Effects of increasing the width of collar on reduction of scouring surrounding the rectangular piers in a 180-degree bend
Abstract Employment of protective structures is vital for reducing the effect of the local scour created surrounding the bridge piers. One of the most effective protective structures used for controlling and reducing scour surrounding the bridge piers is the collars. Hence, research on the mechanism...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
| Published: |
SpringerOpen
2023-02-01
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| Series: | Applied Water Science |
| Subjects: | |
| Online Access: | https://doi.org/10.1007/s13201-023-01884-8 |
| _version_ | 1797863860612366336 |
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| author | Danesh Dehghan Mohammad Vaghefi Masoud Ghodsian |
| author_facet | Danesh Dehghan Mohammad Vaghefi Masoud Ghodsian |
| author_sort | Danesh Dehghan |
| collection | DOAJ |
| description | Abstract Employment of protective structures is vital for reducing the effect of the local scour created surrounding the bridge piers. One of the most effective protective structures used for controlling and reducing scour surrounding the bridge piers is the collars. Hence, research on the mechanism of scouring surrounding the combination of pier and collar as well as the effect of collar on reduction of scouring surrounding the pier is of great significance. In this study, the effect of various collar width-to-pier width ratios on reduction of scouring parameters surrounding the rectangular piers has been investigated experimentally in various 180-degree sharp bend positions. The experiments were conducted under clear water and threshold of sediment motion in the upstream straight path. Results indicated that collars with collar width-to-pier width ratios equal to 3 to 4 perform the best at reducing the maximum depth of scouring in front of the nose of piers. Increasing the width of collar surrounding the piers reduces the maximum depth of scouring. Increasing the length of pier reduces the efficiency and effectiveness of the collar in delaying the scour process at the pier nose as well as the amount of the maximum scour reduction. The highest amount of scour depth reduction occurred in the vicinity of the pier and the collar at the 90-degree section with the collar installed with a ratio of collar width to pier width equal to 4 surrounding the piers with a ratio of length to width equal to 2 and 3 by approximately 75 and 70%, respectively. |
| first_indexed | 2024-04-09T22:43:36Z |
| format | Article |
| id | doaj.art-374c3505dc6e462fa572020f0dcb901c |
| institution | Directory Open Access Journal |
| issn | 2190-5487 2190-5495 |
| language | English |
| last_indexed | 2024-04-09T22:43:36Z |
| publishDate | 2023-02-01 |
| publisher | SpringerOpen |
| record_format | Article |
| series | Applied Water Science |
| spelling | doaj.art-374c3505dc6e462fa572020f0dcb901c2023-03-22T12:01:29ZengSpringerOpenApplied Water Science2190-54872190-54952023-02-0113311710.1007/s13201-023-01884-8Effects of increasing the width of collar on reduction of scouring surrounding the rectangular piers in a 180-degree bendDanesh Dehghan0Mohammad Vaghefi1Masoud Ghodsian2Department of Civil Engineering, Faculty of Engineering, Persian Gulf UniversityDepartment of Civil Engineering, Faculty of Engineering, Persian Gulf UniversityFaculty of Civil and Environmental Engineering, Tarbiat Modares UniversityAbstract Employment of protective structures is vital for reducing the effect of the local scour created surrounding the bridge piers. One of the most effective protective structures used for controlling and reducing scour surrounding the bridge piers is the collars. Hence, research on the mechanism of scouring surrounding the combination of pier and collar as well as the effect of collar on reduction of scouring surrounding the pier is of great significance. In this study, the effect of various collar width-to-pier width ratios on reduction of scouring parameters surrounding the rectangular piers has been investigated experimentally in various 180-degree sharp bend positions. The experiments were conducted under clear water and threshold of sediment motion in the upstream straight path. Results indicated that collars with collar width-to-pier width ratios equal to 3 to 4 perform the best at reducing the maximum depth of scouring in front of the nose of piers. Increasing the width of collar surrounding the piers reduces the maximum depth of scouring. Increasing the length of pier reduces the efficiency and effectiveness of the collar in delaying the scour process at the pier nose as well as the amount of the maximum scour reduction. The highest amount of scour depth reduction occurred in the vicinity of the pier and the collar at the 90-degree section with the collar installed with a ratio of collar width to pier width equal to 4 surrounding the piers with a ratio of length to width equal to 2 and 3 by approximately 75 and 70%, respectively.https://doi.org/10.1007/s13201-023-01884-8Rectangular pierCollarCollar width-to-pier width ratioScour reductionRatio of pier length to width180-degree bend |
| spellingShingle | Danesh Dehghan Mohammad Vaghefi Masoud Ghodsian Effects of increasing the width of collar on reduction of scouring surrounding the rectangular piers in a 180-degree bend Applied Water Science Rectangular pier Collar Collar width-to-pier width ratio Scour reduction Ratio of pier length to width 180-degree bend |
| title | Effects of increasing the width of collar on reduction of scouring surrounding the rectangular piers in a 180-degree bend |
| title_full | Effects of increasing the width of collar on reduction of scouring surrounding the rectangular piers in a 180-degree bend |
| title_fullStr | Effects of increasing the width of collar on reduction of scouring surrounding the rectangular piers in a 180-degree bend |
| title_full_unstemmed | Effects of increasing the width of collar on reduction of scouring surrounding the rectangular piers in a 180-degree bend |
| title_short | Effects of increasing the width of collar on reduction of scouring surrounding the rectangular piers in a 180-degree bend |
| title_sort | effects of increasing the width of collar on reduction of scouring surrounding the rectangular piers in a 180 degree bend |
| topic | Rectangular pier Collar Collar width-to-pier width ratio Scour reduction Ratio of pier length to width 180-degree bend |
| url | https://doi.org/10.1007/s13201-023-01884-8 |
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