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天然河道糙率表,,,,,,,,,,,,,,,

河槽類型及情況,,,,,,,,,最小值,,正常值,,,最大值,

第一類小河(汛期最大水面寬度30m),,,,,,,,,,,,,,,

1、平原河流,,,,,,,,,,,,,,,

(1)清潔,順直,無沙灘,無潭,,,,,,,,,0.025,,0.030,,,0.033,

(2)清潔,順直,無沙灘,無潭,但多石多草,,,,,,,,,0.030,,0.035,,,0.040,

(3)清潔,彎曲,稍許淤灘和潭坑,,,,,,,,,0.033,,0.040,,,0.045,

(4)清潔,彎曲,稍許淤灘和潭坑,但有草石,,,,,,,,,0.035,,0.045,,,0.050,

"(5)清潔,彎曲,稍許淤灘和潭坑,有草石,但水深較淺,河堤坡度多變,平面上回流區較多",,,,,,,,,0.040,,0.045,,,0.050,

(6)清潔,彎曲,稍許:淤灘和潭坑,但有草石并多石,,,,,,,,,0.045,,0.050,,,0.060,

(7)多滯流間段,多草,有深潭,,,,,,,,,0.050,,0.070,,,0.080,

(8)多叢草河段,多深潭,或草木灘地上的過洪,,,,,,,,,0.075,,0.100,,,0.015,

2.山區河流(河槽無草樹,河岸較陡,岸坡樹叢過洪時淹沒),,,,,,,,,,,,,,,

(1)河底:礫石,卵石間有孤石,,,,,,,,,0.030,,0.040,,,0.050,

(2)河底:卵石和大孤石,,,,,,,,,0.040,,0.050,,,0.070,

第二類大河(汛期水面寬度大于30m)相應于上述小河各種情況,由于河岸阻力變小,n值略小,,,,,,,,,,,,,,,

1.斷面比較規整,無孤石或叢木,,,,,,,,,0.025,,,,,0.060,

2.斷面不規整,床面粗糙,,,,,,,,,0.035,,,,,0.100,

第三類洪水期灘地漫流,,,,,,,,,,,,,,,

1.草地無叢木,,,,,,,,,,,,,,,

(1)矮草,,,,,,,,,0.025,,0.030,,,0.035,

(2)長草,,,,,,,,,0.030,,0.035,,,0.050,

2.耕種面積,,,,,,,,,,,,,,,

(1)未熟莊家,,,,,,,,,0.020,,0.030,,,0.040,

(2)已熟成行莊稼,,,,,,,,,0.025,,0.035,,,0.045,

(3)已熟密植莊稼,,,,,,,,,0.030,,0.040,,,0.050,

3.灌木叢,,,,,,,,,,,,,,,

(1)雜草叢生,散布灌木,,,,,,,,,0.035,,0.050,,,0.070,

(2)稀疏灌木叢和樹(在冬季),,,,,,,,,0.035,,0.050,,,0.060,

(3)稀疏灌木叢和樹(在夏季),,,,,,,,,0.040,,0.060,,,0.080,

(4)中等密度灌木叢(在冬季),,,,,,,,,0.045,,0.070,,,0.110,

(5)中等密度灌木叢(在夏季),,,,,,,,,0.070,,0.100,,,0.160,

4.樹木,,,,,,,,,,,,,,,

(1)稠密柳樹,在夏季,不被水流沖刷,彎倒,,,,,,,,,0.110,,0.150,,,0.200,

(2)僅有樹木殘株,未出新枝,,,,,,,,,0.030,,0.040,,,0.050,

(3)僅有樹木殘株,生長很多新枝,,,,,,,,,0.050,,0.060,,,0.080,

(4)稠密樹木,很少矮樹,有少許生長于大樹下的草木,,,,,,,,,,,,,,,

洪水在樹枝以下,,,,,,,,,0.080,,0.100,,,0.120,

洪水達到樹枝,,,,,,,,,0.100,,0.120,,,0.160,

注:1.本表由美國霍爾頓編制。,,,,,,,,,,,,,,,

2.糙率n用曼寧公式計算,,,,,,,,,,,,,,,

天然河道糙率表,,,,,,,,,,,,,,,

類別,,,,河槽特征,,,,,,平均水深(m),,,,,"n

(曼寧公式)"

