Cost‐optimal design of river dikes using probabilistic methods

Abstract

Given the large investments in dike construction and reinforcements, optimisation of these interventions could contribute to significant cost savings. In this study, a probabilistic method is developed for obtaining the geometry of a river dike cross‐section that fulfils a specified target reliability at a minimal cost. The method takes into account multiple relevant failure mechanisms and various geometric parameters of the dike. Large numbers of cross‐sections are generated and the reliability for each section is computed using FORM, Monte Carlo sampling, and numerical integration. The method is applied to several cases representing typical river dike profiles that are found in the Netherlands. Results show that for the optimal geometry the largest fraction of the target failure probability is assigned to those mechanisms with a relatively high cost of reinforcement. Also, comparison with the current semi‐probabilistic design guidelines shows that a decrease in costs of up to 15% could be reached with the new optimisation method.

Deep Uncertainty Surrounding Coastal Flood Risk Projections: A Case Study for New Orleans

“…Our analysis considers overtopping to account for 100% of the total probability of failure and serves to provide an upper bound on the system reliability ( Figure 4). We confirmed that our results are not significantly altered by prescribing overtopping to account for 60% or 80% of the total probability of failure, which is representative of the plausible range of failure modes (Bischiniotis et al, 2016) (see Figures S2 and S3). A more detailed probabilistic treatment of the different failure modes outlined here, as well as pumping system or floodgate failure, is beyond the scope of this study.…”

“…Optimal levee designs indicate that the relative contributions of overtopping versus piping or slope instability failures to the total levee failure probability vary depending on site-specific properties, but overtopping is the dominant failure mode (Johnson et al, 2013;Bischiniotis et al, 2016). Our analysis considers overtopping to account for 100% of the total probability of failure and serves to provide an upper bound on the system reliability ( Figure 4).…”

Re-evaluating safety risks of multifunctional dikes with a probabilistic risk framework

“…Macro stability is calculated within the program D-Geo Stability (Brinkman and Nuttall, 2018) with the stability method by Van (2001) and ground water model by TAW (2004). The method by Van (2001), like the Bishop (1955) method, calculates the sum of the driving moments (S) and the total resisting moment (R) along the slip plane. However, it also accounts for uplift forces on the interface of aquifers present beneath most dikes.…”

“…The stability of the slope is calculated with the method by Van (2001) for the slip plane and works on the same principle as the method by Bishop (1955). The main difference between the methods is the separation of the slip plane in an active circle connected by a straight section followed by a passive circle.…”

Assessment of Infrastructures Assets Induced by Water Level Fluctuation along the Bengawan Solo River

“…For instance, stability of embankment and infrastructure is often influenced by drying-wetting condition during water level fluctuation. Piping phenomenon, as one of the cause of river embankment failure, is induced by the water-level difference between the inner and the outer part of the river embankment, and failure happens when the resisting moment becomes lower than the driving moment (Bischiniotis et al, 2016). In detail, piping induced by the rapid draw down phenomenon and high water level during rainy season affects the worst piping effect.…”