Journal articles: 'Large culvert'

1

Crook, Natasha, Stuart C. Cairns, and Karl Vernes. "Bare-nosed wombats (Vombatus ursinus) use drainage culverts to cross roads." Australian Mammalogy 35, no. 1 (2013): 23. http://dx.doi.org/10.1071/am11042.

Full text

Abstract:

Despite drainage culverts being numerous along highways, there is a scarcity of data evaluating their use as roadway underpasses by wildlife, including the bare-nosed wombat (Vombatus ursinus), a large marsupial that is involved in substantial numbers of vehicle collisions in New South Wales. Culvert use was measured with camera traps positioned at 19 drainage culverts along an 8-km stretch of ‘Thunderbolt’s Way’ near Nowendoc on the Northern Tableland, north-eastern New South Wales. The estimated probability of the occupancy/use of a culvert by a wombat was 0.46 ± 0.10. Culvert use was related to structural variables (e.g. diameter and length) and both the distance to the next adjacent culvert and to forest cover. This suggests that wombats readily use drainage culverts to cross under roads and that these structures could be modified (e.g. by maintaining proximate forest cover) to increase the likelihood that wombats would use them, thus reducing vehicle collisions and road mortality of wombats.

APA, Harvard, Vancouver, ISO, and other styles

2

Ford, Adam T., and Anthony P. Clevenger. "Factors affecting the permeability of road mitigation measures to the movement of small mammals." Canadian Journal of Zoology 97, no. 4 (April 2019): 379–84. http://dx.doi.org/10.1139/cjz-2018-0165.

Full text

Abstract:

Mitigation measures, such as wildlife-exclusion fencing and crossing structures (overpasses, underpasses, culverts), have been widely demonstrated to reduce the negative effects of roads on medium-sized and large animals. It is unclear how these mitigation measures influence the movement of small mammals (<5 kg). Our study has three objectives: (1) to test whether culverts improve highway permeability; (2) to determine factors associated with culvert use, such as culvert obstruction by snow; (3) to evaluate factors contributing towards fence permeability, such as the presence of a culvert, snow depth, and fence mesh size. We used snow tracking to assess the movement for four small-mammal taxa along the Trans-Canada Highway corridor in Banff National Park, Alberta, Canada. We found that the presence of a culvert within 100 m of transects significantly improved fence and highway permeability. Obstruction of the culvert entrance by snow was negatively correlated with the probability of use, and therefore, of highway permeability. Furthermore, the mesh size of the fencing did not affect fence or highway permeability. We recommend that culvert entrances be located on the outside of fenced right-of-ways to reduce obstruction by highway maintenance activities such as snowplowing.

APA, Harvard, Vancouver, ISO, and other styles

3

Ho, H. C., M. Muste, S. Plenner, and A. R. Firoozfar. "Complementary experiments for hydraulic modeling of multi-box culverts." Canadian Journal of Civil Engineering 40, no. 4 (April 2013): 324–33. http://dx.doi.org/10.1139/cjce-2012-0201.

Full text

Abstract:

Culvert design must account for a large range of flow rates but most of the time culverts convey flows that are smaller than the design flow. Repeated high flows passing through the culverts lead to a gradual increase of the sediment deposits in the culvert vicinity, eventually resulting in reduced flow and sediment capacity. Sedimentation at culverts is quite an involved process due to the combined effect of flow non-uniformity and unsteadiness, as well as of the flow–sediment interaction. This paper reports results from a series of laboratory experiments aimed at understanding the hydro and morpho-dynamic changes occurring in the vicinity of a three-box culvert. For this purpose, velocity and turbulence characteristics upstream of the culvert were mapped globally and locally during the transition from an original flatbed to equilibrium sediment transport condition using contemporary acoustics, light detection and ranging, and image-based technologies. The experimental results reveal flow complexities not currently accounted for in the design of the multi-barrel culverts, but which can be detrimental for their long-term operation. Considerations on practical approaches to efficiently model the complexities were formulated.

APA, Harvard, Vancouver, ISO, and other styles

4

Xu, Jiancong, Huihao Xue, and Guorong Rui. "Theoretical Analysis of Rock Blasting Damage in Construction of Tunnels Closely Under-Passing Sewage Box Culverts." Applied Sciences 12, no. 19 (September 30, 2022): 9875. http://dx.doi.org/10.3390/app12199875.

Full text

Abstract:

With the large-scale construction of urban traffic tunnels in China, it has become common to underpass existing buildings and structures such as sewage box culverts and pipelines using the drilling-blasting method. How to analyze accurately the blasting damage of surrounding rock and reasonably determine the safe distance between tunnel and box culvert or pipelines is an urgent issue to be solved. In this paper, the Cowper-Symonds plastic kinetic hardening model was improved using both rock initial damage degree and damage modification coefficient considering rock residual strength. The proposed model was implemented into LS-DYNA. The proposed damage model was used to evaluate the blasting construction of rock tunnels closely under-passing sewage box culverts. The results of numerical simulation using the proposed damage model shows that the blasting damage range of rock with a damage degree of more than 0.5 very significantly reduces from 1.0 m to 0.3 m as the spacing between the box culvert and the tunnel increases from 1.0 m to 4.0 m, and the evolution process of rock blasting damage can be well-presented. Moreover, the safe distance between tunnel and box culvert in blasting construction can be reasonably determined to be no less than 4.0 m. The findings in this paper could be significant for guiding the blasting construction of rock tunnels closely under-passing sewage box culverts.

APA, Harvard, Vancouver, ISO, and other styles

5

Gultom, J., Pratikso, and A. Rochim. "Floating road construction on soft soil." IOP Conference Series: Earth and Environmental Science 955, no. 1 (January 1, 2022): 012016. http://dx.doi.org/10.1088/1755-1315/955/1/012016.

Full text

Abstract:

Abstract The main problem of road construction on saturated soft soils is due to their low bearing capacity and large settlement. One of the solutions to such problems is to install piled box culverts-geofoam. In this study, the pile box culvert-geofoam was modelled as raft foundation. This experimental study was conducted by making a prototype raft file foundation gradually loaded with a maximum vertical load of 20 kN. Different thicknesses of geofoam were utilized in order to observe the influence of thickness on the settlement. Furthermore, difference in settlement is also found when the culvert was constructed with and without geofoam. Thicker geofoam was observed to result in smaller settlement.

APA, Harvard, Vancouver, ISO, and other styles

6

Zheng, Jun Jie, De Pi Luo, and Qiang Ma. "Numerical Analysis of Slab Culvert Beneath Imperfect Ditch Covered with Geogrid Layers." Applied Mechanics and Materials 71-78 (July 2011): 3338–41. http://dx.doi.org/10.4028/www.scientific.net/amm.71-78.3338.

