Laboratory Fatigue Evaluation of a Full Scale Steel Orthotropic Bridge Deck with Round Bottom Ribs and Fitted Floor Beams PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Laboratory Fatigue Evaluation of a Full Scale Steel Orthotropic Bridge Deck with Round Bottom Ribs and Fitted Floor Beams PDF full book. Access full book title Laboratory Fatigue Evaluation of a Full Scale Steel Orthotropic Bridge Deck with Round Bottom Ribs and Fitted Floor Beams by Soham Mukherjee. Download full books in PDF and EPUB format.
Author: Soham Mukherjee Publisher: ISBN: 9781339483436 Category : Languages : en Pages : 301
Book Description
The fatigue testing was run-out at 8 million cycles without any detectable fatigue cracking in the deck. The measured stress ranges at all critical connections were less than the CAFT of their respective detail categories. The test results would indicate infinite life performance of the rib-to-floor beam connection detail of the proposed deck design, as long as the site specific overloads do not exceed the AASHTO Fatigue I limit state load more than 1 in 10000 occurrences. The test results also demonstrated that the large deviation from the specified fabrication tolerances and the rejected welding procedures, which were noted during the specimen fabrication and installation, did not affect the fatigue resistance of the connection details. This suggests that the specified fabrication tolerances are arbitrary. In addition, the study provided critical information on issues related to fabrication and installation of the proposed orthotropic deck design for the lift bridge.
Author: Soham Mukherjee Publisher: ISBN: 9781339483436 Category : Languages : en Pages : 301
Book Description
The fatigue testing was run-out at 8 million cycles without any detectable fatigue cracking in the deck. The measured stress ranges at all critical connections were less than the CAFT of their respective detail categories. The test results would indicate infinite life performance of the rib-to-floor beam connection detail of the proposed deck design, as long as the site specific overloads do not exceed the AASHTO Fatigue I limit state load more than 1 in 10000 occurrences. The test results also demonstrated that the large deviation from the specified fabrication tolerances and the rejected welding procedures, which were noted during the specimen fabrication and installation, did not affect the fatigue resistance of the connection details. This suggests that the specified fabrication tolerances are arbitrary. In addition, the study provided critical information on issues related to fabrication and installation of the proposed orthotropic deck design for the lift bridge.
Author: Jayne Marks Publisher: ISBN: Category : Structural engineering Languages : en Pages : 114
Book Description
The steel orthotropic bridge deck (SOBD) is a bridge deck system which consists of longitudinal open or closed ribs that pass through transverse floor beams with a continuous steel deck plate on top. All of these components are joined using welded connections which can be costly to fabricate and prone to fatigue cracks. The rib-to-floor beam (RFB) connection in an SOBD is labor intensive and fatigue sensitive. In the past, the RFB connection has either been a fully fitted connection or a connection with an extended cut-out which is larger than the opening in the floor beam web for the rib to pass through. A third RFB detail that includes an additional opening below the rib bottom, which is not an extension of the rib opening, has been proposed and is studied herein. This connection, termed a "slit RFB connection," is similar to the fitted connection with closed, U-shaped ribs passing continuously through matching openings in the floor beam webs, but an additional opening contained entirely within the floor beam web allows for relatively unrestrained out-of-plane rib rotation. The slit RFB connection has not been used or studied previously, and shows potential for efficient, automated fabrication and good fatigue performance.
Author: Timothy Russell Gurney Publisher: Bernan Press(PA) ISBN: Category : Bridges Languages : en Pages : 176
Book Description
A broadly-based research programme on orthotropic steel bridge decks, led by D.E. Nunn, was carried out between 1963 and 1987 covering traffic usage, surfacing and fatigue. Initially the work was predictive, determining the main variables and establishing the basis of a fatigue assessment methods. Following the discovery of fatigue cracks in service, methods of repair and strengthening were developed. This work has been recorded in internal reports, but much of it has not been generally available until publication of this review. Experimental results are presented and recommendations given for the fatigue classification of welded joints in orthotropic decks.
