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ZusammenfassungDie horizontale Schichtung von Sedimentkörpern bewirkt, dass die effektive hydraulische Durchlässigkeit eines sedimentären Grundwasserleiters in horizontaler Richtung größer ist als in der vertikalen, was sich unter anderem auf die Ausbreitung des Absenktrichters bei Grundwasserentnahmen auswirkt. Um die großräumige hydraulische Anisotropie zu bestimmen, führten Maier et al. (2022a) an einem Testfeld am Oberrhein tiefenorientierte Pumpversuche mit einem Förderbrunnen mit drei Filterstrecken durch. Die Grundwasserentnahmen erfolgten nacheinander jeweils aus einer Tiefe. Die Absenkungen aller Versuche wurden in verschiedenen Abständen zum Förderbrunnen und verschiedenen Tiefen gemessen und gemeinsam mit einem Computermodell ausgewertet. In der vorliegenden Arbeit zeigen wir, dass die Interpretation von Absenkkurven bei Entnahme aus nur einer Tiefe zu Durchlässigkeitsbeiwerten führt, die vornehmlich die Bedingungen in der Entnahmetiefe widerspiegeln. Für die Bestimmung vertikaler Unterschiede der hydraulischen Durchlässigkeit und der hydraulischen Anisotropie ist es notwendig, Versuche mit mehreren Entnahmetiefen zu kombinieren. Der Arbeitsaufwand im Feld kann jedoch durch eine optimierte Beobachtungsstrategie reduziert werden.

The hydrological cycle is a complex system, composed of multiple variables, which in most cases are not measured. This is one of the reasons why it is a challenge to have models that adequately represent the expected discharges. The PUB initiative reinforces the need on having models that capture the different catchment interactions and represent various catchment processes. These models are more robust and thus can be more reliable to transfer to the ungauged catchments. In recent years, the field of hydrological research has focused on understanding and explaining the different processes present in catchments. Nevertheless, few applications that include pre- cipitation, the main responsible of runoff change,are found.Further understanding of the temporal and spatial dependence of the meteorological event triggering the floods is needed. In this study, an analysis of the meteorological event triggering the floods was carried out. The concept of entropy was used to characterize the temporal distribution of precipitation. It was found that the precipitation temporal entropy is a better indicator of hydrograph shape than the duration or the intensity. Further, the geographical interdependence of the amount of precipitation and the temporal precipitation entropy causing the floods was described looking at the association of sta- tions triples. This suggested that, up until a given quantile, flood events are more likely caused by precipitation events of total coverage. However, for larger quantile values, it is observed that as the quantile increases the probability of observing joint occurrence in space decreases. The tem- poral distribution of precipitation events causing the floods showed to be more associated in space than the amount of precipitation triggering the floods. Nonetheless, this temporal distribu- tion is not constant over all flood events, what can be attributed to d ifferent flood mechanisms. The Antecedent Precipitation Index (API) was used to explain the soil moisture content. The em- pirical distribution of (API) at the time of a flood was compared with empirical distributions of unconditioned (API) data series. T o this end, the Wilcoxon statistic and the Kolmogorov -Smirnov distance were used to compare the empirical distributions. The re sults showed that the soil mois- ture triggering the floods is not an annual extreme, rather a value close to the monthly maximum (API). Further, it was observed that the longer memory of the catchment gives more information about the occurrence of the flood. Additionally, in order to estimate the catchment reaction at the time of a flood, a regiona lization of the flood wave hydrographs was carried out. T o this end, three methods of defining the simi- larity of the floods were considered. In all three methods, the similarity matrices were generated using the random forest algorithm. The novelty of this procedure was the use of a supervised random forest to describe the similarity of the floods events. It was supervised given that the algorithm was trained to estimate a target variable. The proximity matrix was obtained by calcu- lating the joint occurrence of floods in the random forest space. For evaluating the estimation the hydrograph peak and the time to peak were used. In all three methods, the same tendencies were observed, an overestimation of the peak and an underestimation of the time to peak. However, the bias was observed to be smaller when an ensemble of similarity matrices was used as com- pared to having a single similarity matrix. Moreover, an approach using an unsupervised random forest was compared to the supervised one. It was found that the unsupervised random forest yields larger estimation errors. Finally, to estimate the volume of the flood event a rainfall-runoff model was modified to represent the study region. The model chosen in this study was EPIC. The model was calibrated to be more representative of the study region. To this end, the estimation errors in the space of the model parameters were studied. This allowed to find the model parameters that can better represent the study area. The values obtained were considered reasonable. For example, it is observed that the longer memory of the catchment is more representative of the study catchments, which are the same results as when analyzing the meteorological phenomenon causing the floods. Further, the values obtained for the regional constant, parameter modifying the initial abstraction of the catchment, were found to be smaller than the original ones obtained for United States catchments, which agrees with other studies in European catchments.

