Seismic Performance of Circular Reinforced Concrete Bridge Columns Constructed with Grade 80 Reinforcement

Seismic Performance of Circular Reinforced Concrete Bridge Columns Constructed with Grade 80 Reinforcement PDF Author: David Trejo
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ISBN:
Category :
Languages : en
Pages :

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Book Description
This project assessed the use of ASTM A706 Grade 80 reinforcing bars in reinforced concrete columns. Grade 80 is not currently allowed in reinforced concrete columns due to lack of information on the material characteristics and column performance. Six half-scale, circular columns were tested: three constructed with Grade 60 reinforcement and three constructed with Grade 80 reinforcement. Designs followed standard design methodologies used by State Highway Agencies (including AASHTO). Results indicate that columns constructed with Grade 80 reinforcement performed similar to columns constructed with conventional ASTM A706 Grade 60 reinforcement. Computational modeling was performed using OpenSees for all six columns. Results indicate that the columns constructed with Grade 80 reinforcement achieved similar resistance and displacement and curvature ductility values when compared with the reference columns constructed with Grade 60 reinforcement. The columns constructed with Grade 60 reinforcement showed larger hysteretic energy dissipation than the columns constructed with Grade 80 reinforcement.

Seismic Performance of Circular Reinforced Concrete Bridge Columns Constructed with Grade 80 Reinforcement

Seismic Performance of Circular Reinforced Concrete Bridge Columns Constructed with Grade 80 Reinforcement PDF Author: David Trejo
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
This project assessed the use of ASTM A706 Grade 80 reinforcing bars in reinforced concrete columns. Grade 80 is not currently allowed in reinforced concrete columns due to lack of information on the material characteristics and column performance. Six half-scale, circular columns were tested: three constructed with Grade 60 reinforcement and three constructed with Grade 80 reinforcement. Designs followed standard design methodologies used by State Highway Agencies (including AASHTO). Results indicate that columns constructed with Grade 80 reinforcement performed similar to columns constructed with conventional ASTM A706 Grade 60 reinforcement. Computational modeling was performed using OpenSees for all six columns. Results indicate that the columns constructed with Grade 80 reinforcement achieved similar resistance and displacement and curvature ductility values when compared with the reference columns constructed with Grade 60 reinforcement. The columns constructed with Grade 60 reinforcement showed larger hysteretic energy dissipation than the columns constructed with Grade 80 reinforcement.

Seismic Performance of Reinforced Concrete Bridge Columns Constructed with Grade 80 Reinforcement

Seismic Performance of Reinforced Concrete Bridge Columns Constructed with Grade 80 Reinforcement PDF Author: Tim B. Link
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ISBN:
Category : Columns, Concrete
Languages : en
Pages : 73

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Book Description
The research presented in this thesis assessed the use of high strength steel (HSS) reinforcement for use in reinforced concrete (RC) bridge columns. HSS is not currently allowed in reinforced concrete bridge columns due to a lack of information on the material characteristics and performance information when used in RC bridge columns. Potential benefits in construction, performance, and economics justify the need for research. This research investigated the performance of HSS (ASTM A706 Grade 80 reinforcement) embedded in half-scale RC bridge columns. Column design followed standard design methodologies used by federal and state highway agencies. Six columns were subjected to lateral cyclic loadings, three columns were constructed with Grade 60 reinforcement and three columns were constructed with Grade 80 reinforcement. Results indicate that the columns constructed with Grade 80 reinforcement achieved similar resistances and displacement ductility values when compared with the reference columns constructed with Grade 60 reinforcement. The columns constructed with Grade 60 reinforcement showed larger hysteretic energy dissipation and typically exhbitied larger curvature ductility values than the columns constructed with Grade 80 reinforcement. The effects of the longitudinal reinforcement ratio and moment-shear span ratio on column performance were similar between columns constructed with Grade 60 reinforcement and columns constructed with Grade 80 reinforcement. The results from this research present a promising step towards the implementation of Grade 80 reinforcement in the design and construction of RC bridge columns, within the bounds of the variables used in the testing program.

Seismic Performance of Circular Reinforced Concrete Bridge Columns Under Bidirectional Earthquake Loading

Seismic Performance of Circular Reinforced Concrete Bridge Columns Under Bidirectional Earthquake Loading PDF Author: Mahmoud Mohamad Hachem
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ISBN:
Category :
Languages : en
Pages : 484

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Performance of Circular Reinforced Concrete Bridge Columns Under Bidirectional Earthquake Loading

Performance of Circular Reinforced Concrete Bridge Columns Under Bidirectional Earthquake Loading PDF Author: Mahmoud M. Hachem
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ISBN:
Category : Bridges, Concrete
Languages : en
Pages : 496

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Book Description
Describes the dynamic testing of 4 circular reinforced concrete bridge columns. The specimens were divided into 2 pairs, with each pair subjected to a different ground motion. Within each pair, one specimen was subjected to one component of the ground motion, while the other was subjected to 2 components. Two analytical studies were carried out for a wide array of column heights, diameters, and axial load intensities. The columns were subjected to large suites of ground motions scaled to match on average the design response spectrum.

