渠道糙率取值以及水力計算土渠糙率渠道流量渠槽特征灌溉渠道泄（退）水渠道（立方米/秒）平整順直，養護良好0.0200.0225>20平整順直，養護一般0.02250.025渠床多石，雜草叢生，養護較差0.02500.0275平整順直，養護良好0.02250.02520～1平整順直，養護一般0.02500.0275渠床多石，雜草叢生，養護較差0.02750.030平整順直，養護良好0.02500.0275<1平整順直，養護一般0.02750.030渠床多石，雜草叢生，養護較差0.0300.035石渠糙率渠槽表面特征糙率經過良好修整0.0250經過中等修整無凸出部分0.0300經過中等修整有凸出部分0.0330無經修整有凸出部分0.0350～0.0450防滲襯砌渠槽糙率防滲襯砌結構類別及特征糙率漿砌料石、石板0.0150～0.0230漿砌塊石0.0200～0.0250干砌塊石0.0250～0.0330砌石漿砌卵石0.0230～0.0275干砌卵石，砌工良好0.0250～0.0325干砌卵石，砌工一般0.0275～0.0375干砌卵石，砌工粗糙0.0325～0.0425抹光的水泥沙漿面0.0120～0.0130金屬模板澆筑，平整順直，表面光0.0120～0.0140滑刨光木模板澆筑，表面一般0.0150混凝土表面粗糙，縫口不齊0.0170修整及養護較差0.0180預制板砌筑0.0160～0.0180預制渠槽0.0120～0.0160梯形及矩形渠道的水力計算示意圖梯形及矩形水深流量計算表（底寬1米、邊坡m＝1.5n＝0.025i＝1/3000）ARCQhχ流速(面(水（謝（m3i（mmb（m）n（濕（m/s積）力半才系/s））周）m）m2徑）m數）0.001.20.026.50.020.11.000.111.320.090.140352530.000.11.20.028.10.031.000.181.480.120.1803552510.001.20.029.20.050.21.000.251.640.150.210352530.000.21.20.030.10.081.000.331.800.180.2303552520.110.000.31.21.000.00.411.960.2130.80.260352550.000.31.20.031.40.141.000.502.120.240.2803552570.001.20.032.00.180.41.000.602.280.260.300352520.000.41.20.032.50.221.000.702.440.290.3203552510.001.20.032.90.270.51.000.812.600.310.340352550.000.51.20.033.30.331.000.932.760.340.3503552550.001.20.033.70.390.61.001.052.920.360.370352530.000.61.20.034.00.451.001.183.080.380.3803552580.001.20.034.40.520.71.001.313.240.400.400352510.000.71.20.034.70.601.001.453.400.430.4103552510.001.20.035.00.690.81.001.603.560.450.430352510.780.000.81.21.000.01.753.720.4735.20.4403552580.001.20.035.50.870.91.001.913.880.490.460352550.000.91.20.035.80.971.002.084.040.510.4703552500.001.20.036.01.0811.002.254.200.540.480352550.001.01.20.036.21.201.002.434.360.560.4903552580.001.20.036.51.321.11.002.614.520.580.510352500.001.11.20.036.71.451.002.804.680.600.5203552520.001.20.036.91.591.21.003.004.840.620.530352530.001.21.20.037.11.741.003.205.000.640.5403552540.001.20.037.31.891.31.003.415.160.660.550352530.001.31.20.037.52.051.003.635.320.680.5703552532.220.001.41.21.000.03.855.480.7037.70.580352510.001.41.20.037.82.401.004.085.640.720.5903552590.001.20.038.02.581.51.004.315.800.740.600352570.001.51.20.038.22.781.004.555.960.760.6103552540.001.20.038.42.981.61.004.806.120.780.620352510.001.61.20.038.53.191.005.056.280.800.6303552570.001.20.038.73.411.71.005.316.440.820.640352530.001.71.20.038.83.641.005.586.600.840.6503552590.001.20.039.03.881.81.005.856.760.870.660352540.001.81.20.039.24.131.006.136.920.890.6703552500.001.20.039.34.381.91.006.417.080.910.680352544.650.001.91.21.000.06.707.240.9339.40.6903 5 5 25 9梯形渠道水深流量計算可采用相關軟件計算，如無軟件，可采用電子表格（MicrosoftExcel）計算，如計算其它形式的斷面流量，只須在電子表格中修改水深（h）、比降（i）、底寬、糙率（n）、坡比（m）（矩形為0）幾個參數即可。（計算的電子表格由農業開發辦提供）。如已知流量（Q）求水深（h），可在原計算表格中，采用電子表格中“工具”菜單下的“單變量求解”工具求得。也可采用水力學提供的諾模圖進行查算。形渠道計算斷面示意圖形渠道水深流量計算可采用軟件計算，也可以采用電子表格（MicrosoftExcel）計算，如計算其它形式的斷面流量，只須在電子表格中修改用陰影標注的部分。如已知流量（Q）求水深（h），可在原計算表格中，采用電子表格中“工具”菜單下的“單變量求解”工具求得。U60流量計算表U形槽圓弧半徑（r）m 0.6U形槽直線段坡比m 0.249U形渠道Kr值 0.39U形渠道底部直線段寬 0.5度bU形槽最大水深（H）m 1.54圓弧段最大水深（h1） 0.46m直線段最小底寬（b1） 1.16圓弧段最大圓心角（弧 2.65度）U形槽最大圓弧段面積 0.39（m2）U形槽最大圓弧弧長1.59（m）Q(m3/s)h(水深半徑rin（糙角度(弧面積(m濕周水力半謝才系流速m）（m）率）度）2)（m）徑數（m/s）0.0650.1000.6000.000.0121.1710.0951.2030.07954.5860.68620.2340.2000.6000.000.0121.6820.2241.5090.14860.6321.04420.4910.3000.6000.000.0122.0940.3711.7570.21164.3111.32220.8210.4000.6000.000.0122.4620.5301.9770.26866.9151.54921.2100.5000.6000.000.0122.6540.6962.1850.31968.8701.73821.6440.6000.6000.000.0122.6540.8672.3910.36370.3751.89622.1170.7000.6000.000.0122.6541.0432.5970.40271.5842.02922.6270.8000.6000.000.0122.6541.2252.8030.43772.5902.14623.1730.9000.6000.000.0122.6541.4113.0090.46973.4482.24923.7511.