Innovative techniques for seismic-resistant bridge columns under ground motion excitations

“This dissertation provides innovative alternative solutions for replacing conventional reinforced concrete columns. The proposed columns displayed enhanced seismic resistance and properties compared to their counterpart conventional columns. Two main techniques were followed and proposed to develop seismic-resistant columns. The first technique utilized rubberized concrete to internally enhance energy dissipation and damping. Materials testing of rubberized concrete with scrap tire replacement of fine aggregates were performed to evaluate its dynamic properties. Shaking table testing of a rubberized concrete column was performed and the behavior was compared to that of the conventional one. The rubberized column showed an increase of 16% in energy dissipation compared to the conventional column. This solution also had the benefit of using recycled tire rubber, which produced green concrete. The second technique utilized post-tensioned segmental columns with double-skin cross section and external energy dissipaters. Three columns with different configurations were tested on the shaking table and compared with the conventional column. These columns outperformed the conventional column; especially regarding the residual drift. The peak drift for the posttensioned columns was 8.85% with a residual drift of 0.08% compared to 4.8% peak drift with 1.5% residual drift for the conventional column. Three-dimensional finite element models for the post-tensioned columns were developed using LS-DYNA software. The effects of ground motion characteristics including far-field motions, near-fault motions without forward-directivity, near-fault motions with forward-directivity, and near-fault motions with fling-step on full-scale column models were investigated. An analytical model for the design of post-tensioned columns was provided”--Abstract, page iv.

Name thesis:degree_name

Ph. D. in Civil Engineering

Grantor

Missouri University of Science and Technology

Author dc:creator

• Moustafa, Ayman A.

• Bridge Columns
• Finite Element
• Rubberized Concrete
• Segmental Columns
• Seismic Resistant
• Shaking Table
• Civil Engineering

Repository record dc:identifier

https://scholarsmine.mst.edu/doctoral_dissertations/3106

OAI identifier oai:identifier

oai:scholarsmine.mst.edu:doctoral_dissertations-4111