The effect of thickness of pillar in the channel bend to changes the coefficient of superelevation

The present study discusses phenomena occurred in a natural channel where a bridge is built in a river bend. the present study aims at determining the effect of pillars thickness on water surface slope in transverse direction on channel bend which is defined in superelevation coefficient (cs). physical modelling applies 180o channel bend,0.75 m radius,and 0.5 m width. it was applied in both with pillar and without pillar flows in subcritical-turbulent flow. for the flows with pillar there were pillar interval of 30o and 60o. the results show that the highest value of cs (7.826) is found in the flows with pillar of the 30o interval in 30o river bend. in the interval of 60o where the pillar thickness is 3 cm,the cs value is greater than when the pillar thickness is 2 cm,on the other hand in the interval of 30o the cs value is smaller. it is recommended for the next research to apply hydraulic condition with average velocity divided by the critical velocity must be greater than one. © school of engineering,taylor’s university.