Seminar - Chadchart Sittipunt - Cyclic Behaviour of Reinforced Concrete Structural Walls with Diagonal Web Reinforcement

Wednesday, May 8, 2002, 1.10 - 1.40 pm
Civil Engineering Lecture Room 3

Abstract

A series of four reinforced concrete walls were tested to failure to evaluate the influence of diagonal web reinforcement on the hysteretic response. Two walls contained conventional horizontal and vertical web reinforcement and two walls contained inclined reinforcement. Reinforcement details were representative of construction practice in regions of low to moderate seismic risk. A single layer of web reinforcement was used and the transverse reinforcement in the boundary elements did not confine the concrete core.

Both walls with conventional web reinforcement failed due to web crushing. Pinched shapes characterized the hysteresis curves for top displacement and shear distortion near the base. In contrast, the walls with diagonal reinforcement displayed rounded hysteresis curves, and failed due to crushing of the boundary elements. The choice of web reinforcement did not have a significant influence on the maximum lateral load resisted by the walls, but measured crack widths were less, and more energy was dissipated by the walls with diagonal reinforcement during loading cycles to comparable levels of displacement. Analytical results from finite element analyses also indicated that web diagonal reinforcement was effective in transferring shear force to base of walls, especially during load reversals when most diagonal cracks in concrete remained open and compressive struts in concrete were not effective in transferring shear force.

Keywords: Cyclic lateral loading, Diagonal reinforcement, Hysteretic behavior, Reinforced concrete structural walls, Shear strength, Wall reinforcement


Brief CV:

Dr Chadchart Sittipunt is an Assistant Professor in Civil Engineering at the department of Civil Engineering, Chulalongkorn University, Bangkok Thailand. He received his BS from Chulalongkorn University in 1987, MS from MIT in 1989 and Ph.D. from the University of Illinois at Urbana-Champaign in 1993.

After receiving his Ph.D, Chadchart worked as a structural engineer at Skidmore, Owings and Merill in Chicago for two years. Then, he joined the Department of Civil Engineering, Chulalongkorn University in 1996. His research interests are in the areas of finite element analysis of RC structures, cyclic behavior of RC members, structural fire safety and durability of RC structures.

Dr.Sittipunt has been selected to receive the 2001-2002 Australia-Asia Fellowship. He will be working on a CSIRO/University of Sydney research program on service life modelling of concrete structures in aggressive sulfate conditions. This research aims at developing a mathematical model to predict the service life of concrete structural members exposed to aggressive sulfate conditions. The fellowship started in February 2002 for a period of one year.