Shiplifts are one of the main types of navigation structures in canals and high dams in natural rivers.

Looking into the future, (massive) hydraulic structures face a not inconsiderable number of challenges that need to be overcome.

Proceedings Online: https://doi.org/10.1007/978-981-19-6138-0

A ship in a lock chamber is exposed to forces acting on the hull during the filling and emptying processes. These forces accelerate the ship and lead to a displacement. To avoid a collision of the ship with the lock structure, it is moored with mooring lines, which can be strained up to a certain breaking load. The force acting in the mooring lines is called the mooring line force and must be distinguished from the ship force. If the mooring line force exceeds the breaking load, the mooring line will fail and the tension energy will abruptly be transformed into kinetic energy. A snap-back of the mooring line ends can produce great forces and the mooring staff is at risk for major injuries. Furthermore, the ship will start to move and could damage the structure and itself. Thus, the mooring line force must be limited during the locking process. The mooring line force depends on the ship force and, furthermore, on the properties of ship and mooring lines. Due to the number of possible parameter combinations the given ship force alone might not be sufficient to judge on the mooring line safety. In this paper a statistical approach to determine the relations between mooring line configuration, mooring line forces and ship force based on Monte Carlo simulations is shown.

Working with Computational Fluid Dynamics (CFD) can produce numerous datasets, which contain different physical parameters and study settings. Management and dissemination of such data benefits greatly from a comprehensive data description (metadata), ideally a specialized Metadata Information System (MIS), and adequate long-term storage (data warehouse). To avoid the manual creation of rival metadata, an automation method has been developed, which adds metadata automatically by the simulation and post-processing programs. The automation method described here is an example for data curation suitable for a professional work environment. This method begins with the collection and creation of metadata and ends with the dissemination and publication of the data. This procedure reduces the challenging amount of tedious and error-prone workload, avoids redundancy, enhances efficiency, and is thus a means of quality assurance. Basis for the automation process is an open-source metadata information system (MIS) which has been adapted to the techno-scientific demand of simulation metadata. It stores the metadata in an SQL database and provides Open Geospatial Consortium (OGC) compliant services and communication interface. A hierarchical metadata management concept was initiated for efficient management of numerous datasets. Subsequently, the metadata validation and dissemination are automated via a middleware, which compiles metadata in an XML file, imports the metadata into the MIS and transfers the data to a long-term repository via a Representational State Transfer (REST) interface. Finally, the data and metadata are interlinked and published.

The PIANC InCom/EnviCom Working Group 236 was established in early 2021 to develop PIANC guidelines for improving navigability conditions on natural or quasi-natural rivers, while maintaining morphological processes and natural river form and function. Its key objectives include: 1) development of guidelines to improve and maintain the navigability in natural rivers; 2) assess the sustainability of river training works designed to improve the navigability; 3) assess the sustainability of dynamic river management (monitoring and shifting of navigation aids to adapt the navigation channel to the river dynamics); 4) highlight the technical, operational, economic and environmental considerations for navigation in natural rivers compared to that in regulated rivers and canals; and 5) improve the understanding of the physical processes in natural rivers, developed with or without river training works. The developed guidance includes a planning framework for developing a navigability improvement masterplan for a natural or quasi-natural river system, and the integrated and adaptive management strategies that can be applied at a system scale. Specific interventions and measures have been identified to meet the dual goals of maintaining morphological river function and improving navigability conditions. These measures include dynamic charting; morphological dredging and disposal management; Temporary, Adaptable, and Flexible Training Structures (TAFTS); riverbed armoring and sediment nourishment; rock excavation; meander cutoffs and oxbow development; localized traditional river training structures; and channel closure structures. The impacts and strategies for mitigation associated with some of the measures are analyzed and discussed. Finally, the continual monitoring, management, and operational tools available for improving navigability in a morphologically active river system is presented. It is recognized that natural and quasi-natural rivers will typically be more fluvially active and dynamic than systems that have used traditional methods for navigability improvements including heavily trained rivers or systems with locks and dams. These unrestricted and unconfined river systems, therefore, will require new and innovative strategies to monitor the fluvial and geomorphic changes of the system in order to inform managers and navigators of the river. Case studies are presented that include the Madeira River (Brazil); Magdalena River (Colombia); Niger Delta (Nigeria); Yangtze River (China); the Brahmaputra-Jamuna River (India); and the Red River (Vietnam).

