HUA LI. Countermeasures against Scour at Bridge Abutments (Under the direction of Dr. BRIAN D. BARKDOLL) Scour at bridge abutments can cause damage or failure of bridges and result in excessive repairs, loss of accessibility, or even death. To mitigate abutment scour, both clear-water and live-bed laboratory experiments in a compound channel were performed using parallel walls and spur dikes as...

Taiwan is located in the rim of the Pacific Ocean. The activities of the earthquake happen frequently, which threaten the safety of the bridge in the Taiwan Island. Besides, the severe floods resulted from the typhoon or storm events can cause great damages due to the bridge scouring. The steep-sloped rivers and sand mining problems in Taiwan accelerate the degradation of the riverbed. Scouring...

Scouring around a bridge pier is a complex phenomenon. More laboratory experiments are required to understand the scour mechanism. This paper focused on time development of local scour around piers and piles in semi integral bridges. Laboratory data collected at Hydraulics Laboratory, University of Malaya was analyzed for this purpose. Tests were performed with two different uniform sediment si...

Many of the huge structures like New Esna, and New Nega Hammadi Barrages face a great harmful caused by local scour downstream (DS) their stilling basins. It is planned to redesign many of these structures to minimize these harmful impacts of the DS local scour. This research paper presents the results of an extensive experimental investigation on using an optimized submerged curved deflector t...

The process of local scour around bridge piers is fundamentally complex due to the three-dimensional flow patterns interacting with bed materials. For geotechnical and economical reasons, multiple pile bridge piers have become more and more popular in bridge design. Although many studies have been carried out to develop relationships for the maximum scour depth at pile groups under clear-water ...

-We measured scour of the redds of chinook salmon Oncorhynchus tshawytscha on dredge tailings and natural substrates in three tributaries of the Klamath River, California. We measured maximum scour with scour chains and net scour by surveying before and after high winter flows. Scour of chinook salmon redds located on dredge tailings exceeded scour of redds on natural substrates, although the d...

Received: February 02, 2017 Revised: March 13, 2017 Accepted: May 19, 2017 Abstract: Introduction: Bridge scour is one of the major causes of bridge failure. Prediction of the maximum depth and shape of local scour plays an important role in bridge design and maintenance. In this paper, k-ε turbulent model combined with wall function was employed and complex flow fields are exhibited. The bed l...

Laboratory tests were carried out to assess the local scour by three-dimensional wall jets from a square crosssection nozzle. To this end, three different tailwater depths were used and the jet expansion ratio was held greater than ten. Velocity measurements were conducted using a one component laser Doppler anemometer. The jet exit Reynolds number was maintained to 1x10 and this value can be c...

Many permanent spillway tunnels of high earth-rock dams are rebuilt from their diversion tunnels. Scour problem is focused because of their high water head and velocity. Energy Approach is a new method to Estimating Scour and is used here to estimate the depth of scour downstream of 1 spillway tunnel of Zipingpu Project. The method is illustrated working fine by comparing its results with data ...