Author: Hyoung-Bo Sim Publisher: ISBN: 9781124010908 Category : Languages : en Pages : 414
Book Description
Orthotropic steel bridge decks have been widely used for long- and medium-span bridges due to excellent structural characteristics. However, orthotropic decks have experienced various fatigue problems, resulting from high cyclic stresses in conjunction with inadequate welding details. In particular, crack at rib-to-deck welded joints due to wheel load is a concern because inspection and repair of the back side of this weld for closed ribs is not practical due to lack of access. Fatigue resistance of rib-to-deck joints can be significantly influenced by fabrication effects including weld melt-through and distortion control measures (for example, precambering and heat-straightening). Current design practice is to use empirical approach for fatigue safety assessments by conforming to the detailing requirements [for example, at least 80% partial-joint-penetration (PJP) weld at the rib-to-deck joint]. However, little experimental and analytical research has been done as to the code-specified requirements and fabrication procedure effects on the fatigue resistance of the PJP joint. Six 2-span, full-scale orthotropic steel deck specimens (10 m long by 3 m wide) were fabricated and subjected to 8 million loading cycles to study the effects of both weld melt-through and distortion control measures on the fatigue resistance of the PJP joint. Test results showed that six cracks initiated from the weld toe outside the closed rib. Only one crack developed at the weld root inside the rib; this crack initiated from a location transitioning from the 80% PJP to 100% penetration. Weld melt-through appeared to be detrimental in fatigue resistance. Precambering was beneficial as two effectively precambered specimens did not experience cracking in the PJP welds. Finite element analysis using effective notch stress method showed a good correlation with the observed crack pattern in testing. Bending stresses were dominant at the PJP joint ; shear and membrane stresses were very small. Parametric study showed that the fatigue resistance of the PJP joint can be significantly influenced by transverse loading location, deck plate thickness, and weld penetration ratio. Increasing the deck plate thickness was efficient in reducing the stresses, while the rib plate thickness had a little effect. Shallower weld penetration at the PJP joint appeared to have a positive effect in enhancing the fatigue resistance.
Author: Mark Douglas Bowman Publisher: Transportation Research Board ISBN: 030925826X Category : Technology & Engineering Languages : en Pages : 125
Book Description
"TRB's National Cooperative Highway Research Program (NCHRP) Report 721: Fatigue Evaluation of Steel Bridges provides proposed revisions to Section 7--Fatigue Evaluation of Steel Bridges of the American Association of State Highway and Transportation Officials Manual for Bridge Evaluation with detailed examples of the application of the proposed revisions."--Publisher's description.
Author: Björn Åkesson Publisher: CRC Press ISBN: 0203847768 Category : Technology & Engineering Languages : en Pages : 170
Book Description
Many old riveted railway bridges are replaced too soon due to a general lack of knowledge about the expected life span. This indicates the need for more information on fatigue and brittle fracture of riveted bridges. This book unveils extensive research and literature results on riveted bridges' fatigue live and shows how to take fatigue properly i
Author: Nirab Kumar Manandhar Publisher: ISBN: 9781303479137 Category : Languages : en Pages : 360
Book Description
The fatigue performance of the refurbished deck was evaluated by full size prototype testing of the modified Phase 1 specimen, where the intermediate floor beam was replaced to incorporate the improved design. The deck was instrumented to evaluate its response, with majority of the instrumentation concentrated around the critical welded details in the intermediate subfloor beam.
Author: Soham Mukherjee
Author: Soham Mukherjee
Author: Jayne Marks
Author: C. Beales
Author: Timothy Russell Gurney
Author: Hyoung-Bo Sim
Author: Mark Douglas Bowman
Author: Transport and Road Research Laboratory
Author: Björn Åkesson
Author: Chung-Che Chou
Author: Nirab Kumar Manandhar