HPP PROJECT DESCRIPTION
PROJECT NUMBER:
01221
PROJECT TITLE:
Feasibility Study on Dynamic Bridge Load Rating
PRINCIPAL INVESTIGATORS:
Dr. Shen-En Chen, P.E.
Department of Civil and Environmental Engineering,
The University of Alabama at Birmingham
Telephone: (205)-934-8433
Fax: (205)-934-9855
Dr. Norbert Delatte, P.E.
Department of Civil and Environmental Engineering
The University of Alabama at Birmingham
Telephone: (205) 934-8436
Fax: (205) 934-9855
Dr. B.J. Stephens, P.E.
Department of Mechanical Engineering
The University of Alabama at Birmingham
Telephone: (205) 934-8468
Fax: (205) 934-9855
PROJECT OBJECTIVE:
The main objective of this research is to conduct a feasibility study on using ambient vibration measurements to quantify bridge load capacity, as an evaluation measure for safety of bridges under load. Specific objectives include investigating the state of the art of dynamic testing of bridges and evaluating actual field ambient vibrations on selected bridges.
PROJECT ABSTRACT:
Full-scale load tests are sometimes used to determine the actual load capacity of bridges that have questionable or deficient load capacity. However, load tests, whether dynamic or static, require temporary shut down of the bridges and disrupt traffic. Additionally, they are not cost effective. This proposal will study whether field measurements of bridge vibration under regular traffic can be used to retrieve useful information to complement existing load tests and analyses to improve bridge load rating. The proposed works includes literature reviews, laboratory tests on bridge models and full-field vibration measurements on actual bridges. The intended outcome of this research is a testing methodology that can be used to accurately monitor bridge performance with minimum traffic interruption.
PROJECT TASK DESCRIPTIONS:
Task 1: Conduct a literature search on the
state-of-the-art in bridge dynamic testing.
Task 2:
Interview bridge vibration experts to learn from their collective experiences.
Task 3: Collaborate with State bridge engineers to
determine appropriate bridges for vibration measurements and testing.
Task 4: Conduct laboratory studies on a bridge model
to establish testing procedures and a signal-processing algorithm.
Task 5: Concurrent with ALDOT bridge testing, conduct
vibration measurements.
Task 6: Conduct ambient vibration measurements during normal traffic flow.
Task 7: Propose a load capacity determination algorithm and testing methodology.
Task 8: Write a final report.
MILESTONES AND DATES:
Project start, Jan 2001
Tasks 1-2, Jan - May 30
Tasks 3-4, Apr 1 - Jun 30
Tasks 5-6, Oct 30
Tasks 7-8, Nov 1 – Dec 25
Submit final report Dec 25 2001
BUDGET:
One-year project; UTCA $53,132; total budget $106,256.
STUDENT INVOLVEMENT:
One Master’s level graduate student and one undergraduate student will be hired to work on this project. This research will become the graduate student’s Master’s thesis. This project will provide a research opportunity to the undergraduate student. To promote diversity, a minority student will be given priority to both positions.
RELATIONSHIP TO OTHER RESEARCH PROJECTS:
The proposed research closely tied to other UTCA projects that may involve in Bridge Management System (BMS) and bridge safety issues.
TECHNOLOGY TRANSFER ACTIVITIES:
The
success of this course may further extended to include other transportation
systems and applications. Potential
journal and technical note publications will be pursued. The results of this research will be
presented at the International Modal Analysis Conference or equivalent
conferences. A Master’s thesis will be
accomplished from this research.
POTENTIAL BENEFITS OF THE PROJECT:
The
long-term benefits of this project will be to improve safety and management of
the infrastructure of Alabama. However,
the results of vibration measurements on the selected bridges can directly
benefit state DOT maintenance engineers by validating their strain measurements
during their bridge load tests.
Other
long-term benefits of this project include making the transportation research
in the areas of structural rehabilitation and inspection more competitive in
the national level. The modal testing
technology developed can also be extended to protective designs and studies of
bridges, such as tornado or strong wind effects, etc.
TRB KEYWORDS:
Bridge safety, BMS, Bridge Management Systems, load rating, load tests, bridge rating.