One of the challenges in assessing the load-bearing capacity of existing solid hydraulic structures is the formal verification of concentrated loads for plain concrete. Due to the age bandwidth of such structures in Germany, this applies to hundreds of cases and especially to older structures of rammed concrete. Typical examples of components subjected to partial loads are found at weir pillars: e.g. support niches of inspection closures. Although they cannot be formally verified using the current regulations, the BAW Code of Practice “Evaluation of the load bearing capacity of existing solid hydraulic structures” (TbW) allows more detailed investigation methods to be applied, e.g. the use of non-linear probabilistic calculations. The principle research motivations are a higher loading capacity by numerical simulations with a more realistic material model compared to the usual linear calculations and a higher loading capacity by reproducing a “natural” bandwidth of material characteristics in these simulations. The aim of the current research project is the development and standardisation of the numerical simulations for such a verification procedure and its underlying safety concept by a classification of structural markers. As a result, the necessity of complex reinforcements for such structures could be assessed. The paper introduces the research concept and addresses the investigation steps regarding measured and generic 3D material distributions and FEM representation specifics as the material model. Furthermore, the preparation of the stochastic analysis is introduced by a demonstration model: The resulting hundreds to thousands of simulations of individual cases enable the stochastic analysis of metamodels to deduce general probabilistic results. Prospectively, the demonstration model will be transferred to further component measures and compressive strength classes.

In the harbour of Hamburg a new bridge crossing the Suederelbe at Elbe km 620 has been planned. The bridge is part of the BAB26 motorway. Contracted by DEGES, a German company for highway planning and design, BAW determined the ship impact loads on the basis and methodology of EN 1991-1-7 (2006) on a site - specific basis, BAW (2016). The Suederelbe Bridge crossing will have a length of 695,60 m with main span bridging the fairway over 350 m. The pylon height of the main piers is planned to be 150 m. The clearance height of the Suederelbe crossing should be 53 m above sea level. The two pylons and main piers of the Suederelbe bridge crossing, which are to be positioned close to the bank, are at risk of ship impact. About 6,000 seagoing vessels up to 33,000 dwt are passing the future bridge. Fleet structure, ship passages, speeds, accident rates and nautical conditions were analysed and ship impact loads for the piers and protective structures were determined using a load model on one hand and a collision model on the other hand. Load and collision model are probabilistic and based on corresponding distributions of the decisive influencing parameters, whereby this approach represents state-of-the-art technology. Based on the collision model, the average time that the eastern pylon is being impacted is expected to be 470 years, while the average time for the western pylon is expected to be 1,240 years.The impact loads for the east pylon are dynamic loads with FFdyn = 17.5 MN for frontal impact and FLdyn = 4.0 MN for lateral impact. Out of the models the impact load can be determined as dependent on the distance of the piers (pylons) to the fairway center line. The variation of the span distance of the pylons show the plausibility of the developed and used modelling.

This article addresses the applicability of experimental methods for the evaluation of concrete durability on localized structural weaknesses posed by joints. Three different types of exposure are analyzed: chloride penetration, carbonation, and freeze–thaw attack. First, established experimental methods for the characterization of the durability of plain concrete are presented and their general applicability on concrete joints is discussed. The experimental program focuses on the execution of selected tests on laboratory specimens with and without joints. Indicator tests for both chloride penetration and carbonation are generally feasible, but require attention to specimen preparation. Rapid chloride migration yielded inconclusive results, while uniaxial chloride diffusion coefficient of concrete joints cannot be determined because of the areal extent of profile grinding. For the same reason, the characterization of the resistance to freeze–thaw cycles through surface deterioration is not applicable for concrete joints. The structural damage was instead successfully qualified through direct tension tests.

When designing navigation locks, several parameters must be considered: Apart from the construction and operation costs also the operation speed and lockage safety must be considered. The safety of the lockage is often expressed in terms of the acceptable ship forces. Traditionally, apart from physical models different kinds of numerical models are used to determine the speed and safety of operation: During the predesign phase often simple analytical approaches are used, while in later design phases more sophisticated one- or three-dimensional numerical models or physical models are used independently or in a hybrid modelling approach. With these models the flow rates, the development of the water levels and the resulting forces on the ship can be computed or measured. While the application of three-dimensional numerical models for the lock filling process was in the past limited to very few and extraordinary projects, nowadays their application becomes more and more engineering practice. Here we are giving an overview of the numerical modelling methodologies and are presenting the state-of-the-art for three-dimensional numerical models.