不同河流、明渠等的粗糙度-糙率取值n表

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(qū)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(qū)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(yīng)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(guī)整，無孤石或叢木,,,,,,,,,0.025,,,,,0.060,

2.斷面不規(guī)整，床面粗糙,,,,,,,,,0.035,,,,,0.100,

第三類洪水期灘地漫流,,,,,,,,,,,,,,,

1.草地?zé)o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(dá)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(jì)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(qū)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(qū)河流中等彎曲的河槽，平原河流的平整河流槽（土質(zhì)河床）,,,,,,2,,,,,0.026

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

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

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

3,,,,半山區(qū)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(qū)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(qū)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(guī)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(lián)玻爾達(dá)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(tài)及水流形態(tài),,岸壁特性,,,,,,,

Ⅰ,,河床為沙質(zhì)，床面平整,,,,河段順直，斷面規(guī)整，水流暢通,,兩側(cè)岸壁為土質(zhì)或土砂質(zhì)，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(guī)整，水流暢通,,兩側(cè)岸壁為土砂或石質(zhì)，形狀較整齊,,,,,0.022-0.026,,

Ⅲ,1,河床為沙質(zhì)，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(cè)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(guī)整，水流較暢通，基本上無死水，斜流或回流,,兩側(cè)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(xì)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(zhì)岸壁，一岸坍塌嚴(yán)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(yuǎn)，斷面尚且規(guī)整，水流尚且暢通，斜流或回流不明顯,,"一側(cè)岸壁為石質(zhì)，陡坡，形狀尚且整齊，另一側(cè)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(yuǎn)，斷面尚且規(guī)整，水流顯出斜流，回流或死水現(xiàn)

象",,兩側(cè)岸壁均為石質(zhì)，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(fā)育；水流不通暢，有斜流，回流，漩渦，死水現(xiàn)象；河段上游有彎道或?yàn)閮珊訁R

口，落差大，水流急，河道有嚴(yán)重堵塞，或兩側(cè)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(cè)岸壁為巖石及砂土，長有雜草，樹木，形狀尚且整齊；兩側(cè)岸壁為石砂質(zhì)夾亂石，風(fēng)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(tài),,床質(zhì),,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(zhì)，淤泥,,基本上無植物或?yàn)橐咽崭畹柠湹?,0.026-0.038,,,0.030,,,

Ⅱ,,,平面，縱面，橫面順直整齊,,土，沙質(zhì),,稀疏雜草，雜樹或矮小農(nóng)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?yàn)橥粒迟|(zhì),,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(zhì),,種有農(nóng)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(zhì),,雜草，雜樹，或?yàn)樗咎?,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(zhì),,長滿中密的雜草及農(nóng)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(zhì),,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(zhì),,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(jié)果。如實(shí)際情況與本表組合有變化時，糙率值應(yīng)