In order to explore the abrasion damage to bridge pier under erosion of flow in mountain area

field investigation and CFD numerical analysis were adopted.Pier abrasion of 13 bridges crossing the upstream of Minjiang River were surveyed

the depth and shapes of abrasion were measured

the hardness of concrete was also measured.According to the measured data

we modified the finnie erosion wear model on the basis of the assumption that the critical speed has a linear correlation with the elastic modulus.And two phase flow model was constructed.A group of parameters

including shape and size of piers

water depth

flow velocity

sandy ra

tes and grading were taken into account to study their effects on the depth and area of abrasion.The results show that the strongest abrasion resistance is circular pier and the abrasion damage degree of the bridge pier has a basic linear relationship with the sandy rates

but the influence of the water depth is negligible.The flow velocity has a significant effect on the maximum erosion thick

but has negligible effect on the average erosion thickness.With the same sediment concentration

the larger particle size

the greater abrasive action of the bridge pier will be.Average erosion thickness of concrete pier can be predicted according to 3

5

mm per year.