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Drainage works using culverts are potentially affected by local scour risk. Local scour process is a complex phenomenon affected by many factors. Most of them have been analyzed in previous studies, either individually or in small groups. However, no fully joint analysis has been developed so far. Since the number of factors and interactions is high, the main objective of this work was to determine which of them best represents the dimensions of the scour hole and the embankment undermining. 80 experiments have been designed and developed and studied by ANOVA techniques. These results highlight the effect of wing walls with a floor slab at the outlet and the inlet blockage, showing them to be of major importance. The influence of the tailwater depth and the culvert shape on the scour hole are confirmed as relevant factors, as well as the presence of wing walls. Some interactions have been identified as relevant. The main outcome of this work is the set of factors and interactions that has significant impact on local scour process occurring beside a culvert. This selection is the basis for performing further experimental work in the future to obtain a general empirical law that quantifies this kind of local scour.

The main stage of the survey is a field survey as a result of which a decision is made on the need for reconstruction work. The object of the study is culverts on the section of the Ust-Ishim-Zagvazdino highway, which runs along the River Irtysh. During the inspection, defects in the culverts were identified and decisions were made for reconstruction. Calculations of the new pipe diameter were carried out and modern materials were selected.

Buried rigid box culverts are widely used in transportation and water structures and are often constructed beneath high embankments. Due to the stiffness contrast between the rigid structure and surrounding backfill soil, the soil column directly above the culvert experiences smaller settlement than adjacent soil columns, which may result in stress concentration and increased vertical pressure on the culvert. The induced trench installation (ITI) method was introduced to mitigate this problem by adopting a compressible inclusion above the structure to initiate positive soil arching and redistribute the loads away from the culvert. This study investigates the influence of expanded polystyrene (EPS) geofoam inclusion parameters on the structural behavior of buried rigid box culverts through a series of experimental tests. Eleven reduced-scale laboratory model tests were conducted, including one reference test without EPS and ten tests incorporating EPS inclusions with varying densities, thicknesses, widths, and installation locations. Static surface loading ranging from 20 to 140 kPa was applied using a rigid footing system, while vertical pressures within the backfill were monitored using miniature pressure sensors installed above and beside the culvert. The results show that EPS inclusion significantly alters the load transfer mechanism within the backfill and promotes the development of positive soil arching. Among the investigated parameters, EPS thickness had the most pronounced influence on stress reduction, increasing the pressure reduction efficiency from approximately 50% to about 70% as the thickness increased from 2.5 cm to 10 cm. A lower EPS density also slightly enhanced stress reduction due to its higher compressibility. The findings demonstrate that properly configured EPS geofoam inclusions can effectively reduce vertical stresses acting on buried rigid culverts and improve their structural performance under embankment loading conditions.

To investigate the influence of the culvert cone angle and the angle of the mouth on the aerodynamic performance of the culvert coaxial twin rotor and its mechanism, the quasi-steady numerical simulation of the flow field of the culvert coaxial twin rotor under a hovering state was carried out based on the Reynolds mean Navier-Stokes (RANS) equation and the multiple reference coordinate system method (MRF). The influence of cone angle from -6° to 9° and lip deflection angle from -20° to 30° on the aerodynamic performance of coaxial double-rotors with ducted passages is analyzed. The results show that the contractile culvert can generate a large gain lift force, which is conducive to improving the aerodynamic efficiency of the system. The inward deflection of the lip obstructs the flow of air into the culvert, which will worsen the local aerodynamic environment and lead to serious air separation, increasing the power consumption of the system. However, the structure of the outward deflection of the lip (open culvert) better complies with the flow trend of air, helps to reduce aerodynamic interference, and improves the additional lift of the culvert, which is beneficial to improving the aerodynamic performance of the system.

The article experimentally studied the dynamics of sediment inflow into the fore chambers of pumping stations, revealed the intensity of silting, which affects the reliability and operation of the pumping station, and developed recommendations for improving its efficiency. The hydraulic parameters of the flow were evaluated by increasing the culvert capacity of the canal bed and ensuring a guaranteed flow of water to the pumping station with a minimum amount of sediment. The purpose of this work is to assess the state of its culvert capacity based on the results of field studies, which represent the water supply from the pumping station of the Karshi main canal.

