Search Results (97)

The planktonic dispersal of Limnoperna fortunei larvae and the byssal attachment of juveniles and adults make this species a major invasive biofouling species in water-conveyance infrastructure, while artificial hydraulic connectivity further facilitates its spread. Dense colonization can reduce conveyance capacity, increase energy consumption, accelerate structural deterioration, and impair water quality, thereby posing multiple risks to infrastructure operation. This narrative and critical review synthesizes evidence from 110 publications retained after screening 537 records retrieved from the Web of Science Core Collection up to 30 June 2026. The review characterizes the stage-specific progression of L. fortunei biofouling from propagule input and early settlement to mature fouling and post-treatment residual risks. It compares the applicability of eDNA/qPCR assays, conventional field surveys, and remotely operated vehicle (ROV)-based image inspection, and evaluates the effectiveness and operational limitations of physical, chemical, coating-based, and biological control measures across different risk stages. Current management often targets individual stages, with limited linkage between monitoring results and subsequent intervention. Accordingly, we propose a risk-oriented decision pathway that integrates early warning, settlement confirmation, fouling-load assessment, targeted removal, and post-treatment verification while accounting for hydraulic safety, water-quality constraints, and asset accessibility. By aligning management actions with biofouling stage and asset condition, this framework provides a basis for more sustainable operation and maintenance of water-conveyance systems. Full article

Culverts are widely used to provide crossings over small rivers and can strongly influence flood hydraulics by controlling upstream water levels. During high flows, insufficient conveyance may cause pressurization and overtopping, with important implications for flood hazard assessment. Although computational fluid dynamics (CFD) is increasingly applied to investigate these complex hydraulic processes, systematic evaluations of its performance remain limited. This study addresses this gap by validating a three-dimensional CFD model against previously published laboratory experiments for culvert-only, weir-only and combined culvert–weir configurations under both steady (rising and receding discharge sequences) and unsteady flow conditions. Beyond benchmark validation, diagnostic analyses examined inlet region mesh resolution, inflow ramp history and turbulence closure, together with the associated outlet ventilation and attachment mechanisms. The model reproduced upstream water levels with mean absolute relative error (MARE) values ranging from 0.90% to 5.42% and captured the main stage–discharge relationships across the tested configurations. However, the experimentally observed transition from partially full to pressurized flow in the combined culvert–weir configuration was not reproduced consistently. The diagnostic analyses showed that inlet resolution influences entrance losses and post-submergence headwater, inflow history alters outlet attachment and ventilation and turbulence closure affects barrel filling and air-pocket morphology. The results indicate that CFD can reproduce water level and overtopping responses well when carefully configured, while regime transition prediction remains more uncertain because of its sensitivity to ventilation and discharge history effects. Full article

Mesh resolution is a central source of numerical uncertainty in two-dimensional flood modelling because it controls terrain representation, wetting–drying transitions, computational cost, and the transferability of calibrated parameters. Yet controlled evidence remains limited on whether two widely used solvers exhibit the same resolution response patterns across flood magnitudes. This study compares calibrated model configurations developed in HEC-RAS 2D version 7.0 and SMS 13.0–TUFLOW Classic for a mountainous to low-gradient reach of the Little River, Tennessee, USA, using identical terrain, land cover roughness, and hydrological boundary data. The models were calibrated with the 6–11 April 2025 event and independently validated with the 11–16 March 2026 event. A factorial experiment comprising two models, five cell sizes (15–55 ft), and five flow conditions (the observed event and Q₅₀, Q₁₀₀, Q₂₀₀, and Q₅₀₀ design floods) resulted in 50 simulations. The study simultaneously evaluates resolution sensitivity within each calibrated model and inter-model convergence under a common scenario matrix. Inundation extent was most resolution-sensitive during the lower-magnitude observed event, whereas inter-model extent differences decreased as flood magnitude increased. Outlet hydrographs and peak discharges were comparatively stable, but local water-depth distributions became less consistent as the mesh was coarsened, particularly in SMS-TUFLOW. HEC-RAS retained greater depth consistency, plausibly because its sub-grid property tables preserve cell-scale volume and conveyance information. Overall, mesh adequacy was output- and solver-specific, indicating that grid selection should be based on the intended hydraulic output and supported by explicit spatial stability testing. Full article