Seismic Performance of Circular Reinforced Concrete Columns Under Varying Axial Load

Seismic Performance of Circular Reinforced Concrete Columns Under Varying Axial Load PDF Author: Gianmario Benzoni
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ISBN:
Category : Bridges
Languages : en
Pages : 214

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Book Description
The behavior of four circular reinforced concrete bridge columns, with different axial load regimes, is investigated. The first unit was tested under constant compressive axial load corresponding to an axial load ratio of 0.35. The second specimen was subjected to a constant tensile axial force equivalent to 0.087 axial load ratio. Two specimens were tested under varying regime of axial load, ranging between the two previous load limits, in order to simulate realistic seismic conditions of outer columns of multi-column bents. Extended comparison between experimental and predicted shear response, from different current equations, is provided.

Seismic Behavior of Circular Reinforced Concrete Bridge Columns Under Combined Loading Including Torsion

Seismic Behavior of Circular Reinforced Concrete Bridge Columns Under Combined Loading Including Torsion PDF Author: Suriya Prakash Shanmugam
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ISBN:
Category : Bridges
Languages : en
Pages : 634

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Book Description
"Reinforced concrete (RC) columns of skewed and curved bridges with unequal spans and column heights can be subjected to combined loading including axial, flexure, shear, and torsion loads during earthquakes. The combination of axial loads, shear force, and flexural and torsional moments can result in complex failure modes of RC bridge columns. This study carried out experimental and analytical studies to investigate the seismic performance of circular RC columns under combined loading including torsion. The main variables considered here were (i) the ratio of torsion-to-bending moment (T/M), (ii) the ratio of bending moment-to-shear (M/V) or shear span (H/D), and (iii) the level of detailing for high and moderate seismicity (high or low spiral ratio). In particular, the effects of the spiral reinforcement ratio and shear span on strength and ductility of circular RC columns under combined loading were addressed. In addition, the effects of torsional loading on the bending moment-curvature, ductility, and energy dissipation characteristics were also considered. The analytical investigation examined the development of existing models for flexure and pure torsion. Interaction diagrams between bending, shear and torsional loads were established from a semi-empirical approach. A damage-based design approach for circular RC columns under combined loads was proposed by decoupling damage index models for flexure and torsion. Experimental and analytical results showed that the progression of damage was amplified by an increase in torsional moment. An increase in the transverse spiral reinforcement ratio delayed the progression of damage and changed the torsional-dominated behavior to flexural-dominated behavior under combined flexural and torsional moments"--Abstract, leaf iii.

Experimental and Computational Evaluation of Reinforced Concrete Bridge Beam-column Connections for Seismic Performance

Experimental and Computational Evaluation of Reinforced Concrete Bridge Beam-column Connections for Seismic Performance PDF Author: Clay Joshua Naito
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ISBN:
Category : Bridges, Concrete
Languages : en
Pages : 262

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Seismic Design Recommendations for Grade 80 Reinforcing Steel in Concrete Bridge Columns

Seismic Design Recommendations for Grade 80 Reinforcing Steel in Concrete Bridge Columns PDF Author: Jessica Thangjitham
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ISBN:
Category :
Languages : en
Pages : 0

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Seismic Retrofit of Circular Reinforced Concrete Bridge Columns

Seismic Retrofit of Circular Reinforced Concrete Bridge Columns PDF Author:
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ISBN: 9780921303152
Category :
Languages : en
Pages : 12

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Book Description
Inadequate flexural strength and ductility or shear strength of concrete bridge columns has resulted in collapse or severe damage of a number of California bridges in recent moderate earthquakes. In general, these bridges were designed prior to the new seismic design methods which were implemented in the mid-seventies. Bridges constructed in accordance with the new design methods have performed well in recent earthquakes. However, the large number of older bridges that are in service, particularly freeway overpasses designed and constructed in the 1950s and 1970s, are now recognized to have substandard design details and to constitute a cause for major concern. This paper reports the results of a theoretical and experimental program investigating retrofit techniques for circular columns by encasing the critical regions within a steel jacket. The jacket is bonded to the column using grout. Results from six large-scale column tests show that the casing acts efficiently as confinement reinforcement, enabling a displacement ductility factor of greater than 6 to be achieved. The casing also inhibits bond failures at the laps of longitudinal reinforcement in the critical regions of the column by restraining the dilation and spalling of the cover concrete which degenerates into bond failure. Comparisons of 'as-built' and retrofitted columns are presented, and experimental strengths and ductilities are compared with analytical predictions. For the covering abstract of the Conference see IRRD Abstract no. 807839.

Predicting Seismic Performance of Circular Reinforced Concrete Bridge Columns

Predicting Seismic Performance of Circular Reinforced Concrete Bridge Columns PDF Author: Hamid Anghaie
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ISBN:
Category :
Languages : en
Pages :

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Book Description
"The 2014 Canadian Highway Bridge Design Code (CHBDC) has been significantly modified to improve the seismic design and analysis of new bridges. Performance-Based Design has been implemented in the code as the main seismic design methodology for bridges. The goal of this research is to provide appropriate damage indicators that can be used in the performance-based design approach. Numerical models were developed using the Response-2000 program and the OpenSees platform. Nonlinear pushover analyses were conducted on a number of columns tested by other researchers. The numerical models were validated by comparing the predictions to the test results and the accuracy of the predictions was investigated. These studies provide guidance for engineers in the numerical modeling of bridge columns and also provide damage indicators for cover spalling, residual crack width, longitudinal bar buckling, and longitudinal bar fracture. " --