Full text

Abstract:

The overburden of high embankment culvert is over 10 m, such high fill always leads large earth pressure on the slab of the culvert. The imperfect ditch covered with geogrid method was employed to reduce the vertical earth pressure on the slab. A series of numerical analyses were performed to investigate the load reduction effect of the imperfect ditch. In the simulation, the number of geogrid layers, the geometry of the load reduction ditches, as well as the location and the stiffness of the geogrid are investigated to analyse the influences on the vertical earth pressures. The results show that the slope angle and the height of the ditch, the plane stiffness of the geogrid have great effect on the load reduction efficiency, ditches with higher height and a slope of 90°lead to a significantly reduction on vertical earth pressures on the crown of culverts. The width of load reduction ditch, number of geogrid layers, the location and spacing of the geogrids have little effect on load reduction, the results can provide references for load reduction of slab culvert.

APA, Harvard, Vancouver, ISO, and other styles

7

Hotchkiss, Rollin H., Emily A. Larson, and David M. Admiraal. "Energy Dissipation in Culverts by Forced Hydraulic Jump within a Barrel." Transportation Research Record: Journal of the Transportation Research Board 1904, no. 1 (January 2005): 124–32. http://dx.doi.org/10.1177/0361198105190400113.

Full text

Abstract:

Riprap and concrete stilling basins are often built at culvert outlets to keep high-energy flows from scouring the streambed. Two simple alternatives to large basins are examined: a horizontal apron with an end weir and a drop structure with an end weir. The two designs are intended to reduce the flow energy at the outlet by inducing a hydraulic jump within the culvert barrel without the aid of tailwater. This research examines the jump geometry and the effectiveness of each jump type and proposes a design procedure for practicing engineers. The design procedure is applicable to culverts with approach Froude numbers from 2.6 to 6.0. Both designs are effective in reducing outlet velocity 0.7 to 8.5 ft/s (0.21 to 2.59 m/s), momentum 10% to 48%, and energy 6% to 71%. The design layouts allow easy access for maintenance activities.

APA, Harvard, Vancouver, ISO, and other styles

8

Byrne, Peter M., D. L. Anderson, and Hendra Jitno. "Seismic Analysis of Large Buried Culvert Structures." Transportation Research Record: Journal of the Transportation Research Board 1541, no. 1 (January 1996): 133–39. http://dx.doi.org/10.1177/0361198196154100117.

Full text

Abstract:

Field experience indicates that large buried culverts have suffered essentially no damage during past earthquakes when no significant permanent ground movements have occurred. These soil structures, which generally comprise steel or concrete arch members and engineered soil, may have spans of 15 m. Static, pseudodynamic, and dynamic finite-element analyses have been carried out on these structures and indicate that for horizontal seismic loading, the surrounding soil is much stiffer than the arch and results in the seismic load being taken by the soil rather than by the arch. Under vertical seismic loading, the arch is stiffer than the surrounding soil and attracts significant load, which can essentially be accounted for by increasing the unit weight of the soil in proportion to the vertical acceleration. Thrusts and moments in a 10-m concrete arch are examined under combined static and seismic loading (both horizontal and vertical). The results indicate that significant increases in thrust and moment in the arch are predicted for peak ground accelerations in excess of 0.3 g. The good behavior of these structures under such acceleration levels in California, where they are not specifically designed for earthquake forces, indicates that their static design includes sufficient reserve to prevent failure under accelerations of these levels.

APA, Harvard, Vancouver, ISO, and other styles

9

Chen, Bao Guo, Jun Jie Jiao, Ding Bao Song, and Jun Zhang. "Numerical Simulation on Soil Arch Effect and Load Reduction Mechanism Using EPS of High Fill Culvert." Applied Mechanics and Materials 701-702 (December 2014): 879–87. http://dx.doi.org/10.4028/www.scientific.net/amm.701-702.879.

Full text

Abstract:

The stress-strain relationship of EPS board was analyzed. Theoretical analysis and numerical simulation (FE ABAQUS) were conducted to investigate the load reduction mechanism using EPS and soil arch effect of high fill culvert based on the constitutive relation of EPS board. The results show that the numerical analysis results are consistent with the theory analysis. It shows that the soil arch forms over the culvert top and partial weight of the soil column exactly over the culvert has been transferred to the outer soil column via the soil arch during the yield stage of EPS board, which produce large deformation. Furthermore, the numerical simulation by using particle flow discrete element software (PFC2D) was conducted to investigate the soil arch effect over the culvert top. The research reveals that the EPS board is at elastic state and the soil arch effect on culvert top is not obvious at low fill. With the increasing of the fill over the culvert, the EPS board becomes into the yield state, the soil arch effect over the culvert increases and the earth pressure on culvert reduces gradually.

APA, Harvard, Vancouver, ISO, and other styles

10

Нarkusha, Mykola, Mykola Klymenko, and Artur Onyshchenko. "ANALYSIS OF THE TECHNICAL STATE OF HYDROTECHNICAL STRUCTURES OF TRANSPORTATION CONSTRUCTION FROM ROAD WATER PERFORMANCE PIPES FROM THE INFLUENCE OF CORROSION." AUTOMOBILE ROADS AND ROAD CONSTRUCTION, no. 111 (June 30, 2022): 164–73. http://dx.doi.org/10.33744/0365-8171-2022-111-164-173.

Full text

Abstract:

Hydrotechnical structures of transport construction from road culverts are designed for transporting and diverting water from transport structures. One of the main factors affecting the durability of a road culvert is corrosion of the metal of the pipe itself. With the increase in the number of hydraulic engineering structures of transport construction from road culverts on roads, the issue of ensuring the reliability and durability of their operation during operation becomes of particular importance, as there is a large number of deformations, as well as cases of complete destruction of pipes under embankments. World experience shows that corrosion damage is an extremely important problem and requires an appropriate response at a very early stage of development.

APA, Harvard, Vancouver, ISO, and other styles

11

Jia, Yu Zhuo, and Rui Li. "Ground Movements in Shield Tunneling and Impacts on Railway Culvert." Applied Mechanics and Materials 680 (October 2014): 190–93. http://dx.doi.org/10.4028/www.scientific.net/amm.680.190.

