Effects of collars on local scour around semi-circularend bridge abutments

Download

index.pdf

Date

2011

Author

Daşkın, Süeyla

Metadata

Show full item record

Item Usage Stats

247
views

182
downloads

During severe floods, bed material around bridge piers and abutments are scoured by the flow and as a result, bridges are subject to damages. These damages are mostly unrepairable and can result in loss of lives and property. In this thesis study, abutment scour under clear-water condition was investigated and collars were tested as scour countermeasures around the abutments. The experimental study was carried out in a rectangular channel with an almost uniform cohesionless bed material of d50=1.50 mm for a test period of 3-hours. The channel was 28.5 m long and 1.5 m wide. The erodible bed material was placed into the test section that was 5.8 m long and 0.48 m deep. For this thesis study, 60 experiments were carried out with and without various collars placed at different elevations around the abutments. The scour formation around the abutments with collars was observed and scour reduction efficiencies of the collars were studied. Experiment results were compared with the previous studies of Doğan (2008) and Kayatürk (2005) in terms of sediment size, abutment shape and flow depth, and the effects of these factors on collar's scour reduction efficiency were studied. Based on the results of the experimental studies, it was observed that scour depths decreased as the collar width increased and the collar placed deeper into the sediment bed for a given abutment length. When the present study and the previous studies were compared, it was observed that sediment size and flow depth had no significant effect on the scour reduction performances of the collars.

Subject Keywords

Bridge failures.

URI

http://etd.lib.metu.edu.tr/upload/12613310/index.pdf
https://hdl.handle.net/11511/20529

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Effects of collars on scour reduction at bridge abutments Doğan, Abdullah Ercüment; Göğüş, Mustafa; Department of Civil Engineering (2008) Bridge failures are generally resulted from scour of the bed material around bridge piers and abutments during severe floods. In this study, scour phenomenon around bridge abutments and collars, located at abutments as scour countermeasures, were experimentally studied. The experimental study was carried out under clear-water scour conditions with uniform non-cohesive sediment (having a grain size diameter of d50=0.90 mm). The experimental flume is a rectangular channel of 30 m long and 1.5 m wide filled wi...
Evaluation of scouring reliability at bridge abutments Yanmaz, Ali Melih (2012-04-26) Serious scouring may take place around bridge abutments during floods, which can lead to considerable damage or structural collapse. Design of abutment footings must, therefore, rely on the estimation of maximum possible depth of scour through the bridge opening. Deterministic scour-prediction equations are based on simplified assumptions and they do not account for randomness of the scouring variables, which leads to an unavoidable risk in footing design. This study is concerned with the development of a n...
Scour and scour protection at bridge abutments Kayatürk, Şerife Yurdagül; Göğüş, Mustafa; Department of Civil Engineering (2005) Bridge failures are mainly caused by scouring the bed material around bridge foundations during flood. In this study, scour phenomenon around bridge abutments is experimentally studied. Effect of abutment size, location and size of the collars placed around the abutments, time evaluation of scour hole around the abutment, scour characteristics of abutment and pier interaction were experimentally investigated. Scour measurements were conducted in a rectangular channel of 30 m long and 1.5 m wide filled with ...
Development of a safetyinspection methodology for river bridges Berk, Aysu; Yanmaz, Ali Melih; Department of Civil Engineering (2006) River bridges get damaged or even collapse because of various reasons, such as development of adverse hydraulic conditions during severe floods, disastrous earthquakes, deficiencies in structural and geotechnical design, material deficiencies, or other unexpected external factors. Failure of service at vital lifelines, bridges, can lead to loss of several lives and properties, traffic disruption, and/or deficiencies in daily usage. Existing structures should be monitored periodically for decision-making and...
Effects of inclination of bridge piers on scouring depth Bozkuş, Zafer (2004-08-01) For a safe design of a bridge pier footing, it is important to estimate the maximum depth of scour as accurately as possible. The aim of this experimental study is to investigate the effects of inclination of bridge piers on local scour depths around bridge piers. Single circular piers inclined toward the downstream direction were founded in a uniform bed material. Near threshold conditions were employed. The results of this study indicate that the local scour depth decreases as the inclination of the pier ...

Citation Formats

S. Daşkın, “Effects of collars on local scour around semi-circularend bridge abutments,” M.S. - Master of Science, Middle East Technical University, 2011.