It is still a blank to study the influence of water flow angles upon local scouring around pile groups for large or
ultra-large pile groups. Through testing in a large-scale flume, the influence of water flow angles upon local scouring around a
quincunx pile group was studied，and the shape of scouring in different flow angles and the resultant enlarging coefficients of
included angles in pile groups were obtained，provide references for engineering design and revision of provisions on local
scouring in specifications and standards.