Full text

Abstract:

The excavation of the tunnel will inevitably cause the displacement of soil layer, and then further threatens the safety of high-speed railway operation. Under the engineering background of high-speed rail’s box culvert, using the technique of MIDAS/GTS, the establishment is based on 3 d finite element model of tunnel, soil mass and box culvert, to analyze the effects of box culvert settlement that led by shield tunnel excavation. The research indicates that tunnel excavation causes settlement of box culvert to some large extents, the soil mass should be reinforced to ensure the safety of the high-speed railway operations during the shield construction.

APA, Harvard, Vancouver, ISO, and other styles

12

Webb, Mark C., Ernest T. Selig, Jeanne A. Sussmann, and Timothy J. Mcgrath. "Field Tests of a Large-Span Metal Culvert." Transportation Research Record: Journal of the Transportation Research Board 1656, no. 1 (January 1999): 14–24. http://dx.doi.org/10.3141/1656-03.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Wang, Hao, Wei-Min Qin, and Yu-Yong Jiao. "Stability assessment for highway with large-span box culvert jacking underneath: a case study." Canadian Geotechnical Journal 50, no. 6 (June 2013): 585–94. http://dx.doi.org/10.1139/cgj-2012-0334.

Full text

Abstract:

A case study of a double-cell, large-span prefabricated reinforced concrete box culvert with a total length of 52 m, a width of 46.8 m, and a height of 9.3 m, which passes beneath the Beijing – Hong Kong –Macau highway, is presented. The culvert is embedded in silty sand and silty clay at a depth of 1.2 m. To ensure the safety and normal operation of the highway, hydraulic jacking with the protection of a pipe roof was adopted for this project. This paper introduces the construction scheme in detail. A three-dimensional numerical simulation of the responses of the highway under which a wide box culvert jacking passes was conducted. The monitoring results on the highway as well as the actual construction process and problems encountered were analyzed. The different development characteristics or trends for the settlement and horizontal displacement of a highway surface are presented. In addition, this paper discusses the reasons for the large deformation of the highway surface as well as proposes reasonable suggestions.

APA, Harvard, Vancouver, ISO, and other styles

14

McGuigan, Benjamin L., and Arun J. Valsangkar. "Field monitoring and analysis of twin 3660 mm inside diameter induced trench culverts installed under 21.7 m of fill." Canadian Geotechnical Journal 48, no. 5 (May 2011): 781–94. http://dx.doi.org/10.1139/t11-002.

Full text

Abstract:

Although several induced trench field instrumentations have been reported in the literature, none have been for twin culverts. This paper describes a field instrumentation of twin 3660 mm inside diameter concrete culverts installed in an induced trench under 21.7 m of fill. Earth pressures were measured at the crown, shoulder, springline, haunch, and invert locations. Average earth pressures measured at the crown and springline were 0.67 and 0.32 times the overburden, respectively. Due to the large culvert size, proper compaction in the haunch regions was not achieved and the bedding was lightly compacted for constructability reasons. These factors resulted in high earth pressures at the inverts (greater than approximately 1400 kPa) and low pressures at the haunches (32–165 kPa). Numerical modelling was used to determine a vertical earth load of 0.87 times the soil prism load. The twin induced trench condition resulted in vertical earth loads 6% higher and 30% lower than the single induced trench and twin positive projecting conditions, respectively. The induced trench method therefore appears to be a viable installation option for large-diameter twin culverts, provided that issues related to bedding and constructability are addressed.

APA, Harvard, Vancouver, ISO, and other styles

15

Xu, Shiqiang, Chaoran Chen, Fu Xu, Jie Li, Zhipeng Zhang, Tianyu Xu, and Linxuan Zhu. "Modeling Analysis of the Upper Limit Water Level Mechanism in the Upstream Reservoir of a Dam Embankment." Advances in Civil Engineering 2020 (November 29, 2020): 1–13. http://dx.doi.org/10.1155/2020/8850681.

Full text

Abstract:

The dam embankment (DE) is a highway structure used in the Loess Plateau to integrate the functions of a highway embankment and a dam. This paper studies the upper limit water level mechanism of the reservoir in the upstream of the DE to determine the criterion for setting upper culverts on the DE. A reservoir model is first established, and then the replenishment and loss of the reservoir water is simulated. The principle of water balance is employed to obtain water level formulas for the reservoir. Finally, an engineering example is used to verify the upper limit water level mechanism. The results show that the water level of the reservoir fluctuates near an ideal balance water level and an upper limit water level exists. Moreover, the upper limit water level has no relation to the water storage time, and is only related to the reservoir shape with big upper and small bottom, the small amount of water entering the reservoir each year, and the large water loss caused by evaporation and leakage. The upper culvert setting criterion is obtained through the upper limit water level mechanism, and it will provide important reference significance for the necessity of the DE culvert setting.

APA, Harvard, Vancouver, ISO, and other styles

16

Byrne, P. M., T. Srithar, and C. B. Kern. "Field measurements and analysis of a large-diameter flexible culvert." Canadian Geotechnical Journal 30, no. 1 (February 1, 1993): 135–45. http://dx.doi.org/10.1139/t93-012.

Full text

Abstract:

This paper describes field measurements and analysis carried out on the Elkhart Creek soil–arch culvert structure in British Columbia, Canada. The structure has a span of 13.4 m, a rise of 7.3 m, and a soil cover of 9.6 m. The original structure collapsed during backfilling in October 1987. A new structure of the same design was built in the fall of 1989, and because of controversy regarding the design thrust value, it was instrumented to measure thrust and displacements in the arch. Displacements and stresses in the soil were also measured. The measured thrust values were much lower than expected and indicated that significant positive soil arching occurred, similar to that observed at the Vieux Comptoir soil–stucture in Quebec in 1975. A nonlinear finite element analysis of the soil–structure system was carried out simulating the construction procedures used, and the computed response was compared with the measurements. The computed and observed responses were in reasonable agreement in all aspects, namely thrust, displacements, and soil stresses, provided an allowance was made for slip at the bolted connections. Key words : culvert, finite element, arching, stress, displacements.

APA, Harvard, Vancouver, ISO, and other styles

17

Brachman, R. W. I., I. D. Moore, and A. C. Mak. "Ultimate Limit State of Deep-Corrugated Large-Span Box Culvert." Transportation Research Record: Journal of the Transportation Research Board 2201, no. 1 (January 2010): 55–61. http://dx.doi.org/10.3141/2201-07.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Chanson, H. "Hydraulics of Large Culvert beneath Roman Aqueduct of Nı⁁mes." Journal of Irrigation and Drainage Engineering 128, no. 5 (October 2002): 326–30. http://dx.doi.org/10.1061/(asce)0733-9437(2002)128:5(326).

