Experimental study: scour interference between vertical-wall abutment and two shape of bridge piers

Abstract

Abstract Local scour considered as one of the main hazard factors that damaging bridges and in order to understand and controlling this problem, numerous researchers investigated its impact around pier or abutment in isolation but few take into account the consequences of pier proximity to abutment. This study aims to show the effect of pier-abutment scour interference. Under clear-water conditions, laboratory experiments were conducted utilizing vertical-wall abutment and two shape of pier (rectangular and ogival) at three different spacing (23.75, 16 and 9cm), and the influence of other parameters on reducing scouring process were also investigated. Approximately all results showed the increasing in pier scour depth with decreasing in abutment scour depth when reducing the spacing between them, where the maximum pier readings of scour depth was recorded at the smallest spacing. Also, scour increased with increasing flow intensity, Froude number and decreasing flow depth. Moreover, the maximum scour depth caused by rectangular shape was more than ogival shape by percentage about 11%.