Author: AG. Vlassis
Publisher:
ISBN:
Category : Bridges
Languages : en
Pages : 10
Book Description
A specimen consisting of two box girder reinforced concrete blocks representing the adjacent spans of a reference bridge at an in-span hinge was constructed and tested under incrementally increasing input excitation to investigate the impact between adjacent bridge spans at in-span hinges, to evaluate the efficacy of restrainers in reducing relative displacements across the hinges, and to examine the effects of restrainer stiffness and gap on the response of the hinge-restrainer system. Cable restrainers were used to connect the two blocks, the number and gap of which were varied during the experiments. The experimental results indicated that impacts between the adjacent frames produce acceleration levels significantly higher than what is typically assumed in design. In all the restrained system cases, restrainers were capable of reducing hinge relative displacements and preventing span unseating. However, restrainer yielding occurred under strong input motions, especially when the restrainer gap was set to zero.
Experimental Evaluation of Longitudinal Seismic Performance of Bridge Restrainers at In-Span Hinges
Author: AG. Vlassis
Publisher:
ISBN:
Category : Bridges
Languages : en
Pages : 10
Book Description
A specimen consisting of two box girder reinforced concrete blocks representing the adjacent spans of a reference bridge at an in-span hinge was constructed and tested under incrementally increasing input excitation to investigate the impact between adjacent bridge spans at in-span hinges, to evaluate the efficacy of restrainers in reducing relative displacements across the hinges, and to examine the effects of restrainer stiffness and gap on the response of the hinge-restrainer system. Cable restrainers were used to connect the two blocks, the number and gap of which were varied during the experiments. The experimental results indicated that impacts between the adjacent frames produce acceleration levels significantly higher than what is typically assumed in design. In all the restrained system cases, restrainers were capable of reducing hinge relative displacements and preventing span unseating. However, restrainer yielding occurred under strong input motions, especially when the restrainer gap was set to zero.
Publisher:
ISBN:
Category : Bridges
Languages : en
Pages : 10
Book Description
A specimen consisting of two box girder reinforced concrete blocks representing the adjacent spans of a reference bridge at an in-span hinge was constructed and tested under incrementally increasing input excitation to investigate the impact between adjacent bridge spans at in-span hinges, to evaluate the efficacy of restrainers in reducing relative displacements across the hinges, and to examine the effects of restrainer stiffness and gap on the response of the hinge-restrainer system. Cable restrainers were used to connect the two blocks, the number and gap of which were varied during the experiments. The experimental results indicated that impacts between the adjacent frames produce acceleration levels significantly higher than what is typically assumed in design. In all the restrained system cases, restrainers were capable of reducing hinge relative displacements and preventing span unseating. However, restrainer yielding occurred under strong input motions, especially when the restrainer gap was set to zero.
Experimental evaluation of seismic performance of bridge restrainers
Author: Anastasios G. Vlassis
Publisher:
ISBN:
Category : Bridge failures
Languages : en
Pages : 143
Book Description
Publisher:
ISBN:
Category : Bridge failures
Languages : en
Pages : 143
Book Description
Structural Assessment and Design of In-span Hinge Details in Reinforced Concrete Box-girder Bridges
Author: Matías Andrés Hube Ginestar
Publisher:
ISBN:
Category :
Languages : en
Pages : 754
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 754
Book Description
Experimental and Analytical Seismic Studies of a Four-span Bridge System with Innovative Materials
Author: Carlos Alonso Cruz-Noguez
Publisher:
ISBN:
Category :
Languages : en
Pages : 1524
Book Description
As part of a multi-university project utilizing the NSF Network for Earthquake Engineering Simulation (NEES), a quarter-scale model of a four-span bridge incorporating plastic hinges with different advanced materials was tested to failure on the three shake table system at the University of Nevada, Reno (UNR). The bridge was the second test model in a series of three 4-span bridges, with the first model being a conventional reinforced-concrete (RC) structure. The purpose of incorporating advanced materials was to improve the seismic performance of the bridge with respect to two damage indicators: (1) column damage and (2) permanent deformations. The goals of the study presented in this document were to (1) evaluate the seismic performance of a 4-span bridge system incorporating SMA/ECC and built-in rubber pad plastic hinges as well as post-tensioned piers, (2) quantify the relative merit of these advanced materials and details compared to each other and to conventional reinforced concrete plastic hinges, (3) determine the influence of abutment-superstructure interaction on the response, (4) examine the ability of available elaborate analytical modeling techniques to model the performance of advanced materials and details, and (5) conduct an extensive parametric study of different variations of the bridge model to study several important issues in bridge earthquake engineering. The bridge model included six columns, each pair of which utilized a different advanced detail at bottom plastic hinges: shape memory alloys (SMA), special engineered cementitious composites (ECC), elastomeric pads embedded into columns, and post-tensioning tendons. The design of the columns, location of the bents, and selection of the loading protocol were based on pre-test analyses conducted using computer program OpenSees. The bridge model was subjected to two-horizontal components of simulated earthquake records of the 1994 Northridge earthquake. Over 340 channels of data were collected. The test results showed the effectiveness of the advanced materials in reducing damage and permanent displacements. The damage was minimal in plastic hinges with SMA/ECC and those with built-in elastomeric pads. Conventional RC plastic hinges were severely damaged due to spalling of concrete and rupture of the longitudinal and transverse reinforcement. Extensive post-test analytical studies were conducted and it was determined that a computational model of the bridge that included bridge-abutment interaction using OpenSees was able to provide satisfactory estimations of key structural parameters such as superstructure displacements and base shears. The analytical model was also used to conduct parametric studies on single-column and bridge-system response under near-fault ground motions. The effects of vertical excitations and transverse shear-keys at the bridge abutments on the superstructure displacement and column drifts were also explored.