Full text

APA, Harvard, Vancouver, ISO, and other styles

19

Chen, Shui Sheng. "Vibration Analysis of a Moving Truck on a Long Span RC Culvert." Applied Mechanics and Materials 71-78 (July 2011): 3333–37. http://dx.doi.org/10.4028/www.scientific.net/amm.71-78.3333.

Full text

Abstract:

A general numerical simulation method is presented for the analysis of the dynamic interaction problem between a large-span concrete culvert, discretized by a plane strain finite element model (FEM), and a dynamic system of vehicle traversing at various speeds. The vehicle is represented as a mass-spring-damper FEM system with seven degrees of freedom. The time-variable coupled dynamic system is solved by a step-by-step solution technique using Newmark’s integration scheme. The backfill soil elastic modulus is modeled as varying linearly with depth below the ground surface. Several numerical examples are investigated by modifying different parameters such as backfill height and road surface stiffness, respectively. The dynamic displacement response for the mid-span point of the concrete culverts is analyzed, as well as the displacement impact factor. The research results demonstrate that the impact factor changes with the vehicle speed and strongly depends on the road surface roughness conditions.

APA, Harvard, Vancouver, ISO, and other styles

20

Chu, Inyeop, Sang-Kyun Woo, Sang Inn Woo, Joonyoung Kim, and Kicheol Lee. "Analysis of Vertical Earth Pressure Acting on Box Culverts through Centrifuge Model Test." Applied Sciences 12, no. 1 (December 22, 2021): 81. http://dx.doi.org/10.3390/app12010081.

Full text

Abstract:

Due to the lack of surface space, most structures are heading underground. The box culvert is underground infrastructure and serves to protect the buried structure from the underground environments, but it has a different characteristic from other structures in that the inner space is empty. Therefore, in this study, the vertical earth pressure which is the most significant effective stress acting on a box culvert was measured by conducting a geotechnical centrifuge model test. A box culvert was installed following the embankment installation method, and the vertical earth pressure acting on it was measured considering the cover depth, gravitational acceleration, and loading and unloading conditions. The soil pressure measured was greater than the existing theoretical value under high cover depth and the unloading condition, which is considered as the variability of many soils or the residual stress acting under the loading condition. Finally, a goodness-of-fit test was conducted as a part of variability analysis. The measured earth pressure was found to be considerably larger than the existing theoretical value, and the variability was large as well. This means the existing theoretical equation is under-designed, which should be reflected in future designs.

APA, Harvard, Vancouver, ISO, and other styles

21

Parker, Bethanie A., Rodney P. McAffee, and Arun J. Valsangkar. "Field Performance and Analysis of 3-m-Diameter Induced Trench Culvert under a 19.4-m Soil Cover." Transportation Research Record: Journal of the Transportation Research Board 2045, no. 1 (January 2008): 68–76. http://dx.doi.org/10.3141/2045-08.

Full text

Abstract:

An induced trench installation was instrumented to monitor earth pressures and settlements during construction. Some of the unique features of this case study are as follows: (a) both contact and earth pressure cells were used; (b) part of the culvert is under a new embankment and part was installed in a wide trench within an existing embankment; (c) a large stockpile was temporarily placed over the induced trench; and (d) the compressible material was placed in two stages. The maximum vertical pressure measured in the field at the crown of the culvert was 0.24 times the overburden pressure. The maximum horizontal pressure measured on the side of the culvert at the springline was 0.45 times the overburden pressure. The column of soil directly above the compressible zone settled approximately 40% more than did the adjacent fill. The field results at the crown and springline compared reasonably with those observed with numerical modeling. However, the overall pressure distribution on the pipe was expected to be nonuniform, the average vertical pressure calculated by using numerical analysis on top of the culvert over its full width was 0.61 times the overburden pressure, and the average horizontal pressure calculated on the side of the culvert over its full height was 0.44 times the overburden pressure. When the full pressure distribution on the pipe is considered, the recommended design loads from the Marston–Spangler theory slightly underpredict the maximum loads, and the vertical loads control the design.

APA, Harvard, Vancouver, ISO, and other styles

22

Freeman, Mary, Duncan Elkins, Peter Maholland, Zachary Butler, Maxwell Kleinhans, Jonathon Skaggs, Edward Stowe, Carrie Straight, and Seth Wenger. "Slow Recovery of Headwater-Stream Fishes Following a Catastrophic Poisoning Event." Journal of Fish and Wildlife Management 12, no. 2 (June 9, 2021): 362–72. http://dx.doi.org/10.3996/jfwm-20-080.

Full text

Abstract:

Abstract Accidental spills of chemicals and other pollutants can decimate populations of stream-dwelling species. Recovery from such accidents can be relatively fast and complete when the affected stream reaches can be recolonized from upstream and downstream sources. However, faunal recoveries from accidental spills that extirpate populations from entire headwater streams have not been extensively documented, and understanding resilience of headwater-stream biota is relevant for assessing threats to at-risk species. We assessed recovery of fish populations in a 5.7-km-long headwater stream in the southeastern United States following a complete, or nearly complete, fish-kill caused by a chemical spill near the source of the stream. We sampled for fishes at five stream locations, two downstream and three upstream from a perched, culverted road-crossing located 2.4 km upstream from the stream mouth, over a period of 18.5 mo following the poisoning event. We observed 11 fish species, representing ≤65% of the fish species expected based on occurrences in nearby tributary streams. In postpoisoning sampling, only three of these taxa were observed upstream of the culvert; all 11 species, including the federally threatened Cherokee Darter Etheostoma scotti, were found downstream of the culvert but were mostly represented by a few, large individuals. In contrast, dead individuals of at least eight taxa including the Cherokee Darter were observed upstream of the culvert at the time of the fish-kill. These observations provide evidence of slow recovery of a headwater fish fauna, and especially upstream of a barrier to fish movement, where the recolonization sources are primarily downstream. Additional case studies may reveal whether this result applies generally to headwater streams. Slow recovery could make species that primarily inhabit or maintain greatest abundances in headwaters, including multiple at-risk fishes, particularly vulnerable to the threat of accidental spills that result in local population extirpation.

APA, Harvard, Vancouver, ISO, and other styles

23

Playdon, David K., and Sidney H. Simmonds. "Behavior of slab-stiffened culvert structures." Canadian Journal of Civil Engineering 15, no. 4 (August 1, 1988): 726–31. http://dx.doi.org/10.1139/l88-093.

