Many structures in earthquake prone areas are constructed using reinforced concrete. In seismically resistant design, proper behavior of the reinforced concrete structural elements depends a great deal on the ductility of the structure. Confinement of concrete in critical locations plays a significant part in achieving ductile behavior of structures. In this research, basic mechanisms of confinement by rectilinear ties will be investigated using analytical models and experiments with laboratory specimens. A rational method will be developed to determine the required amount and configuration of confining steel which will result in economical and safe design of structures. Results from this research are expected to provide the basis for modifications and recommendation in the confinement provisions of various U.S. design codes such as American Concrete Institute ACI 318 and SEAOC. The Principal Investigator is highly qualified to conduct the research and the institution provides excellent support facilities. An award is recommended for the first year of this two-year complete project.
