When depth of flow past a river bridge exceeds opening under the bridge, the flow under the bridge becomes pressurized. The water is directed downward and under the bridge deck, causing increase in velocity and shear stress on the bed thereby increasing bed scour. This is termed as Pressure Flow Scour. The present study investigates the phenomenon of pressure flow scour resulting from a submerg...

In this study, a new procedure to determine the optimum dimensions for a rectangular collar to minimize the temporal trend of scouring around a pier model is proposed. Unlike previous methods of predicting collar dimensions around a bridge pier, the proposed approach concerns the selection of different collar dimension sizes around a bridge scour in terms of the flume's upstream (Luc/D), downst...

River bridge piers may collapse due to the local scour around their foundations. It is known that an effect of three-dimensional flow field develops near pier and geometric complexity a non-cylindrical may, correspondingly, increase process. also various devices be used as countermeasures. This manuscript explores use bed sill countermeasure for at complex compound array piles, pile cap, two in...

The evolution of bridge pier scour is very important for bridge safety warning and assessment. During typhoon seasons in Taiwan, the torrential river flow often causes scour monitoring instruments to fail in their attempt to measure the temporal variations of pier scour depths. To better understand the scouring phenomenon during a large flood event, this study proposes a fast and reliable metho...

The most important causes of bridge failure are local scour. In this study, laboratory experiments were conducted to investigate the effectiveness of slot as a protection device in reduction of depth of scour at cylindrical piers under clear water flow conditions. The development time of scour depth at the circular pier with and without a slot as a protection device was conducted. The experimen...

Bridges are often built in locations susceptible to multiple extreme hazards. Meeting some or all of these constraints drives the development of innovative multi-hazard design concepts. This paper presents the results of research conducted to develop and experimentally validate such multi-hazard bridge pier concepts. The first concept is a pier-bent made of concrete filled steel tube columns. F...

In many cases, a set of obstacles, such as bridge piers and abutments, are located in the river waterway. Bridge piers disrupt river’s normal flow, and the created turbulence and disturbance causes diversion of flow lines and creates rotational flow. Geometric shape and position of the piers with respect to flow direction and also number of piers and their spacing are effective on changing the ...

This study is devoted towards evaluating seismic performance of a three-span continuous highway bridge subjected to moderate to strong earthquake ground motions in its longitudinal direction. In this regard, nonlinear dynamic analysis of the bridge based on the direct time integration approach using the 4 order Runge-Kutta method is conducted. Two types of isolation bearings are used in the ana...

Original scientific paper The objectives of this paper are to perform a comparative analysis of the large-scale system of a high-pier railway bridge subjected to stationary and nonstationary spatially varying earthquake excitations using the pseudo-excitation method (PEM), and to estimate whether or not the non-stationary stochastic analysis of the high-pier railway bridges under tri-directiona...