Full text

Abstract:

Large span elliptical culverts stiffened over the upper portion with a concrete cap can be used economically in highway construction at locations where only a small soil cover is possible. The behavior of such structures based on analyses obtained using the finite element program ADINA is presented. Primary variables are the thickness of the concrete cap and the depth of the soil. The effects of both the construction sequence and highway loading are considered.The load-carrying mechanism for the composite structure is dependent primarily on the amount of lateral deformation permitted by the adjacent soil and the thickness of the concrete cap. It is concluded that the behavior of the structure is that of a flat arch; but, with the lateral deformations likely to occur, the concrete section should be proportioned as a simple beam. Key words: concrete cap, culverts, construction loads, deformations, finite element analysis, stresses.

APA, Harvard, Vancouver, ISO, and other styles

24

Kramer, M., W. L. Peirson, R. French, and G. P. Smith. "A physical model study of culvert blockage by large urban debris." Australasian Journal of Water Resources 19, no. 2 (July 3, 2015): 127–33. http://dx.doi.org/10.1080/13241583.2015.1116184.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

Dasgupta, Abhijit, and Bratish Sengupta. "Large‐Scale Model Test on Square Box Culvert Backfilled with Sand." Journal of Geotechnical Engineering 117, no. 1 (January 1991): 156–61. http://dx.doi.org/10.1061/(asce)0733-9410(1991)117:1(156).

Full text

APA, Harvard, Vancouver, ISO, and other styles

26

Wang, Xue Ying, Dong Xu, and Ya Jun Wu. "Strategy of Transformation on Existing Residential Buildings for Energy Saving in the North of China." Applied Mechanics and Materials 71-78 (July 2011): 3354–57. http://dx.doi.org/10.4028/www.scientific.net/amm.71-78.3354.

Full text

Abstract:

A general numerical simulation method is presented for the analysis of the dynamic interaction problem between a large-span concrete culvert, discretized by a plane strain finite element model (FEM), and a dynamic system of vehicle traversing at various speeds. The vehicle is represented as a mass-spring-damper FEM system with seven degrees of freedom. The time-variable coupled dynamic system is solved by a step-by-step solution technique using Newmark’s integration scheme. The backfill soil elastic modulus is modeled as varying linearly with depth below the ground surface. Several numerical examples are investigated by modifying different parameters such as backfill height and road surface stiffness, respectively. The dynamic displacement response for the mid-span point of the concrete culverts is analyzed, as well as the displacement impact factor. The research results demonstrate that the impact factor changes with the vehicle speed and strongly depends on the road surface roughness conditions.

APA, Harvard, Vancouver, ISO, and other styles

27

Yan, Gen Hua, Fa Zhan Chen, and Jia Dong. "Study of Flow-Induced Vibration for the High-Head and Large Dimension Gate." Applied Mechanics and Materials 170-173 (May 2012): 2027–36. http://dx.doi.org/10.4028/www.scientific.net/amm.170-173.2027.

Full text

Abstract:

In this paper study findings of flow-induced vibration of gate in the emptying culvert of Tishengqiao power station are presented. At first stage structure’s dynamic characteristics are investigated carefully using the experimental modal analysis technique, and entire structure modal information is obtained. In addition, flow pulsating pressure properties acting on the gate are investigated. Various physical values including vibration acceleration, dynamic displacement and dynamic stress caused by high velocity flow are studied. Finally gate structure’s dynamic reliability is analyzed and safety operation principle are presented.

APA, Harvard, Vancouver, ISO, and other styles

28

Liu, Li, Hong Kai Chen, and Hong Mei Tang. "Study on the Damage Mechanism of Bridge Pier and Foundation by Turbulent Debris Flow." Advanced Materials Research 228-229 (April 2011): 776–81. http://dx.doi.org/10.4028/www.scientific.net/amr.228-229.776.

Full text

Abstract:

The debris flow is the uppermost water-destroyed type of highway, which caused large direct economic loss annually in china, especially in mountainous area highway small bridges and culvert damaged seriously. This paper started from the theory of debris flow two-phase flow, it is divide turbulent debris flow into liquid and solid, and with the turbulent debris flow wash against bridge pier increased, the erode depth overpass the burial depth of foundation, base bearing capacity reduced gradually and then result bridge pier instability; in addition for the strong force of impact of debris flow resulted in resistance to capsizing weaken. The damage of bridge and culvert’ foundation mainly duo to the erosion, which lead to the erode depth overpass the burial depth of foundation, furthermore, debris flow force of impact greater then structure resistance and result the structure instability and damaged.

APA, Harvard, Vancouver, ISO, and other styles

29

Ramadan, Safwat H., and M. Hesham El Naggar. "Field Monitoring and Numerical Analysis of Large-Span Three-Sided Reinforced Concrete Culvert." Journal of Geotechnical and Geoenvironmental Engineering 147, no. 4 (April 2021): 04021008. http://dx.doi.org/10.1061/(asce)gt.1943-5606.0002489.

Full text

APA, Harvard, Vancouver, ISO, and other styles

30

Sagawa, Y., T. Katayama, T. Tsutsumi, and H. Matsushita. "Development of Large-scale Precast Concrete Skew Box Culvert with Looped Joint Connection." Concrete Journal 49, no. 3 (2011): 13–20. http://dx.doi.org/10.3151/coj.49.3_13.

Full text

APA, Harvard, Vancouver, ISO, and other styles

31

Green, Kenneth, and Nickie J. Whitehouse et al. "Castlebank Street and the origins of the Bishop's house/Partick Castle." Scottish Archaeological Journal 41, no. 1 (March 2019): 1–25. http://dx.doi.org/10.3366/saj.2019.0104.

Full text

Abstract:

Excavations at Castlebank Street, Partick between the Clyde and the Kelvin Rivers revealed some archaeological features. The earliest was a Roman/Iron Age ditch, dated to the second to third century AD. Medieval activity on the site included a large north-east/south-west oriented ditch with a culvert and a slightly later substantial stone wall. In addition, a stone-lined well was located and a small ditch with associated features in the north of the excavated area. These features spanned the beginning of the eleventh to the end of the fourteenth century. A limited range of material culture, mainly medieval and later medieval local pottery, with some glass and animal bone was associated with the fills of the larger ditch, culvert and wall. Historical research revealed a complex history surrounding the establishment of the Bishop of Glasgow's country estate and manor house (the early castle?) and its subsequent demolition. However, it has been difficult to match the archaeological evidence with the historical documentation mainly due to nineteenth century use of the area for a foundry and laundry, as well as the insertion of South Orchard Street, which did much to obliterate evidence from earlier periods.