1,,,,半山區河流的平整河槽(礫石,卵石的河床),,,,,,2,,,,,0.024

,,,,,,,,,,4,,,,,0.023

,,,,,,,,,,6,,,,,0.023

,,,,,,,,,,10,,,,,0.023

2,,,,半山區河流中等彎曲的河槽,平原河流的平整河流槽(土質河床),,,,,,2,,,,,0.026

,,,,,,,,,,4,,,,,0.025

,,,,,,,,,,6,,,,,0.025

,,,,,,,,,,10,,,,,0.024

3,,,,半山區河流極彎曲的河槽,有支流和岔河,平原河流的中等彎曲的河槽,,,,,,2,,,,,0.031

,,,,,,,,,,4,,,,,0.029

,,,,,,,,,,6,,,,,0.029

,,,,,,,,,,10,,,,,0.028

4,,,,平原河流極度彎曲的河槽,有支流和岔河,山區河流的河槽(礫石,大礫石河床),,,,,,2,,,,,0.035

,,,,,,,,,,4,,,,,0.033

,,,,,,,,,,6,,,,,0.032

,,,,,,,,,,10,,,,,0.030

5,,,,平原河流極度彎曲的河槽,河岸有雜草,山區河流具有大礫石的河槽,淺的荒溪,,,,,,2,,,,,0.045

,,,,,,,,,,4,,,,,0.040

,,,,,,,,,,6,,,,,0.038

,,,,,,,,,,10,,,,,0.036

6,,,,呈均勻流的多石灘河段,無雜草的河段,,,,,,2,,,,,0.069

,,,,,,,,,,4,,,,,0.058

,,,,,,,,,,6,,,,,0.051

,,,,,,,,,,10,,,,,0.048

7,,,,中等情況的多石灘河段,25%蔓生雜草的河灘,,,,,,2,,,,,0.092

,,,,,,,,,,4,,,,,0.077

,,,,,,,,,,6,,,,,0.065

,,,,,,,,,,10,,,,,0.060

8,,,,具有大礫石的石灘段,個別部分水流方向特別不規則,50%蔓生雜草的河灘,,,,,,2,,,,,0.115

,,,,,,,,,,4,,,,,0.095

,,,,,,,,,,6,,,,,0.080

,,,,,,,,,,10,,,,,0.073

9,,,,75%蔓草雜生的河灘,,,,,,2,,,,,0.150

,,,,,,,,,,4,,,,,0.122

,,,,,,,,,,6,,,,,0.101

,,,,,,,,,,10,,,,,0.092

10,,,,100%蔓草雜生的河灘,,,,,,2,,,,,0.240

,,,,,,,,,,4,,,,,0.195

,,,,,,,,,,6,,,,,0.160

,,,,,,,,,,10,,,,,0.142

注:本表由前蘇聯玻爾達柯夫編制。,,,,,,,,,,,,,,,

天然河道糙率表—單式斷面或主槽(水位較高時),,,,,,,,,,,,,,,

類型,,河段特征,,,,,,,,,,,糙率n,,

,,河床組成及床面特性,,,,平面形態及水流形態,,岸壁特性,,,,,,,

Ⅰ,,河床為沙質,床面平整,,,,河段順直,斷面規整,水流暢通,,兩側岸壁為土質或土砂質,形狀較整齊,,,,,0.020-0.024,,

Ⅱ,,河床由巖板,砂礫或卵石組成,,,,河段順直,斷面規整,水流暢通,,兩側岸壁為土砂或石質,形狀較整齊,,,,,0.022-0.026,,

Ⅲ,1,河床為沙質,河底不太平順,,,,上游順直,下游接緩彎,水流不夠暢通,有局部回流,,兩側岸壁為黃土,長有雜草,,,,,0.025-0.029,,

,2,河底由砂礫或卵石組成,底坡較均勻,床面尚平整,,,,河道順直段較長,斷面較規整,水流較暢通,基本上無死水,斜流或回流,,兩側岸壁為土砂,巖石,略有雜草,小樹,形狀較整齊,,,,,0.025-0.029,,