Hydraulic structures disturb natural flow patterns, reducing water conveyance efficiency and increasing hydraulic energy losses, thereby affecting the sustainable management of water structures. Entrance-zone geometry, particularly upstream wing-wall configuration and canal inside slope, plays a critical role in controlling flow behavior, energy dissipation, upstream afflux, and hydraulic performance. However, the coupled effects of these geometric parameters have not been systematically investigated. Therefore, this study employed a validated HEC-RAS model to evaluate the combined influence of canal inside slope and upstream wing-wall configuration on the hydraulic performance of irrigation water structures and to support sustainable hydraulic design. Four wing-wall configurations (box, broken, curved, and splayed) and three canal inside slopes (1:1, 3:2, and 2:1) were analyzed under a fixed contraction ratio of 0.6 and upstream Froude numbers ranging from 0.12 to 0.18 under steady subcritical flow conditions. The model was validated against measurements from a 1:10 laboratory flume, demonstrating excellent agreement, with an average variation of 5.75% and coefficients of determination (R²) ranging from 0.97 to 0.99. Gradual entrance transitions significantly improved hydraulic performance by reducing flow disturbances and enhancing flow uniformity. For a canal inside slope of 1:1, the curved wing-wall configuration reduced relative heading-up and energy loss by 18.02% and 46.83%, respectively, whereas the splayed configuration achieved the best overall performance, with corresponding reductions of 27.63% and 73.11% compared with the conventional box configuration. Furthermore, dimensionless predictive equations were developed for the principal hydraulic performance indicators, achieving R² values of 0.96–0.99 and RMSE values of 0.001–0.01. The proposed framework improves water conveyance efficiency, minimizes hydraulic losses, and provides a validated, cost-effective numerical tool for evaluating alternative design scenarios, reducing reliance on extensive physical experimentation while supporting sustainable irrigation structures and long-term water resources management. Full article

Contemporary approaches to urban water management increasingly rely on concepts such as Nature-Based Solutions (NBSs), Green Infrastructure, and Blue-Green Infrastructure. Although these frameworks have gained broad acceptance, their typological character provides limited guidance for project-oriented decision-making, as they primarily describe infrastructure types rather than their functions within integrated hydrological systems. To address this gap, this study proposes a complementary functional-operational framework for interpreting ecological infrastructures in urban flood mitigation. Employing a qualitative comparative case study methodology, we analysed four diverse international models—the Dutch Water Squares (Rotterdam), Tokyo’s underground flood control system, Copenhagen’s Cloudburst Management Plan, and Singapore’s ABC Waters Programme—to examine the systemic interaction between grey, green, and blue infrastructures at different watershed scales. The results indicate that flood mitigation effectiveness depends less on the predominance of a single infrastructure type and more on the functional coupling among them. Specifically, three primary functions were identified: rapid conveyance (grey infrastructure), infiltration and thermal regulation (green infrastructure), and dynamic storage and biodiversity support (blue infrastructure). Despite the contextual limitations and varying scales of the selected cases, blue infrastructure universally emerges as a systemic buffer that enhances urban resilience by regulating excess volumetric flows. Ultimately, the proposed framework introduces an actionable interpretative layer that complements existing typological classifications, providing planners and urban designers with a robust, scalable basis for implementing integrated ecological infrastructures. Full article

Complex water conveyance systems often involve mixed flow conditions comprising pressurized pipe networks and free-surface open channels. Every single model has its limitations in long-distance and complex water transfer projects; coupling different models can leverage their respective advantages. For this reason, this study proposes an integrated modeling framework that couples the Storm Water Management Model (SWMM) and Environmental Protection Agency Network Evaluation Tool (EPANET) models to simulate water quality in pressurized–unpressurized coupled systems. Taking the typical Yin Chao Ji Liao water diversion project as a case study, total nitrogen (TN) and total dissolved solids (TDS) were selected as representative pollutants. A total of 32 simulation scenarios were systematically evaluated across four concentration levels at four distinct monitoring points. During this synthesis, key emergency response indicators, specifically T0 (optimal gate-opening time) and T2 (drainage operation duration), were quantified. The results indicate that pollutant dispersion in the unpressurised tunnel section is primarily governed by pollutant loading, whereas in the pressurised pipeline section, it is controlled by flow velocity and pressure differentials. High-concentration pollution in the tunnel section allows for a relatively longer emergency response time (T0 = 453 min). In contrast, due to rapid transport in the pipeline section, emergency operations must be completed swiftly (≤30 min). This coupled approach effectively addresses the challenge of water quality simulation in cross-regime conveyance systems. Future research will focus on integrating real-time sensor monitoring data with this coupled model to further optimize automated early warning protocols for long-distance diversion projects. Full article