APA, Harvard, Vancouver, ISO, and other styles

32

Fan, He, Bao Kuan Ning, and Lei Gong. "Numerical Simulation on Vertical Earth Pressure Distribution for Culverts under High Fills." Applied Mechanics and Materials 204-208 (October 2012): 577–80. http://dx.doi.org/10.4028/www.scientific.net/amm.204-208.577.

Full text

Abstract:

High fill culverts have been widely used in expressway in mountain area and problems of culverts frequently take place because of improper design including some earth-pressure calculated values conservatively or culvert type selection irrationally. FEM numerical simulation was carried out to investigate the stress state of the culvert fill. The effect of four influences on the stress state of high-filled culvert is discussed. The research results show that culvert structure type influences earth pressure distribution that arch culvert is different to slab and box culvert. Earth pressure values when boundary slope is 1:0.35 are all larger than slope 1:0. Due to arch effect and stress distributed secondly, nonlinear increased amplitude of earth pressure is reduced with fill heightening. Earth pressure of culvert top and side decreased along with culvert side wall thickness increment. The research can give some references on the design correctly.

APA, Harvard, Vancouver, ISO, and other styles

33

Beckers, Jos, Younes Alila, and Ahmed Mtiraoui. "On the validity of the British Columbia Forest Practices Code guidelines for stream culvert discharge design." Canadian Journal of Forest Research 32, no. 4 (April 1, 2002): 684–92. http://dx.doi.org/10.1139/x02-010.

Full text

Abstract:

In the stream culvert discharge design guidelines of the Forest Practices Code (FPC) of British Columbia (BC), the 100-year instantaneous flood (Q100) is assumed to be three times as large as the mean annual flood (Q2) regardless of basin characteristics and location in the province. A regional linear moment analysis of annual maximum flows is used to demonstrate that this assumption is invalid and that Q100/Q2 ratios vary substantially with basin area and climate. For the snowmelt-dominated peak flows in the Columbia and southern Rocky Mountains, Q100/Q2 decreases slightly with increasing drainage area, from 2.3 (1 km2) to 1.9 (100 km2). For the flood peaks generated by rainfall and rain on snow in coastal BC, this range is 3.12.6. In the semi-arid Interior Plateau region, variability in Q100/Q2 ratios is most dramatic. For a 10-km2 basin, the calculated Q100/Q2 ratio of 4.9 is 1.6 times the assumed factor of 3, while for a 1-km2 basin Q100/Q2 is 7.5 or 2.5 times this factor. Underestimating Q100/Q2 may lead to underdesign and early failure of road culverts, and therefore, current FPC guidelines for estimating the 100-year instantaneous flood may have serious adverse economic and environmental consequences in small Interior Plateau watersheds.

APA, Harvard, Vancouver, ISO, and other styles

34

Susanti, Irriene Indah, and Dewitri Asti Ifo HS. "Analysis of The Cost and Time Comparison of Diversion Methods and Dewatering of Box Culvert Work." Journal of World Conference (JWC) 2, no. 2 (March 31, 2020): 148–55. http://dx.doi.org/10.29138/prd.v2i2.218.

Full text

Abstract:

Low geographical conditions and flowed by many rivers and the reduction of retention ponds in Jakarta, then built a reservoir. However, during the implementation period, it was delayed by 9.74%. One of the things that can be done to overcome delays is to choose a method of implementation. The method is diversion and dewatering. The results of the analysis are expected to produce a large comparison of the costs and time of each method. From the analysis results, the cost of implementing the method of soil and rock diversion in the box culvert work is Rp. 363,935,953, while the sandbag diversion method is Rp. 332,805,831. For box culvert work using open pumping dewatering method, the required cost is Rp. 394,637,510. From these data, it was concluded that the difference in the cost of diversion sandbag and rock soil was Rp. 31,130,122. While rock soil and dewatering diversion are Rp. 30,701,557. As well as sandbag diversions with dewatering of Rp. 61,831,679. The results of observations of the implementation time obtained the conclusion that the work of box culvert with sandbag diversion method takes 35 days, and rock soil diversion 49 days while dewatering 63 days. By time comparison the sandbag diversion method is 14 days faster than rock soil diversion, and 28 days compared to the dewatering method. From these data, it can be concluded that in terms of cost and time, the sandbag diversion method is more economical and efficient than the other two methods.

APA, Harvard, Vancouver, ISO, and other styles

35

Brachman, R. W. I., T. M. Elshimi, A. C. Mak, and I. D. Moore. "Testing and Analysis of a Deep-Corrugated Large-Span Box Culvert prior to Burial." Journal of Bridge Engineering 17, no. 1 (January 2012): 81–88. http://dx.doi.org/10.1061/(asce)be.1943-5592.0000202.

Full text

APA, Harvard, Vancouver, ISO, and other styles

36

Aghebatie, Behrouz, and Khosrow Hosseini. "Computational investigation on the effects of rib on the slug flow phenomenon; using OpenFOAM." International Journal of Modern Physics C 30, no. 06 (June 2019): 1950051. http://dx.doi.org/10.1142/s0129183119500517.

Full text

Abstract:

Slug flow is a two-phase fluid flow pattern, characterized by a series of liquid slugs dispersed by relatively large air bubbles. Air bubbles produced and trapped during the slug flow phenomenon conduct to interruption in flow which induces pressure and velocity fluctuations. These effects have destructive circumstances in conduits and conveyance structures. This paper deals with studying numerically two-phase flows using computational fluid dynamic (CFD) techniques performed in OpenFOAM (an open source software) by interFoam solver. Most of the previous concerning studies on slug flow were performed in micro-channels with small scales in which the expansion of the air bubbles was negligible. By contrast, we investigated the systems with large pressure drops which conduct to abrupt increases on the volume of air phase. The slug flow phenomenon could be created by introducing air and water with different velocities at inlet of a culvert with air to water velocity ratio varied from 1.1 to 34. First, this study focused on temporal and spatial variations of pressure and velocity along the culvert. After that, by dimensional analysis, the nondimensional parameters influencing the slug flow phenomenon are extracted and analyzed. Finally, different strategies for reducing the destructive effects of slug flow, including the shape and location of ribs, are evaluated and the best strategy is proposed.

APA, Harvard, Vancouver, ISO, and other styles

37

Asp, Olli, and Anssi Laaksonen. "Instrumentation and FE Analysis of a Large-Span Culvert Built under a Railway, in Finland." Structural Engineering International 26, no. 4 (November 2016): 357–64. http://dx.doi.org/10.2749/101686616x14555429843807.

