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A Comparative Study on Scour Depth Analysis Around Bridge Piers on Different Soils
Published in P. C. Thomas, Vishal John Mathai, Geevarghese Titus, Emerging Technologies for Sustainability, 2020
Ahiya Elizebeth Joy, Arya Shaji, K. V. Ashish, P. S. Muhammed Aslam, Sunith John David
Scour is the erosive action of water carrying away sediments from river bed and riverbanks, and around piers and abutments of a bridge. This phenomenon is considered as the major cause of bridge failures. The amount of reduction in the streambed level below the bed level of the river prior to the commencement of scour is referred as the scour depth. A scour hole is defined as depression left behind when sediment is washed away from the riverbed near the bridge piers. The formation of scour holes around bridge piers in natural rivers is a common phenomenon. Bridge scour is recognized as a major threat to the safety of bridge structures. Excessive scouring around the bridge piers can be detrimental leading towards early failure of a bridge structure. Scouring around bridge piers is a major cause of failure, and a major contributor in excessive construction and maintenance costs.
The effect of local scour of a single pier on the vibration parameters of a multi-span bridge under seismic excitation
Published in Nigel Powers, Dan M. Frangopol, Riadh Al-Mahaidi, Colin Caprani, Maintenance, Safety, Risk, Management and Life-Cycle Performance of Bridges, 2018
A. Anžlin, L.J. Prendergast, K. Gavin, M.P. Limongelli
Bridge scour is the term used to describe the removal of soil from around bridge foundations caused by adverse hydraulic action (Hamill 1999). There are three main forms of scour: general, contraction and local scour. General scour occurs naturally in river channels and is a fundamental behavior of evolving rivers. It involves the natural erosion and deposition behavior of a river channel that occurs due to changes in the hydraulic parameters governing channel form, for example flow rate or sediment supply (Forde et al. 1999; Federico et al. 2003). Contraction scour occurs due to the sudden increase in flow velocity at the location of a bridge caused by a narrowing of the river channel, as water is channeled between the sub-structural elements of a bridge (piers or abutments). The increased velocity has an associated increase in the shear stresses imposed on the streambed sediment. Once the threshold shear stress of a given bed material is surpassed, sediments are mobilized (Briaud et al. 1999). Finally, local scour occurs around individual piers or abutments due to their disruption of the local water-flow characteristics. The flow is channeled downward once it meets the obstruction, which can cause scour holes to develop on the upstream end of a pier due to the generation of horseshoe vortices. Furthermore, the flow separating at the sides of the pier causes wake vortices to form which can expand the scour hole around the pier (Heidarpour et al. 2010). Figure 1 shows a schematic of the scour process around a cylindrical pier-type object.
Framework for determining the dominant hazard of bridges under flood and seismic hazards
Published in Joan-Ramon Casas, Dan M. Frangopol, Jose Turmo, Bridge Safety, Maintenance, Management, Life-Cycle, Resilience and Sustainability, 2022
P.S. Firdaus, M. Akiyama, H. Matsuzaki, D.M. Frangopol, H. Ishibashi
Scour develops around bridge piers as a result of the erosive flow of water, and the corresponding excavation of bed material degrades the structural integrity of the bridge foundation. Several studies on bridge scour risk were reported by Zhu & Frangopol (2016), Liu et al. (2018, 2020), and Yang & Frangopol (2020), among others. Arneson et al. (2012) divided bridge scour into long-term aggradation and degradation, contraction scour, and pier/abutment scour. This study focuses only on the local scour of bridge piers. Nonetheless, the proposed estimation procedure can be expanded to other types of scour.
Comparison of risk-based methods for bridge scour management
Published in Sustainable and Resilient Infrastructure, 2023
M. Pregnolato, Pier Francesco Giordano, L.J. Prendergast, P.J. Vardanega, Maria Pina Limongelli
Bridge scour is defined as the erosion of soil from around bridge foundations and abutments, which in turn can lead to a reduction in support capacity (e.g., Ettema et al., 2017; Hager, 2007; Maddison, 2012; Melville & Coleman, 2000; Whitbread et al., 1996; Whitbread et al., 2000); it is a process that may be exacerbated by high river and/or turbulent flows (e.g., due to flooding). The phenomenon of scour includes different types, namely general, contraction/constriction and local scour (Maddison, 2012; Melville & Coleman, 2000). A range of damage mechanisms and failure modes are triggered when scour holes reveal the bottom of or undermine shallow foundations, compromising the integrity and safety of the entire structure (Bento et al., 2018; Bento, Couto, et al., 2022; Mondoro & Frangopol, 2018; Wang et al., 2014). To maintain bridge resilience, owners and operators should consider how best to prevent, detect, and mitigate scour effects (Tubaldi et al., 2022).
Wavelet-based operating deflection shapes for locating scour-related stiffness losses in multi-span bridges
Published in Structure and Infrastructure Engineering, 2023
Eugene J. OBrien, Daniel P. McCrum, Muhammad Arslan Khan, Luke J. Prendergast
Bridge scour is the term used to describe the washing away of soil (erosion) near bridge foundations due to hydraulic action (Hamill, 1999). Scour is responsible for a majority of bridge failures worldwide (Maddison, 2012; Melville & Coleman, 2000; Wardhana & Hadipriono, 2003) and can cause significant economic losses and travel disruptions (Lagasse et al., 1995). Scour reduces the elevation of the soil surface profile in the vicinity of bridge foundations, which affects the capacity and stiffness of these systems (Malekjafarian et al., 2020). The detection of scour and scour-related damage in structures is a problem that has received increasing research attention in recent years (Bao et al., 2017; Bao & Liu, 2017; Fitzgerald et al., 2019a, 2019b; Foti & Sabia, 2011; Giordano et al., 2020; Ju, 2013; Kong & Cai, 2016; Li et al., 2020; Malekjafarian et al., 2020; Prendergast et al., 2016a, 2016b, 2017; Xiong et al., 2018).
Investigation on scour process around bridge foundations considering soil particles and layer distributions
Published in European Journal of Environmental and Civil Engineering, 2022
Chen Wang, Fayun Liang, Xiong (Bill) Yu
Scour around bridge foundation, i.e. bridge scour, is a complex phenomenon due to localised flow field around bridge structure resulting from the interactions between stream, structure, and sediments, and has been identified to be one of the most common causes of bridge failures in the United States (Arneson et al., 2012; Cook et al., 2015; Shirhole & Holt, 1991). It is a dynamic process affected by many factors, such as long-term general degradation of the riverbed, environmental changes, and seasonal climatic effects. The development of scour holes has a significant influence on the mechanical behaviour of piles, particularly their resistance to lateral loads (Lin et al., 2014a, 2016; Shwiyhat & Xiao, 2010; Tu et al., 2015; Zhang et al., 2019). Since the initial research on scour in 1873, there have been numerous studies on this topic through experimental and numerical simulation (Li et al., 2017; Lin et al., 2014b; Li & Tao, 2016; Melville & Sutherland, 1988).