Rating and reliability of existing bridges in a network

Currently, the load rating is the method used by State DOTs for evaluating the safety and serviceability of existing bridges in the United States. In general, load rating of a bridge is evaluated when a maintenance, improvement work, change in strength of members, or addition of dead load alters the condition or capacity of the structure. The AASHTO LRFD specifications provide code provisions for prescribing an acceptable and uniform safety level for the design of bridge components. Once a bridge is designed and placed in service, the AASHTO Manual for Condition Evaluation of Bridges provides provisions for determination of the safety and serviceability of existing bridge components. Rating for the bridge system is taken as the minimum of the component ratings. If viewed from a broad perspective, methods used in the state-of-the-practice condition evaluation of bridges at discrete time intervals and in the state-of-the-art probability-based life prediction share common goals and principles. This paper briefly describes a study conducted on the rating and system reliability-based lifetime evaluation of a number of existing bridges within a bridge network, including prestressed concrete, reinforced concrete, steel rolled beam, and steel plate girder bridges. The approach is explained using a representative prestressed concrete girder bridge. Emphasis is placed on the interaction between rating and reliability results in order to relate the developed approach to current practice in bridge rating and evaluation. The results presented provide a sound basis for further improvement of bridge management systems based on system performance requirements.
Journal Of Bridge Engineering


Experimental Determination of Resistance Characteristics of Support Details Used in Prestressed Concrete Bridge Girders
Baran, Eray; French, Catherine; Schultz, Arturo (American Society of Civil Engineers (ASCE), 2009-09-01)
Static load tests were performed on support details used at the ends of prestressed concrete pedestrian bridge girders to determine the resistance characteristics of girder supports in the direction perpendicular to the longitudinal axis of the girders. The specimens tested represent support details that have also been widely used in prestressed concrete highway bridges in Minnesota and in other states. Two specimens, one representing the free-end detail and one representing the restrained-end detail were s...
Efficiency of Seismic Isolation for Seismic Retrofitting of Heavy Substructured Bridges
Dicleli, Murat; Constantinou, Michael C. (American Society of Civil Engineers (ASCE), 2005-07-01)
In this paper, the efficiency of seismic isolation for seismic retrofitting of bridges with light superstructures and heavy substructures in the state of Illinois is studied. For this purpose, a representative bridge was selected by Illinois Department of Transportation. A detailed structural model of the bridge capable of simulating the nonlinear behavior of its components and soil-bridge interaction effects was first constructed. Iterative multimode response spectrum analysis (IMMRSA) of the bridge were c...
Comparative Study on the Effect of Number of Girders on Live Load Distribution in Integral Abutment and Simply Supported Bridge Girders
Yalcin, O. Fatih; Dicleli, Murat (SAGE Publications, 2013-06-01)
In this study, the effect of the number of prestressed concrete girders on the distribution of live load effects among the girders of integral abutment bridges (IABs) and simply supported bridges (SSBs) is investigated. For this purpose, two and three dimensional finite element models (FEMs) of several single-span IABs and SSBs are built and analyzed. In the analyses, bridges with various superstructure properties, such as span length, girder type and size, slab thickness are considered. The finite element ...
Improved Seismic Response of Multisimple-Span Skewed Bridges Retrofitted with Link Slabs
Sevgili, Gizem; Caner, Alp (American Society of Civil Engineers (ASCE), 2009-11-01)
Results of a recent bridge inventory evaluation indicated that about 50% of Turkish highway bridges have more than 30 degrees of skew angle and can be classified as irregular bridges. During the recent major earthquake in Turkey, multisimple-span bridges with continuous decks and link slabs performed well even though these bridges were in the vicinity of the fault line. This study aims to evaluate the improvements in seismic response of skew bridges in terms of forces and displacements when link slabs are a...
Evaluation of Top Flange Bracing Systems for Curved Box Girders
Topkaya, Cem; Williamson, Eric B. (American Society of Civil Engineers (ASCE), 2005-11-01)
In recent years, steel trapezoidal box girders for curved highway interchanges have become popular. For these bridge systems, significant steel girder cross-sectional stresses occur during the concrete casting sequence. To help resist construction loads, a lateral truss system is installed at a level close to the top flanges to form a "pseudo-closed" section, which has a higher torsional stiffness than an open U-section. Several recent incidents, ranging from the buckling of individual bracing members to th...
Citation Formats
F. Akgül, “Rating and reliability of existing bridges in a network,” Journal Of Bridge Engineering, pp. 383–392, 2003, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/35773.