Currently used specifications for the design and construction of concrete bridges are prescriptive specifications that define the required parameters and their minimum acceptance levels for a specific structural system. This methodology is based on certain assumptions and is designed to produce structures for a certain service life. For example, adhering to the AASHTO LRFD specifications in the design will produce a concrete bridge with minimum 75-year service life expectancy. This concrete bridge will meet certain (may be undefined) maintenance and life cycle cost criteria.
On the other hand, Performance Based Specification (PBS) will determine the required design criteria’s parameters such service life, durability, life cycle costs etc. and the minimum acceptance levels for these parameters. PBS allows alternate methodologies for meeting the acceptance levels. When using PBS, the prescriptive specifications will become the methodology for achieving these acceptance levels.
Performance Based Specifications will serve alternative contracting methods such as design-build very well by allowing innovative designs and materials to produce the desired outcomes of longer service life, more durable bridges at lower life cycle costs. PBS will also allow regional and local design and construction variations that will produce the most economical design that meets the performance requirements.
The purpose of this research is to establish a matrix of the following:
1- Design criteria parameters
2- Performance levels for each parameter
3- Methodologies for meeting these performance levels
4- Recommend roadmap and framework required for the development of complete Performance Based Specifications.
This research statement meets the strategic plan of the AASHTO T-10 Technical Committee on Concrete.