Pumped hydro storage is a well-established and reliable form of energy storage, with construction scale expanding steadily in recent years. Underground cavern excavation is an indispensable part of pumped storage construction, while sustained cavern inflow poses potential threats to engineering and regional water security. This study first summarizes the hydrochemical characteristics of cavern inflow from 62 pumped-storage projects in China. Combining field investigations, water pressure tests, hydrochemical analyses, and multi-method inflow forecasting, the study further discusses the cavern inflow features of two typical projects under different climatic environments. The results indicate that across the 62 projects, total dissolved solids (TDS) in inflow water range from 21.0 to 4270.7 mg/L, with pH values of 6.7–8.3, and are dominated by HCO₃-Ca type. Moving from humid toward arid regions, TDS shows a continuous increase, while pH exhibits no significant variation. At the Shanshan site, controlled by evaporation, silicates weathering and evaporite dissolution, cavern inflows are dominated by high-salinity SO₄-Mg type water with pronounced SO₄²⁻ enrichment. Predicted inflows of the underground powerhouse and water conveyance tunnels are 1247.96–5542.97 m³/d and 105.85–211.69 m³/d, respectively. The Ningshanbei site, located in the humid area, is characterized by low-salinity HCO₃-Ca freshwater controlled by carbonate dissolution, with a high conveyance system inflow of 2914.71–3413.91 m³/d. The two sites differ markedly in recharge conditions, inflow characteristics, and water quality, requiring site-specific water management. This study provides engineering references for inflow hazard control, groundwater resource management, and ecological protection in pumped-storage projects across different climatic zones. Full article

With the vigorous development of offshore energy and mining, offshore fracturing and deep-sea mining necessitate the ship-to-ship and platform-to-ship transfer of solid particles via floating hoses. However, traditional floating hoses designed for oil transportation are inadequate for the long-term and stable conveyance of granular materials, as solid particles are prone to deposition and blockage under excessive bending. Additionally, in large-scale offshore fracturing operations, tension fluctuations in high-pressure hoses accelerate hose wear and compromise structural integrity. To address these challenges, this study proposes a systematic framework integrating neural network prediction with a feedforward–feedback composite control strategy. Spatial Attention–Convolutional Neural Network (SA-CNN) achieves the highest prediction accuracy and the strongest generalization capability across all operating conditions. Then, a feedforward–feedback composite control strategy is formulated, where the feedforward component is derived from SA-CNN predictions and the feedback component is provided by a PID controller, with an adaptive weighting mechanism adjusting their contributions based on prediction confidence. A curvature safety constraint is also incorporated to prevent excessive bending. The results show that the composite control strategy achieves the highest peak tension reduction, while achieving the lowest RMSE. Unlike pure PID, which introduces severe oscillations, the composite control strategy converges smoothly, confirming that feedforward prediction effectively suppresses feedback-induced oscillations. This study provides a theoretical foundation and a practical solution for the safety assurance of floating hoses in high-pressure fracturing fluid delivery applications and offshore solid particle transshipment. Full article

River crossing bridges in low-gradient floodplains can be affected by limited conveyance, backwater control, and scour-related foundation risk. This study evaluates a proposed IL 13 bridge replacement over the Mid Fork Saline River, Illinois, using HEC-RAS 1D steady-flow modeling, hydrologic inputs from USGS StreamStats for a drainage area of 236.45 mi², bridge opening analysis, multiple-opening interpretation, and HEC-18 scour assessment. Natural, existing, and proposed conditions were compared under design floods and Ohio River tailwater scenarios. The proposed bridge increased the effective waterway opening under all evaluated hydraulic scenarios, with increases of approximately 68.5–79.5% under the no-tailwater case, 76.1–76.9% under the 10-year Ohio River tailwater case, and 71.7–72.1% under the 50-year Ohio River tailwater case. Bridge opening velocity decreased by about one-third, indicating lower local hydraulic intensity and improved conveyance through the main opening. Contraction scour was not controlling, while computed pier scour decreased by approximately 8–10% and the controlling right abutment scour decreased slightly. Because empirical HEC-18 scour equations can have large uncertainty, commonly approaching an order of a factor of two in practical scour prediction, these reductions are interpreted only as comparative trends. They do not provide a basis for reducing foundation design requirements, but they indicate that the proposed replacement does not worsen the controlling scour response. Overall, the replacement improves hydraulic compatibility, reduces local hydraulic stress, and does not worsen the governing scour response. The study supports SDG 9, SDG 11, and SDG 13 in a hydraulic-infrastructure sense by promoting resilient bridge serviceability, safer transport connectivity, and adaptation-oriented flood risk assessment; however, full life-cycle carbon, cost, and network-resilience metrics were outside the scope. Full article

