Author: Peter DusickaPublisher:
ISBN:
Category :
Languages : en
Pages : 11
Book Description
Research Project Work Plan for Seismic Performance Design Criteria for Existing Bridge Bent Plastic Hinge Regions
Author: Peter DusickaSeismic Performance Design Criteria for Bridge Bent Plastic Hinge Regions
Author: A. K. M. Golam MurtuzPublisher:
ISBN:
Category : Concrete bridges
Languages : en
Pages : 109
Book Description
The main objective of this research was to quantify the material strain limits for seismic assessment of existing sub-standard reinforced concrete bridge bents considering operational performance design criteria. Limited confidence exists in the current material strain limit state for operational performance criteria due to lack of experimental results considering the typical detailing of Oregon bridges and the cumulative damage effect resulting from an anticipated long-duration Cascadia Subduction Zone (CSZ) event. Component details for bridge bents such as geometry and reinforcing details were determined through a statistical analysis of available bridge drawings built prior to 1990 in the State of Oregon. Three full-scale bridge bent column-footing subassembly specimens were constructed and subjected to reverse cyclic lateral deformations utilizing a traditional loading protocol and a protocol representing the demands expected from a CSZ earthquake. The tests were designed so that variable axial loading could be applied in order to simulate the secondary effects experienced in a column that is part of a multi-column bent during an earthquake event. Material strains along with global and local deformation quantities were measured with a suite of external and internal sensors mounted to and embedded in the specimens. Despite having sub-standard seismic detailing, all three specimens exhibited ductile behavior under reverse cyclic lateral loading, achieving a minimum displacement ductility of 8.0. The obtained results also suggest that the material strain limits currently used for the seismic evaluation of existing bridges in Oregon considering operational performance criteria are conservative, but may still require further experimental validation. Finally, strain limits based on previous research at Portland State University (PSU) were compiled and combined with the results from this study to propose recommended strain limit values.
Seismic Performance Design Criteria of Existing Bridge Bent Plastic Hinge Region and Rapid Repair Measures of Earthquake Damaged Bridges Considering Future Resilience
Author: Publisher:
ISBN:
Category : Bridges
Languages : en
Pages : 0
Book Description
The main objective of this research was to evaluate the seismic performance of existing sub-standard reinforced concrete (RC) bridge column-spread footing subassemblies and to quantify the material strain limits through a full-scale experimental program. A total of six column-footing test specimens with pre-1990 construction details were subjected to reverse cyclic lateral loading, utilizing a conventional three-cycle symmetric loading protocol and a protocol representing the demands expected from a CSZ earthquake. Additionally, the tests were designed so that variable axial loading could be applied to simulate the secondary load effects experienced during an earthquake in a column that is part of a multi-column bent. A rapid repair method incorporating semi-permanent installation was also developed, anticipating the need for quick measures following the Cascadia Subduction Zone (CSZ) earthquake, which is expected to damage the existing bridges in the Pacific Northwest and spread geographically throughout the region. The proposed repair methodology uses capacity design principles to protect the remainder of the bridge from future earthquakes and eradicates the need for establishing rebar continuity, resulting in a less labor-intensive repair method. The adopted concept is to utilize U-shaped metallic plates as externally attached ductile fuses to be anchored to the non-damaged part of the column, hence bypassing the damaged zone to restore the lateral capacity.
Comprehensive Specification for the Seismic Design of Bridges
Author: National Cooperative Highway Research ProgramPublisher: Transportation Research Board
ISBN: 0309067537
Category : Bridges
Languages : en
Pages : 55
Book Description
Seismic Performance and Failure Behavior of Plastic Hinge Regions in Flexural Bridge Columns
Author: Yael D. HoseDevelopment of a Precast Bent Cap System for Seismic Regions
Author: José Ignacio RestrepoPublisher: Transportation Research Board National Research
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 124
Book Description
The report explores the development and validation of precast concrete bent cap systems for use throughout the nation's seismic regions. The report also includes a series of recommended updates to the American Association of State Highway and Transportation Officials (AASHTO) Load and Resistance Factor Design (LRFD) Bridge Design Specifications, Guide Specification for LRFD Seismic Bridge Design, and AASHTO LRFD Bridge Construction Specifications that will provide safe and reliable seismic resistance in a cost-effective, durable, and constructible manner. A number of deliverables are provided as attachments to NCHRP Report 681, including design flow charts, design examples, example connection details, specimen drawings, specimen test reports, and an implementation plan from the research agency's final report. These attachments are only available online at http://www.trb.org/Publications/Blurbs/Development_of_a_Precast_Bent_Cap_System_for_Seism_164866.aspx.TRB's National Cooperative Highway Research Program (NCHRP) Report 681: Development of a Precast Bent Cap System for Seismic Regions explores the development and validation of precast concrete bent cap systems for use throughout the nation's seismic regions. The report also includes a series of recommended updates to the American Association of State Highway and Transportation Officials (AASHTO) Load and Resistance Factor Design (LRFD) Bridge Design Specifications, Guide Specification for LRFD Seismic Bridge Design, and AASHTO LRFD Bridge Construction Specifications that will provide safe and reliable seismic resistance in a cost-effective, durable, and constructible manner. A number of deliverables are provided as attachments to NCHRP Report 681, including design flow charts, design examples, example connection details, specimen drawings, specimen test reports, and an implementation plan from the research agency's final report. These attachments, which are only available online.
Seismic Performance and Retrofit of Multi-column Bridge Bents
Author: David I. McLeanPublisher:
ISBN:
Category : Bridges
Languages : en
Pages : 68
Book Description
Design Guidelines for Assessment Retrofit and Repair of Bridges for Seismic Performance
Author: M. J. N PriestleyPublisher:
ISBN:
Category : Bridges
Languages : en
Pages : 350
Book Description
Guide Specifications for Seismic Isolation Design
Author: Publisher: AASHTO
ISBN: 1560514566
Category : Technology & Engineering
Languages : en
Pages : 63
Book Description
This edition is based on the work of NCHRP project 20-7, task 262 and updates the 2nd (1999) edition -- P. ix.
AASHTO Guide Specifications for LRFD Seismic Bridge Design
Author: Publisher: AASHTO
ISBN: 156051521X
Category : Bridges
Languages : en
Pages : 271
Book Description
This work offers guidance on bridge design for extreme events induced by human beings. This document provides the designer with information on the response of concrete bridge columns subjected to blast loads as well as blast-resistant design and detailing guidelines and analytical models of blast load distribution. The content of this guideline should be considered in situations where resisting blast loads is deemed warranted by the owner or designer.