Verification of Bridge Foundation Fixity for Three Different Types of Soil

Author

Syed Zeeshan, Southern Illinois University CarbondaleFollow

Date of Award

5-1-2016

Degree Name

Master of Science

Department

Civil Engineering

First Advisor

Hsiao, Jan

Abstract

The purpose of this study is to investigate the footing fixity effect on the lateral deflection of a bridge pier for different types of soil. Generally, the rotational restraint coefficient at top and bottom of pier (degree of fixity of the pier) is used to compute the effective length factor of pier which is in turn used to determine the pier deflection. The magnitude of the deflection is used to determine whether the p-delta force effect should be considered while designing the pier. However, the pier deflection is usually computed by assuming that the pier footing is completely fixed to the ground. In case of soil under footing, rotational restraint coefficient is taken as five for all types of soils. In this study, finite element analysis method was used to determine the pier deflection by providing three actual soil environments and compare the results with the traditional approach. Hence, the rotational restraint coefficient will be modified according to the deflection computed from the finite element analysis.