Aiming at the challenges of lining cracking and water seepage in water conveyance tunnels under high internal water pressure, joint waterproofing is the key to improving the structural anti-seepage performance. This paper investigates the mechanical and anti-seepage properties of joint sealing materials, as well as the stress-deformation characteristics of the anti-seepage structure. Uniaxial tensile tests, bond tensile tests, and interfacial shear tests were conducted on three types of sealants—polysulfide, polyurethane, and polyurea—to systematically obtain the fundamental mechanical parameters. The results show that polyurea has the highest ductility, polysulfide exhibits the highest tensile strength (1.27 MPa), and polyurethane presents balanced performance. The interfacial shear strength between polysulfide and concrete reaches 0.5 MPa, demonstrating outstanding bonding performance. Based on the cohesive zone model, a numerical model of the joint sealing system was established to analyze the evolution of stress and deformation under two working conditions: inner-side water seepage and double-sided (inner and outer) water seepage. The results indicate that water pressure induces stress peaks at the contact interface between the sealing material and the segment. The stress peak under internal water pressure alone is significantly higher than that under combined internal and external water pressures. Comprehensive comparison shows that polysulfide sealant offers better stability in resisting internal water pressure and controlling deformation. The selection of sealant type in engineering should consider the stress characteristics, deformation requirements, and construction conditions of different structural locations. Full article

Announcements of major transport infrastructure can reorganize land markets long before construction begins, as expectations are capitalized into prices and building decisions—with direct implications for sustainable territorial planning. This study examines the real estate response to the 2024 announcement of the Torquemada airport project in the Valparaíso Region, Chile. We assemble a high-resolution microterritorial panel at the block–semester–land-use level, integrating three Chilean administrative registers: the SII cadastre (over 100 million construction lines across 16 semestral snapshots, 2018–2025), the F2890 conveyance records (1.49 million geolocated transactions), and the daily Unidad de Fomento series. We estimate a multi-outcome spatial difference-in-differences design, complemented by an event study, land-use heterogeneity analysis, local indicators of spatial association, placebo tests, spatial-weight sensitivity analysis, and the heterogeneity-robust Callaway–Sant’Anna estimator. We find a robust increase in new-parcel construction in the zone of influence—identified by an annual event study against never-treated controls whose pre-announcement coefficients are small and trendless, in sharp contrast to the uniformly positive pre-trends of the expansion and aggregate-stock series—together with selective appreciation of non-residential uses and no detectable effect on housing value. The expansion and aggregate-stock components are not separately identified: their pre-announcement trends are strongly non-parallel, so the corresponding fixed-effects coefficients are read as design-conditional associations. The evidence supports an activation of the extensive margin (new-parcel building) rather than a recomposition away from densification. We read the evidence as the anticipatory footprint of the announcement rather than a point causal effect. Detecting this footprint before construction enables anticipatory value capture and sprawl-containment policy while the planning window remains open. Full article

Severe longitudinal vibrations and abnormal tension fluctuations in hoisting ropes pose significant threats to the safe and stable operation of mine hoisting systems. To address these issues, this paper proposes a semi-active vibration-suppression strategy combining a magnetorheological damper (MRD) with output-feedback adaptive sliding-mode control (ASMC). A dynamic model of the MRD-equipped hoisting system is developed using Hamilton’s principle. The nonlinear hysteresis of the MRD is described by a simplified extended hyperbolic tangent function model (SEHTFM), and an inverse model converts the desired control force into a feasible real-time current command. Using only displacement and velocity measurements at the conveyance–rope connection, the ASMC compensates for matched uncertainties, including boundary excitation, modeling and truncation errors, and force-realization errors. Numerical simulations compare an optimized passive viscous damper benchmark, SMC–MRD, and ASMC–MRD responses under varying payloads, accelerations, and hoisting speeds. During constant-speed operation, ASMC–MRD achieves peak reduction rates of 82.8% in dynamic displacement and 77.6% in dynamic tension relative to the optimized passive benchmark. The results demonstrate accurate force realization with small bounded tracking errors and improved robustness under variable operating conditions. Full article

