Open Collections

Seismic strengthening and retrofit of damaged and deficient circular reinforced concrete bridge piers with ferrocement

University of British Columbia

In Canada and abroad, a significant number of bridges that enable the operation of the transportation industry are in poor condition and require immediate attention. Many bridges are also approaching or have surpassed their anticipated design service life. As a result, deficient construction due to their age coupled with deterioration puts them at risk of collapsing. Moreover, many bridges around the world are located in high-risk seismic zones and were built before the implementation of seismic provisions, and therefore lack proper seismic detailing. Thus, there is a need to study and introduce an effective, readily available, and inexpensive method of bridge rehabilitation so that bridge components can be strengthened to avoid catastrophic failure. Ferrocement, which is a composite structural material made of cementitious mortar and steel wire mesh, has seen its emergence as a viable strengthening material. This thesis expands the knowledge and research field surrounding the seismic response of ferrocement-jacketed reinforced concrete (RC) bridge piers. In this study, preliminary experiments were first carried out by conducting mechanical tests on ferrocement materials to evaluate the performance of various material combinations. Then, the confinement effect of ferrocement was investigated using two 1/3-scale RC bridge piers, each strengthened with a ferrocement jacket made from three layers of 19-gauge mesh and Portland cement mortar. The first bridge pier – a seismically damaged conventional pier, and the second – an undamaged shear-deficient pier, were subjected to an axial load and a cyclic lateral load. The piers’ seismic responses were evaluated by analyzing their hysteretic behaviour during loading and comparing the findings to past researchers’ tests. Results showed that using ferrocement to strengthen a seismically damaged bridge pier can restore its flexural capacity, energy dissipation capacity, and ductility. When using ferrocement to strengthen a seismically deficient pier, results showed that the ductility and energy dissipation capacity can be enhanced, and the flexural and moment capacities can be increased, preventing total collapse. The findings of this research prove that ferrocement jacketing can effectively rehabilitate damaged and deficient bridge piers in earthquake scenarios. This research could assist with code implementation, and encourage efficient and inexpensive up-gradation of transportation infrastructure.

Text

2020-06-01

Attribution-NonCommercial-NoDerivatives 4.0 International

http://hdl.handle.net/2429/74626

Civil Engineering

University of British Columbia

UBCO

http://creativecommons.org/licenses/by-nc-nd/4.0/