円柱橋脚の局所洗掘深さの予測 : 第1報,静的洗掘における水深/円柱直径≦1.2の場合

概要

論文の詳細を見る
Previous experimental data concering to the terminal scour depth by clear-water scour around a circular bridge pier are examined thoroughly. The effects of the pier size D, the flow velocity U, the water depth h_o and the sand grain size d_s on the terminal scour depth are investigated. For the case of h_o/D≦1.2, which is a considerable effect on the scour, the main results obtained are as follows. The terminal scour depth Z_s/D is represented by a function of three dimensionless factors, the sediment number N_s=U/[(σ/p-1)gd_s]^<0.5>, the water depth h_o/D and the sediment Reynolds number Re_d=Ud_s/ν, where σ/p is the ratio of solid density to fluid density, and is formulated as Z_s/D=0.09N_s^<0.24>(h_o/D)^<0.60>Re_d^<0.12>. This equation agrees well with the former experimental data within ±7 %.
1995-12-25