Experimental Investigation of the Effect of Slot Pier Opening Area on Local Scouring of Bridge Pier

Document Type : Research Paper

Authors

1 Graduate Master of Science of Civil Engineering- Hydraulic Structure, Khorramshahr University of Marine Science and Technology, Iran

2 Assist. Prof., Dept. of Marine Structure Engineering, Khorramshahr University of Marine Science and Technology, Iran

3 Assoc. prof., Dept. of Soil Watershed Protection- Tehran, Iran

4 Prof. of Water Science Department, Shahid Chamran University of Ahvaz, Iran

Abstract

   The construction of bridges within the river beds often makes changes to the shape and direction of the rivers. These changes take the natural actions of the river, that one of them is the local scouring around the bridges' piers and can cause annually damage. Therefore, many researches have been carried out to control and reduce the scouring. One of the methods presented by researchers is using slot at piers.  In present study, the effect of Pier Opening Area on local scouring around the pier with rectangular section is experimentally investigated. For this purpose, piers with square shape slots and different dimensions were used. The piers were tested at three levels (near the water level, on the bed and under the bed) and four Froude numbers.  The result showed that the maximum scouring depth and the volume of hole scour had a direct relationship with slot level relative to bed and Froude number and an inverse relationship with Pier Opening Area. The best performance belonged to the slot with greater dimensions which was located under the bed level in the minimum Froude number condition that reduced the depth of scouring about 55.4 percent.  

Keywords


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