Publisher:
ISBN:
Category :
Languages : en
Pages : 1524
Book Description
As part of a multi-university project utilizing the NSF Network for Earthquake Engineering Simulation (NEES), a quarter-scale model of a four-span bridge incorporating plastic hinges with different advanced materials was tested to failure on the three shake table system at the University of Nevada, Reno (UNR). The bridge was the second test model in a series of three 4-span bridges, with the first model being a conventional reinforced-concrete (RC) structure. The purpose of incorporating advanced materials was to improve the seismic performance of the bridge with respect to two damage indicators: (1) column damage and (2) permanent deformations. The goals of the study presented in this document were to (1) evaluate the seismic performance of a 4-span bridge system incorporating SMA/ECC and built-in rubber pad plastic hinges as well as post-tensioned piers, (2) quantify the relative merit of these advanced materials and details compared to each other and to conventional reinforced concrete plastic hinges, (3) determine the influence of abutment-superstructure interaction on the response, (4) examine the ability of available elaborate analytical modeling techniques to model the performance of advanced materials and details, and (5) conduct an extensive parametric study of different variations of the bridge model to study several important issues in bridge earthquake engineering. The bridge model included six columns, each pair of which utilized a different advanced detail at bottom plastic hinges: shape memory alloys (SMA), special engineered cementitious composites (ECC), elastomeric pads embedded into columns, and post-tensioning tendons. The design of the columns, location of the bents, and selection of the loading protocol were based on pre-test analyses conducted using computer program OpenSees. The bridge model was subjected to two-horizontal components of simulated earthquake records of the 1994 Northridge earthquake. Over 340 channels of data were collected. The test results showed the effectiveness of the advanced materials in reducing damage and permanent displacements. The damage was minimal in plastic hinges with SMA/ECC and those with built-in elastomeric pads. Conventional RC plastic hinges were severely damaged due to spalling of concrete and rupture of the longitudinal and transverse reinforcement. Extensive post-test analytical studies were conducted and it was determined that a computational model of the bridge that included bridge-abutment interaction using OpenSees was able to provide satisfactory estimations of key structural parameters such as superstructure displacements and base shears. The analytical model was also used to conduct parametric studies on single-column and bridge-system response under near-fault ground motions. The effects of vertical excitations and transverse shear-keys at the bridge abutments on the superstructure displacement and column drifts were also explored.
Evaluation and Design of Seismic Restrainers for In-span Hinges
Author: Panayiotis Trochalakis
Publisher:
ISBN:
Category : Concrete bridges
Languages : en
Pages : 166
Book Description
Publisher:
ISBN:
Category : Concrete bridges
Languages : en
Pages : 166
Book Description
Experimental and Computational Evaluation of Current and Innovative In-span Hinge Details in Reinforced Concrete Box-girder Bridges
Author: Matias A. Hube
Publisher:
ISBN:
Category : Box girder bridges
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category : Box girder bridges
Languages : en
Pages :
Book Description
Experimental and Computational Evaluation of Reinforced Concrete Bridge Beam-column Connections for Seismic Performance
Author: Clay Joshua Naito
Publisher:
ISBN:
Category : Bridges, Concrete
Languages : en
Pages : 262
Book Description
Publisher:
ISBN:
Category : Bridges, Concrete
Languages : en
Pages : 262
Book Description
Experimental Evaluation of the Seismic Resistance of a Slab-on-girder Highway Bridge
Author: Behzad Mahmoodzadegan
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Seismic Engineering, Research and Practice
Author: Charles Alan Kircher
Publisher:
ISBN:
Category : Nature
Languages : en
Pages : 960
Book Description
Publisher:
ISBN:
Category : Nature
Languages : en
Pages : 960
Book Description
Experimental and Computational Evaluation of Current and Innovative In-span Hinge Details in Reinforced Concrete Box-girder Bridges
Author: Matias A. Hube
Publisher:
ISBN:
Category : Box girder bridges
Languages : en
Pages : 167
Book Description
Publisher:
ISBN:
Category : Box girder bridges
Languages : en
Pages : 167
Book Description