TY - JOUR
T1 - Time-dependent clear-water scour for submerged bridge flows
AU - Guo, Junke
N1 - Funding Information:
This research was supported by the US FHWA Hydraulics R&D Programme, Contract Nos DTFH-04-C-00037 and DTFH61-11-D-00010. The author thanks Mr Oscar Berrios and Dr Lianjun Zhao for collecting the laboratory data.
PY - 2011/12/1
Y1 - 2011/12/1
N2 - The current design of bridge foundations based on equilibrium scour depths is much larger than the real maximum scour depth since peak flood periods are often too short to reach equilibrium conditions. Based on a tested hypothesis on the time rate of scour, this research presents a power-exponential equation for the time-dependent clear-water scour depth including a nonzero initial condition for submerged bridge flows. For zero initial conditions, the proposed equation is reduced to a log or power law during the initial phase and an exponential decay near the equilibrium condition. The proposed equation reduces design depths according to design flows and their peak periods, translating into significant savings in the construction of bridge foundations. With a real-time monitoring system, the proposed equation also predicts time-series scour depths during floods, helping bridge managers formulate timely corrective strategies.
AB - The current design of bridge foundations based on equilibrium scour depths is much larger than the real maximum scour depth since peak flood periods are often too short to reach equilibrium conditions. Based on a tested hypothesis on the time rate of scour, this research presents a power-exponential equation for the time-dependent clear-water scour depth including a nonzero initial condition for submerged bridge flows. For zero initial conditions, the proposed equation is reduced to a log or power law during the initial phase and an exponential decay near the equilibrium condition. The proposed equation reduces design depths according to design flows and their peak periods, translating into significant savings in the construction of bridge foundations. With a real-time monitoring system, the proposed equation also predicts time-series scour depths during floods, helping bridge managers formulate timely corrective strategies.
KW - Bridge scour
KW - clear-water scour
KW - pressure flow
KW - real-time monitoring
KW - submerged flow
KW - time-dependent scour
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U2 - 10.1080/00221686.2011.616364
DO - 10.1080/00221686.2011.616364
M3 - Article
AN - SCOPUS:84857304828
SN - 0022-1686
VL - 49
SP - 744
EP - 749
JO - Journal of Hydraulic Research
JF - Journal of Hydraulic Research
IS - 6
ER -