In order to successfully demolish a high pier reinforced concrete aqueduct by blasting between the 75#~84# piers of Dongfeng Canal in Yichang City and reduce the impact on the surrounding complex environment,a bidirectional collapse design was adopted.In the design scheme,the aqueducts between the 75#~76# piers collapse in a northerly direction perpendicular to the aqueduct trend,and the aqueducts 77#~84# piers collapse westward along the aqueduct trend.More precisely,an initiation network of electronic and non-electric detonators with delays of 50 ms and 150 ms was adopted using the 75# pier as the initiation point.Moreover,the harmful effects of blasting on the environment were controlled by using lifting holes as blast holes,excavating vibration reduction ditches,hanging nets and covering protection layer,storing water in the trench body,and covering soil protection.The results show that the aqueduct collapsed with a 4-minute delay after initiation,and the collapsed pier body was basically decomposed into blocks with intact aqueduct body,with most fragments scattered along the trend within 10 m of the central axis of the aqueduct,and only a few small pieces flying farther than 10 m.The adopted protective measures can effectively control the blasting flying rocks and vibration,and no damage has been found to the inverted siphon of temporary water delivery pipeline and the road pavement.The project was carried out successfully despite the delay in collapse.The possible reasons for the delayed collapse include no incision on outside of the structural column ,the delay time interval between pier columns is small,and the blasting incision is small.