This study presents a finite difference model for analyzing ground stability and settlement of twin circular culverts in undrained clay. The model is verified through simulations of soil movement and relaxation around a tunnel-boring machine's shield. Stability numbers and ground settlement are evaluated across various culvert geometries and soil ratios and compared to rigorous solutions and previous models. The settlement data obtained is used to determine inflection point parameters for practical culvert design, considering dimensionless ratios. The findings highlight the importance of precise design methodologies that consider soil properties and geometry. The finite difference model proves to be a valuable tool in culvert design, providing accurate analysis of stability and settlement characteristics. The presented design figures and regression equations serve as practical tools for engineers in designing stable twin circular culverts in undrained clay. The study emphasizes the need to carefully consider soil properties and geometry for successful culvert design. In conclusion, the finite difference model offers insights into ground stability and settlement of twin circular culverts. The presented design figures and regression equations support engineers in making informed design decisions, ensuring the stability and long-term performance of culverts in undrained clay conditions.

This article presents guidelines for assessing the optimal dimensions of forest road pipe culverts, based on input of actual and experimental data to standard engineering techniques. In doing so, we assess the need for (i) changes in the parametrisation of inputs (i.e. culvert micro-catchment dimensions, rainfall and resultant culvert flow, and culvert flow rates during culvert hydraulic dimensioning), and (ii) the need to redesign culvert outlets in relation to flow speed. Our results demonstrate that values for most inputs presently used under current technical practice for forest road pipe culvert sizing are significantly higher than those achieved under experimental conditions. The data on outlet flow velocities strongly suggests that strengthening of culvert outlet aprons will be crucial for their future operation.

The flow being discharged from the culvert during flood events leads to significant alterations in the topographical features of the downstream bed. These modifications, manifested as scouring, have the potential to compromise the structural integrity of the culvert. It is therefore greatly important to investigate the factors affecting the extent and the form of scouring downstream. One effective approach to minimizing flow energy, thereby mitigating downstream scour, is the implementation of artificial roughness within the culvert structure. This study examined influences of a box culvert’s longitudinal gradient on the topographical variations of the bed downstream in relation to the artificial roughness. Moreover, the outcomes derived from various slope configurations were analyzed in conjunction with scenarios where the culvert was integrated with artificial roughness components and positioned horizontally with a zero slope. A key finding of this research was that the maximum slope examined had a more significant effect on diminishing the maximum scour depth downstream of culvert than the other slopes analyzed did. By inclining the culvert bed, the maximum sedimentation height in the downstream areas was enhanced in comparison to the horizontal culvert configuration. Furthermore, the configurations incorporating an artificial roughness with a height equivalent to 0.13 times the height of the culvert opening demonstrated a significantly advantageous impact toward mitigation of the maximum scour depth. The sedimentation volume and area downstream were observed to undergo reductions in instances where the longitudinal slope of the culvert was greater, in comparison to scenarios with other slopes.

Foamed concrete is widely employed in highway transition sections, due to its lightweight, high-strength, and effective settlement control. It is crucial to investigate its dynamic response linked to the traffic-loading influence zone of embankment and transition section smoothness. In this study, in-situ truck tests were conducted in the road-culvert-bridge transition section to obtain the spatio-temporal response patterns. Based on the vertical response, the influence zone was ascertained. Depending on the longitudinal response, the smoothness was evaluated by equivalent dynamic stiffness (EDS) and acceleration variation rate (AVR). Furthermore, the response discrepancies of embankments with different fillings were compared. Findings reveal exponential attenuation of dynamic stress and acceleration with increasing depth. The acceleration and dynamic displacement exhibit U-shaped patterns in the culvert subsection and abrupt changes in the bridgehead subsection. The influence zone determined by the acceleration attenuation coefficient method, dynamic stress attenuation method, and stress diffusion angle method was 1.55 m, 2.05 m, and 2.89 m, respectively. The maximum disparity in EDS occurs at the culvert subsection and bridge abutment, and the AVR ranges from 0 to 0.52 s −2 . Moreover, 94.1% attenuation of the dynamic stress occurred within the 1.5-meter foamed concrete embankment under the setting of 100 kN-60 km/h.

An increase in the fill height of buried box culverts leads to an increase in the thickness of the slab and wall, as well as in the number or size of longitudinal slab reinforcements required to resist flexure. This geometrical configuration imposes a shear behavioral mode. This study focuses on determining the shear strength of reinforced concrete (RC) box culverts with uniformly distributed load at the top slab. A framework, consisting of several subframes, was designed to convert the single displacement applied at the top of the framework to the equivalent uniformly distributed forces at the top slab of the culvert, allowing a displacement control analysis algorithm to be performed. To validate the loading mechanism, using the proposed framework, the load was applied on the top of an RC beam in the laboratory, and numerical studies were conducted. After validation, two sizes of RC box culverts were experimentally and numerically investigated. The results from the experimental program and verified numerical models differed from AC1 318-14 formulation for the shear strength of top slabs of RC box culverts. Keywords: box culverts; displacement control; framework; shear behavior; uniformly distributed load.