Should Engineers be Concerned about Vulnerability of Highway Bridges to Potentially-Induced Seismic Hazards?

TL;DR

This paper assesses the seismic vulnerability of highway bridges in regions affected by human-induced earthquakes, focusing on fragility analysis of steel girder bridges considering regional uncertainties.

Contribution

It develops specific fragility curves for steel girder bridges accounting for regional uncertainties in ground motion, soil, and design practices, addressing a gap in seismic risk assessment for induced earthquakes.

Findings

Fragility curves indicate increased vulnerability in affected regions.

Uncertainty in ground motion and soil conditions significantly impacts seismic risk.

Results support infrastructure resilience planning in seismic zones.

Abstract

This paper evaluates the vulnerability of highway bridges in areas subjected to human induced seismic hazards that are commonly associated with petroleum activities and wastewater disposal. Recently, there has been a significant growth in the rate of such earthquakes, especially in areas of Texas, Oklahoma, and Kansas. The magnitudes of these earthquakes are usually lower than tectonic earthquakes that can occur in high seismic regions; however, such induced earthquakes can occur in areas that historically have had negligible seismicity. Thus, the infrastructure in these locations was likely designed for no to low seismic demands, making them vulnerable to seismic damage. Ongoing research is aimed at evaluating the vulnerability bridge infrastructure to these human induced seismic hazards. In this paper, fragility curves are developed specifically for steel girder bridges by considering major sources of uncertainty, including uncertainty in ground motions and local soil conditions expected in the Texas, Oklahoma, and Kansas region, as well as uncertainty in design and detailing practices in the area. The results of this fragility analysis are presented herein as a basis for discussion of potential seismic risks in areas affected by induced earthquakes.