Full text

APA, Harvard, Vancouver, ISO, and other styles

38

He, Fang Ding, Jin Ping Cui, Jun Sui, and Yi Fan Yu. "Analysis of Differential Settlement Influence on Internal Force of Box Culvert Structure." Applied Mechanics and Materials 353-356 (August 2013): 225–28. http://dx.doi.org/10.4028/www.scientific.net/amm.353-356.225.

Full text

Abstract:

The foundation settlement of soft soil highway engineering is too large, resulting in pavement wave-like because of differential settlement between the structure and adjacent soft soil foundation, which seriously impacts on traffic safety. Considering the soft soil foundation in the foundation treatment methods of CFG pile, sand bag well, powder spraying pile, we analyze differential settlement on the degree of influence structure internal force distribution, then provide the reference for the design and calculation.

APA, Harvard, Vancouver, ISO, and other styles

39

Adil Jasim, Nidaa, and . "Design of Box Culvert in Iraqi Highways Considering Catchment Areas." International Journal of Engineering & Technology 7, no. 4.37 (December 13, 2018): 157. http://dx.doi.org/10.14419/ijet.v7i4.37.24093.

Full text

Abstract:

In Iraq, the infrastructures are developing rapidly, so it is necessary to consider the hydrology of the developed catchment before constructing any drainage facilities such as culvert to prevent traffic disruption during rain. In this study, sizing of box culvert for highways in Iraq is proposed using rational method for determination of peak runoff from small catchment (less than 3 km2). Rainfall depth was used to derive the intensity duration frequency curve, and then the rainfall intensity was found. However, soil conservation service curve number (SCS-CN) was used in the estimation of peak runoff from catchment with size ranging from 3 to less than 30 km2 using the soil classification and the curve number. HY-8 computer software was used for sizing square and circular sections. Circular sections were also calculated. The appropriate sizes for square sections in large basins are 3 m to 4 m and 2 m to 2.9 m for more than 114 m3/s and 32 m3/s respectively, but for circular sections, diameters were 4.1m, from 3 m to 3.8 m and from 2.5 m to 2.9 m under flow rates more than 160 m3/s, 68 m3/s and 25 m3/s respectively. However, for small basins, square sections sizes were 3m to 3.1m and 2 m to 2.7 m for flow rates more than 23 m3/s and 8 m3/s respectively. Diameters for circular sections were 3 m to 3.2 m and 2 m to 2.9 m under flow rates 23 m3/ s and 8 m3/s respectively.

APA, Harvard, Vancouver, ISO, and other styles

40

Sargand, Shad, Teruhisa Masada, and Andrew Moreland. "Measured Field Performance and Computer Analysis of Large-Diameter Multiplate Steel Pipe Culvert Installed in Ohio." Journal of Performance of Constructed Facilities 22, no. 6 (December 2008): 391–97. http://dx.doi.org/10.1061/(asce)0887-3828(2008)22:6(391).

Full text

APA, Harvard, Vancouver, ISO, and other styles

41

Cheng, Chihao, Shaoming Liao, Lisheng Chen, and Junzuo He. "Jacking precision control of pipe roof and large box culvert below urban expressway-a case study of a large underpass in Shanghai." IOP Conference Series: Earth and Environmental Science 703, no. 1 (March 1, 2021): 012050. http://dx.doi.org/10.1088/1755-1315/703/1/012050.

Full text

APA, Harvard, Vancouver, ISO, and other styles

42

Ramadan, Safwat H., and M. Hesham El Naggar. "Effect of large-span three-sided culvert configuration on its performance at service and ultimate loading conditions." Tunnelling and Underground Space Technology 122 (April 2022): 104346. http://dx.doi.org/10.1016/j.tust.2021.104346.

Full text

APA, Harvard, Vancouver, ISO, and other styles

43

Jakob, M., D. Anderson, T. Fuller, O. Hungr, and D. Ayotte. "An unusually large debris flow at Hummingbird Creek, Mara Lake, British Columbia." Canadian Geotechnical Journal 37, no. 5 (October 1, 2000): 1109–25. http://dx.doi.org/10.1139/t00-013.

Full text

Abstract:

On 11 July 1997 a very large debris flow occurred at Hummingbird Creek, Mara Lake, British Columbia. Long-term antecedent precipitation was record breaking, whereas short-term precipitation at Salmon Arm did not exceed the 2 year return period for intensity. A 25 000 m3 debris avalanche was initiated downstream of a forest road culvert, which drained a small catchment that had been artificially increased by a factor of three. The debris avalanche entered the channel of Hummingbird Creek and triggered a debris flow. Velocities were back-calculated using the forced vortex equation and multiplied by the cross-sectional area to obtain peak discharge estimates that ranged from 600 to 1000 m3/s. Approximately 92 000 m3 of sediment was deposited during this event, which makes it the largest nonvolcanic debris flow recorded in British Columbia to date. A three-dimensional runout model was used to simulate this event. Results are in fair agreement with the observed behaviour. This study emphasizes the need to carefully manage forest resources with high downstream risks and the need for hazard assessments prior to development on alluvial fans.Key words: debris avalanche, debris flow, DAN model, hydroclimatic, peak discharge, British Columbia.

APA, Harvard, Vancouver, ISO, and other styles

44

Christian, Andrew, and Heri Prasetya. "CULVERT DESIGN ANALYSIS USING HY-8 SOFTWARE TO DRAIN SURFACE RUNOFF DISCHARGE AT CV GUNUNG BATUJAJAR, WEST BANDUNG REGENCY, WEST JAVA, INDONESIA." Jurnal Inovasi Pertambangan dan Lingkungan 2, no. 1 (July 29, 2022): 20–31. http://dx.doi.org/10.15408/jipl.v2i1.25829.

Full text

Abstract:

CV Gunung Batujajar is a company engaged in the mining of industrial minerals in the form of andesite that applies an open-pit mining system (surface mining). Regarding the mining drainage system that is applied, there are still obstacles in dealing with drainage problems. The flow of rainwater in CV Gunung Batujajar generally flows in two places, to the large opening pit in the south with a percentage of 70% water flow and to the north by 30%. After further review, 30% of the water flow turned out to be flowing towards residents' housing and causing the water to overflow until it was flooded, thus disrupting the productivity of the population. Therefore, the authors conducted research related to the analysis of the drainage system using a culvert. In conducting the research, the authors took several types of data such as rainfall data for 10 years, field data on road geometry conditions, etc. With a planned rainfall value of 157.06 mm/day and a planned rainfall intensity of 54.45 mm/hour obtained the design runoff discharge is 0.35 m3/s. For the culvert design at the first outlet, a trapezoidal shape design is used with a base length of 0.225 m and a height of 0.2 m. As for the design at the second outlet, it is in the form of a trapezoid with a base length of 1.2 m and a height of 1.3 m. The second outlet is concluded to be more technically secure.