Denil fishways exhibit limited passage efficiency for weak-swimming and benthic species, partly due to severe near-bed hydrodynamics generated by the sharp V-notch apex of conventional baffles. Modifying bottom geometry is a promising optimization pathway, but previous studies often lack rigorous comparison under constrained baffle openness ratios. This study employed CFD with the RNG $k-\epsilon$ turbulence model to evaluate conventional V-shaped (TDF), equivalent U-shaped (SCDF), and rectangular (RDF) baffles under a unified openness ratio. A layered hydrodynamic evaluation framework demarcated by the effective blocking height was developed to distinguish flow responses in the upper jet-dominated and lower baffle-controlled layers. Results show that the upper-layer conveyance indicators remain broadly comparable across configurations, whereas the lower-layer indicators show configuration-related differences within the tested discharge range. The RDF and SCDF reduce lower-layer mean velocity and TKE relative to the TDF baseline across the tested discharge range, with the RDF achieving the larger velocity reduction and the SCDF the larger TKE reduction. The maximum relative reduction in lower-layer TKE, approximately 22%, occurs under intermediate discharge. These results suggest that bottom baffle geometry can provide a potential means of adjusting near-bed hydraulic conditions in Denil fishways, although the ecological consequences require further verification. Full article

The beneficial utilization of small and medium floods requires a clear flood-control safety boundary before floodwater can be moderately stored and regulated as a water resource. For the Three Gorges Reservoir, a large river-type reservoir with long-distance backwater effects and tributary blocking, this boundary cannot be determined solely from the dam-front water level. This study developed a one-dimensional unsteady hydrodynamic model with dynamic roughness calibration to investigate the risk-constrained flood-season operating water level of the Three Gorges Reservoir. Typical flood events and the 20-year return period design flood were used to examine the responses of the maximum dam-front flood-regulation water level, excess flood volume, longitudinal water levels, and exceedance risk at key reservoir-area sections under different initial regulation water levels and release-discharge conditions. The results show that the Changshou reach is the main control section for high-water-level inundation risk under the study scenarios. When the initial regulation water level is at or below 155 m, the dam-front flood-regulation water level, the peak water level at Changshou, and the exceedance duration generally vary only slightly. When the initial regulation water level exceeds 155 m, these risk indicators increase markedly, indicating a reduced flood-control safety margin. Perturbation analysis further shows that the dam-front flood-regulation indicators are relatively insensitive to small roughness and dam-front boundary perturbations, whereas the Changshou water level and exceedance duration are more sensitive to roughness and flood-volume perturbations. Therefore, 155 m should be interpreted as a conservative operational reference boundary under the current design-flood framework, existing operation rules, and the assumption of no forecast-based pre-release, rather than as an absolute safety threshold. Increasing release discharge can reduce high-water-level risk in the reservoir area under preset release limits, but its practical application must remain conditional on downstream flood-control constraints and real-time flood-conveyance capacity. The results provide a hydrodynamic basis for risk-constrained flood-season operation of large river-type reservoirs. Full article

Understanding the variation law and prediction method of thermal conductivity for NaCl-bearing aeolian sand is of great significance for the thermal parameter selection and temperature field analysis of engineering structures including subgrades, foundations and lined water conveyance canals in the saline soil region of southern Xinjiang. The thermal conductivity of NaCl-bearing aeolian sand under different dry densities, moisture contents and salt contents was measured via the transient plane source (TPS) method. The variation law and corresponding influence mechanism were analyzed, and a thermal conductivity prediction model was established. The experimental results indicate that the thermal conductivity of NaCl-bearing aeolian sand increases with increasing dry density and moisture content, showing strong linear correlations with both parameters. At a salt content of 2%, the maximum increase in thermal conductivity induced by increasing moisture content reached 29.3%, which was approximately 1.53 times the increase observed at a salt content of 8% (19.17%). In contrast, the influence of salt content on thermal conductivity exhibited a nonlinear trend. With increasing salt content, the thermal conductivity initially decreased and then increased, and the salt content corresponding to the minimum thermal conductivity shifted toward higher values with increasing moisture content. Specifically, this critical salt content gradually shifted from 2% to 6%. This law reveals that the increase in dry density and moisture content improves the thermal conductivity of the soil mainly by enhancing the solid and liquid heat transfer pathways, whereas the variation of salt content is controlled by the water–salt coupling effect. The model calculation results show that the established prediction model is in good agreement with the measured experimental data (R² = 0.9674), with favorable applicability and high prediction accuracy. It can provide a reliable reference for the thermal calculation of sandy foundations and related engineering materials in saline soil areas. Full article