TY  - JOUR
AU  - Mohammadi, Mirali 
PY  - 2008
TI  - Boundary Shear Stress around Bridge Piers
JF  - American Journal of Applied Sciences
VL  - 5
IS  - 11
DO  - 10.3844/ajassp.2008.1547.1551
UR  - https://thescipub.com/abstract/ajassp.2008.1547.1551
AB  - This research presents the measurement of boundary shear stress around the base of some elliptical shaped bridge piers using Preston tube technique. The uniform flow was established and a series of measurements having different discharges and channel bed slopes were undertaken. General results are established and then the effects of flow separation on the hydraulic theory are assessed. The Analysis of results shows that behind the bridge piers (horseshoe area); the amount of boundary shear stress   reduces   dramatically.  The  figure  for the rate of boundary shear stress of nose to end is about τr = τn/τe = 3.6. It has a remarkable reduction even in steep slopes. The bed shear stress was found to intensify near the nose of the piers. The distribution of boundary shear stress in both mild and steep channel bed slopes along spanwise direction is presented that may give a valuable perspective of the flow action around piers.