Ⅳ,1,細沙,河底中有稀疏水草或水生植物,,,,河段不夠順直,上下游附近彎曲,有挑水壩,水流不暢通,,土質岸壁,一岸坍塌嚴重,為鋸齒狀,長有稀疏雜草及灌木,一岸坍塌,長有稠密雜草或蘆葦,,,,,0.030-0.034,,

,2,河床由礫石或卵石組成,底坡上尚均勻,床面不平整,,,,順直段距上彎道不遠,斷面尚且規整,水流尚且暢通,斜流或回流不明顯,,"一側岸壁為石質,陡坡,形狀尚且整齊,另一側岸壁為砂土,略有雜草,小

樹,形狀較整齊",,,,,0.030-0.034,,

Ⅴ,,河底由卵石,塊石組成,間有大漂石,底坡上均勻,床面不平整,,,,"順直段夾于兩彎道之間,距離不遠,斷面尚且規整,水流顯出斜流,回流或死水現

象",,兩側岸壁均為石質,陡坡,長有雜草,樹木,形狀尚且整齊,,,,,0.065-0.040,,

Ⅵ,,河床由卵石,塊石,亂石或大塊石,大亂石及大孤石組成,床面不平整,底頗有凸凹狀,,,,"河段不順直,上下游有急彎,或下游有急灘,深坑

等;河段處于S形順直段,不整齊,有阻塞或巖溶情況發育;水流不通暢,有斜流,回流,漩渦,死水現象;河段上游有彎道或為兩河匯

口,落差大,水流急,河道有嚴重堵塞,或兩側有深入河中的巖石,伴有深潭或回流等;上游為彎道,河段不順直,水行于深槽峽谷間,多阻塞,水流湍急,水聲較",,兩側岸壁為巖石及砂土,長有雜草,樹木,形狀尚且整齊;兩側岸壁為石砂質夾亂石,風化頁巖,崎嶇不平正,上面生長雜草,樹木,,,,,0.040-0.100,,

天然河道糙率表—灘地,,,,,,,,,,,,,,,

類型,,,灘地特征描述,,,,,,糙率n(曼寧公式),,,,,,

,,,平縱橫形態,,床質,,植被,,變化幅度,,,平均值,,,

Ⅰ,,,平面順直,縱斷平順,橫斷整齊,,土,沙質,淤泥,,基本上無植物或為已收割的麥地,,0.026-0.038,,,0.030,,,

Ⅱ,,,平面,縱面,橫面順直整齊,,土,沙質,,稀疏雜草,雜樹或矮小農作物,,0.030-0.050,,,0.040,,,

Ⅲ,,,平面,縱面,橫面尚且順直整齊,,砂礫,卵石灘或為土,沙質,,稀疏雜草,小雜樹,或高稈作物,,0.040-0.060,,,0.050,,,

Ⅳ,,,上下游有緩彎,縱面橫面尚且平坦,但有束水作用,水流不通暢,,土,沙質,,種有農作物,或有稀疏樹林,,0.050-0.070,,,0.060,,,

Ⅴ,,,平面不通暢,縱面橫面起伏不平,,土,沙質,,雜草,雜樹,或為水稻田,,0.060-0.090,,,0.075,,,

Ⅵ,,,平面尚且順直,縱面橫面起伏不平,有洼地,土埂等,,土,沙質,,長滿中密的雜草及農作物,,0.080-0.120,,,0.100,,,

Ⅶ,,,平面不通暢,縱面橫面起伏不平,有洼地,土埂等,,土,沙質,,3/4茂密的雜草,灌木,,0.100-0.160,,,0.130,,,

Ⅷ,,,平面不通暢,縱面橫面起伏不平,有洼地,土埂阻塞物,,土,沙質,,全斷面有稠密的植被,蘆柴或其他植物,,0.160-0.200,,,0.180,,,

"注:1.表中均列有三個方面的影響因素,河道糙率是三個方面因素和綜合作用結果。如實際情況與本表組合有變化時,糙率值應

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