Sri Sritharan Department of Civil, Construction & Evnironmental Engineering
T. A. Wilson Engineering Professor (515)294-5238 | sri@iastate.edu


Sponsors:

SGER: Soil-Structure Interaction of Bridge Columns in Frozen Environments


Sponsor(s): National Science Foundation(NSF)
Investigators: Sivalingam Sritharan(Principal Investigator)
David White (Co-Principal Investigator)
Muhannad Suleiman(Co-Principal Investigator)
Start Date: 08/01/2005
End Date: 10/31/2006
Keywords: Large Scale Testing of Structures, Soil Foundation & Structure Interaction(SFSI)


Research Objective:

This project explores temperature effects on soil-foundation-structure systems by studying bridge columns supported on cast-in-drilled-hole (CIDH) pile shafts. Through a large-scale outdoor experimentation, lateral load responses of three bridge columns in warm and frozen ground conditions will be studied to understand the seasonal temperature effects on soil-structure interaction as well as system ductility. A preliminary analytical investigation revealed that freezing conditions at a ground temperature near -20°C may reduce structure displacement capacity by 70% and increase column shear demand by 35%, due to relocation and reduction in spread of plasticity in the pile shaft. An analytical study utilizing the measured material properties and in-situ soil test data will be performed to characterize the responses of the three bridge column systems. Comparing the analytical and experimental results, seismic design implications of the effects of seasonal freezing on soil-foundation-structure systems will be presented. In addition, a plan for detailed investigation on this subject area will be developed.