APA, Harvard, Vancouver, ISO, and other styles

45

Zhi, Chun Hong. "Economic Analysis of Buried Corrugated Steel Culverts Considering Deterioration." Advanced Materials Research 960-961 (June 2014): 281–86. http://dx.doi.org/10.4028/www.scientific.net/amr.960-961.281.

Full text

Abstract:

The characteristics of the corrugated steel culvert and the deterioration of the structure are analyzed. The Life Cycle Cost (LCC) approach is put forward to analysis the initial, maintenance and recycling cost of the different material culverts. The user delay costs are added to the typical LCC values considering the deterioration and the failure of structures. The analysis and the economic comparison results show that the total LCC values at the failure emergency situation is much larger than the situation when the deterioration is considered initiatively. Such economic analysis can help the project decision makers better understand the risks associated with deterioration and failure. The inspection and maintenance schedule should be formulated considering the culvert size, the environment in which the culvert is placed, and the characteristics of the soil and the backfill.

APA, Harvard, Vancouver, ISO, and other styles

46

Erkinaro, J., H. Erkinaro, and E. Niemelä. "Road culvert restoration expands the habitat connectivity and production area of juvenile Atlantic salmon in a large subarctic river system." Fisheries Management and Ecology 24, no. 1 (January 20, 2017): 73–81. http://dx.doi.org/10.1111/fme.12203.

Full text

APA, Harvard, Vancouver, ISO, and other styles

47

Келехсаев, Дмитрий, and Dmitry Kelekhsaev. "CALCULATION OF THE RAPID FLOW OF WATER AT THE OUTLET OF THE ROUND PIPE IN THE DOWNSTREAM OF THE CULVERTS." Construction and Architecture 6, no. 3 (September 25, 2018): 29–34. http://dx.doi.org/10.29039/article_5bee8ada6e3492.04272155.

Full text

Abstract:

The article proposes a mathematical modeling of the rapid flow spreading in the wide downstream of the culvert depending on the flow rate, the relative expansion of the downstream and the depth of the water at the outlet of the round pipe. An open water flow is considered in a non-pressure spreading mode. When the Froude numbers are large than four in the channel with a relative expansion of b = 3–7, pairing is established according to the type of free flow of a two-dimensional turbulent flow, the depths and flow rates at each point, the geometry of the free flow zone are determined. The flow parameters are calculated at any point of the free flow area using the Maple software package. The adequacy of the model extreme current line with the experimental one is shown.

APA, Harvard, Vancouver, ISO, and other styles

48

Maniecki, Łukasz. "Numerical Modelling of Fish Passage with Turning Pools." Archives of Hydro-Engineering and Environmental Mechanics 65, no. 1 (June 1, 2018): 41–65. http://dx.doi.org/10.1515/heem-2018-0004.

Full text

Abstract:

AbstractAn assessment of operating conditions in a baffled fish passage with pool dimensions of 2.2 × 3.0 m, and 180° horizontally turning pools, was carried out using numerical computations and a site survey of water flow velocity distribution. Velocity was measured with a PMS electromagnetic flowmeter and a hydrometric current meter in representative cross-sections of the fish passage in the pool centres and in the baffle barrier cross-section area. Numerical computations were also performed for two alternative baffle locations in the fishway. One reflected the actual conditions, and the other was an alternative arrangement designed to improve hydraulic conditions for fish migration. The numerical model used the Large Eddy Simulation (LES) method, which makes it possible to detect large vortexes. The study pays close attention to the velocity field analysis as well as the distribution and sizes of vortexes in the turning pool of the culvert. The results of numerical computations and the site survey show high consistency, and the proposed baffle placement modification significantly improves flow conditions, especially in the entry section of the passage.

APA, Harvard, Vancouver, ISO, and other styles

49

Bakht, Baidar, and Akhilesh C. Agarwal. "On distress in pipe-arches." Canadian Journal of Civil Engineering 15, no. 4 (August 1, 1988): 589–95. http://dx.doi.org/10.1139/l88-079.

Full text

Abstract:

Cracking of bolt holes is a very common form of distress in pipe-arch type of soil–steel structures, the conduit walls of which are subjected to very large radial soil pressures in their lower haunches. This paper, in discussing the mechanics of this form of distress, concludes that the cracks are formed mainly due to the inability of the soil in the haunch areas to sustain the very high pressures. It also contains methods to alleviate these problems, both at the design and at the construction stage. Guidelines for proper bolt arrangements are given, and use of low-strength concrete around and under the haunches is recommended. Pouring of concrete in segments is suggested to avoid potential flotation of the pipe during construction. A case history incorporating this measure is given to demonstrate its feasibility. Key words: soil–steel structure, pipe-arch, culvert, highway bridges, bolt-hole tears.

APA, Harvard, Vancouver, ISO, and other styles

50

Neeson, Thomas M., Michael C. Ferris, Matthew W. Diebel, Patrick J. Doran, Jesse R. O’Hanley, and Peter B. McIntyre. "Enhancing ecosystem restoration efficiency through spatial and temporal coordination." Proceedings of the National Academy of Sciences 112, no. 19 (April 27, 2015): 6236–41. http://dx.doi.org/10.1073/pnas.1423812112.

Full text

Abstract:

In many large ecosystems, conservation projects are selected by a diverse set of actors operating independently at spatial scales ranging from local to international. Although small-scale decision making can leverage local expert knowledge, it also may be an inefficient means of achieving large-scale objectives if piecemeal efforts are poorly coordinated. Here, we assess the value of coordinating efforts in both space and time to maximize the restoration of aquatic ecosystem connectivity. Habitat fragmentation is a leading driver of declining biodiversity and ecosystem services in rivers worldwide, and we simultaneously evaluate optimal barrier removal strategies for 661 tributary rivers of the Laurentian Great Lakes, which are fragmented by at least 6,692 dams and 232,068 road crossings. We find that coordinating barrier removals across the entire basin is nine times more efficient at reconnecting fish to headwater breeding grounds than optimizing independently for each watershed. Similarly, a one-time pulse of restoration investment is up to 10 times more efficient than annual allocations totaling the same amount. Despite widespread emphasis on dams as key barriers in river networks, improving road culvert passability is also essential for efficiently restoring connectivity to the Great Lakes. Our results highlight the dramatic economic and ecological advantages of coordinating efforts in both space and time during restoration of large ecosystems.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Large culvert'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles