which cross-beam bottom flanges are connected to each top or bottom surface of a slit by welding. First, we conducted static loading tests to understand the stress distributions around web penetration details. Second, we conducted fatigue tests to examine fatigue crack initiation and propagation behavior and fatigue strength.


Author(s):  
Chihiro Sakamoto ◽  
Masahiro Sakano ◽  
Hideyuki Konishi ◽  
Takashi Fujii

Fatigue cracking in steel girder web penetration details is so dangerous that it can break steel girders. Since a number of highway bridges have such web penetration details in Japan, it is of urgent importance to grasp these fatigue strength properties. In this study, we investigate stress reduction effects of three face attachment retrofit through fatigue tests using a large girder specimen with web penetration details where cross beam lower flanges are connected to the lower surface of a slot by welding. As a result, there is very little difference between two and three face attachments about stress reduction effects, while they are more effective than one face attachment. The upper side attachment is more effective than the lower side attachment, while both side attachment is best. Two and three face both side attachments can reduce about 40% of stress concentration, while two and three face upper side attachments can reduce 50– 60%.


Author(s):  
Chihiro Sakamoto ◽  
Masahiro Sakano ◽  
Hideyuki Konishi ◽  
Takashi Fujii

Fatigue cracking in steel girder web penetration details is so dangerous that it can break steel girders. Since a number of highway bridges have such web penetration details in Japan, it is of urgent importance to grasp these fatigue strength properties and develop effective retrofitting methods. In a previous report, we investigated the stress distributions around web penetration details, and fatigue cracking behavior, using steel girder specimens with web penetration details. In this study, we investigate effects of retrofitting methods against fatigue cracking in web penetration details through fatigue tests using large girder specimens with web penetration details in which cross beam lower flanges are connected to lower surface of a slot by welding. Principal results obtained through this study are as follows: (1) Weld toe grinding can extend fatigue life more than 5 times, (2) Two-face attachment can extend fatigue life more than 10 times, and (3) Two-face attachment with weld toe grinding can extend fatigue life more than 25 times.


Author(s):  
Leila Zahedi ◽  
Ming Lu

A novel labour-hour budgeting methodology is proposed by integrating productivity concepts in project scheduling and budgeting to enhance the accuracy of labour cost budgeting for planning labour-intensive projects. The proposed methodology applies discrete event simulation approach to represent crew formation, labour resource utilization and labour resource flowing between consecutive activities, which allows for quantitatively characterizing the impact of labour semi-productive time on labour cost budgeting as a time-dependent variable. Simulation-based assessment of variations in crew sizes and labour allocations is conducive to reducing semi-productive time and thus enhancing the cost performance of the whole project. The proposed methodology is then applied in a real-world case study for planning steel girder fabrication projects in construction of highway bridges. Not limited to budgeting for labour resources in construction-oriented fabrication facility, the research contributions are also significant to other construction planning settings where limited resources are shared and utilized among different activities.


2021 ◽  
Author(s):  
Achraf Ben Afia ◽  
Charles-Darwin Annan ◽  
Pampa Dey

<p>Aluminium as a structural material is known for its lightweight, which facilitates easy transportation and installation, and reduces foundation requirements. However, this lightweight characteristic makes it sensitive to excitations from vehicular traffic leading to dominating dynamic design over the static one. The dynamic design of highway bridges by the Canadian Highway Bridge Design Code (CSA S6-19) is based on the concept of equivalent dynamic amplification factors (DAF), which were derived largely based on the observations from bridges constructed with traditional materials such as concrete, wood and steel. It is prudent to evaluate whether these factors are applicable to lightweight bridges made with extruded aluminium decks. In addition, since road roughness plays an important role in the dynamic behaviour of a bridge, it is important to consider the influence of roughness on the bridge vibration response. The objective of this research is to investigate the dynamic behaviour of aluminium deck-on-steel girder bridges under vehicular loads considering the effect of road roughness, and consequently evaluate the applicability of the current design DAFs for such structures. For this purpose, numerical models have been developed in Abaqus for a range of selected bridge configurations and loading parameters and subsequently the key observations and conclusions from the numerical analysis have been presented in this paper.</p>


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