Evaluation of the local scour downstream  untraditional bridge piers

H. Hussein, Hamid; A. K. Juma, Inam; I. Hammo, Nashwan

	Evaluation of the local scour downstream untraditional bridge piers
Journal of Engineering and Sustainable Development
Article 1, Volume 16, Issue 3, 2012, Pages 36-49
Authors
Hamid H. Hussein; Inam A. K. Juma; Nashwan I. Hammo
Abstract
The reduction of local scour downstream bridge piers got a massive concentration by several studies. In this study the D/S edge of the rectangular section semicircular bridge pier was reduced. This reduction was built to determine its influence on the local scour D/S these piers. Four models of the piers were manufactured from thermo-stone. The upstream semicircle diameter was fixed by a 10 cm, while the D/S diameter was changed to 4,6,8 and 10 cm . The experimental results provide evidence that the reduce of the D/S diameter of the pier leads to decrease the D/S scour depth and length . Moreover, in its place the sand was noticeably deposited D/S the pier. The experimental results was used to develop two liner empirical relations the first to estimate the ratio of maximum scour depth to U/S diameter of the pier ds/d1 . While the second to estimate the ratio of the length of scour to U/S diameter of the pier X/d1 , in terms of the ratio for D/S diameter of the pier to U/S diameter of the pier d2/d1 , length of the scour U/S the pier to D/S diameter Z1/d2, maximum width of scour to D/S diameter Z2/d2 , maximum height of sand deposition D/S of the pier to D/S diameter y/d2 and Froude number Fr. Furthermore, the two empirical relations were compared with the results of the artificial neural network (ANN). The utilize of ANN techniques yields superior results for predicting the maximum depth and length of scour D/S these piers
Keywords
Hydraulic Structures; Bridge Piers; local scour; ANN

Statistics Article View: 190 PDF Download: 156