馬清河灌區(qū)灌溉系統(tǒng)規(guī)劃設(shè)計

馬清河灌區(qū)灌溉系統(tǒng)規(guī)劃設(shè)計馬清河灌區(qū)灌溉系統(tǒng)規(guī)劃設(shè)計學(xué)校：揚州大學(xué)專業(yè)：水利水電工程班級：姓名：指導(dǎo)老師：目錄TOCTOCTOC1基本資料 基本資料1.1概況灌區(qū)位于界榮山以南，馬清河以北，總面積（20m等高線以下的）約12萬畝。氣候溫和，無霜期長，適宜于農(nóng)作物生長。年平均氣溫16.5℃，多年平均蒸發(fā)量1065mm，多年平均降水量1112mm，馬清河灌區(qū)地形圖見附圖1。灌區(qū)人口總數(shù)約8萬，勞動力1.9萬。申溪以西屬興隆鄉(xiāng)，以東屬大勝鄉(xiāng)。根據(jù)農(nóng)業(yè)規(guī)劃，界榮山上以林、牧、副業(yè)為主，馬頭山以林為主，20m等高線以下則以大田作物為主，種植稻、麥、棉、豆等作物。灌區(qū)上游土質(zhì)屬中壤，下游龍尾河一帶屬輕砂壤土。地下水埋深一般為4～5m，土壤及地下水的pH值屬中性，無鹽堿化威脅。界榮山、龍尾山等屬土質(zhì)丘陵，表土屬中粘壤土，地表5～6m以下為巖層，申溪及吳家溝等溝溪均有巖石露頭，馬頭山陳村以南至馬清河邊巖石遍布地表。吳家溝等溝溪縱坡較大，下切較深，一般為7～8m，上游寬50～60m，下游寬70～90m，遇暴雨時易暴發(fā)洪水，近年來已在各溝、溪上游修建多處小型水庫，山洪已基本得到控制，對灌區(qū)無威脅。馬清河灌區(qū)為馬清河流域規(guī)劃的組成部分。根據(jù)規(guī)劃要求，已在興隆峪上游20km處建大型水庫一座，壩頂高程50.2m，正常水位43.0m，興利庫容1.2×108m3，總庫容2.3×108m3。馬清河灌區(qū)擬在該水庫下游斷面處修建攔河壩式取水樞紐，引取水庫水發(fā)電尾水進行灌溉。斷面處河底高程30m，砂、卵石覆蓋層厚2.5m，下為基巖，河道比降1/100，河底寬82m，河面寬120m。水庫所供之水水質(zhì)良好，含沙量極微，水量亦能完全滿足灌區(qū)用水要求。1.2氣象根據(jù)當(dāng)?shù)貧庀笳举Y料，設(shè)計的中等干旱年（相當(dāng)于1972年）4～11月水面蒸發(fā)量（80cm口徑蒸發(fā)皿）及降水量見表1-1及表1-2。

表1-1設(shè)計年蒸發(fā)量統(tǒng)計月份4567蒸發(fā)量（mm）97.5118.0143.7174.9月份891011蒸發(fā)量（mm）196.5144.7101.175.6表1-2設(shè)計年降水量統(tǒng)計(mm)日月份4567891017.64.6212.717.418.533.41.97.3492.055.31.210.864.87.92.878.628.582.5919.1103.6112.52.1121.96.4137.52.31412.11.91.91510.0166.04.13.532.81724.5181.3191.6204.312.611.5211.818.5222.110.649.22.53.6231.410.74.52435.47.4256.2261.5271.1281.53.729307.7313.6月計72.9108.5107.339.825.037.3103.51.3種植計劃及灌溉經(jīng)驗灌區(qū)以種植水稻為主，兼有少量旱作物，各種作物種植比例見表1-3。表1-3作物種植比例作物旱稻中稻雙季晚稻棉花種植比例（%）50305020根據(jù)該地區(qū)灌溉試驗站觀測資料，土壤空隙率為48%（占土體的%），田間持水率為88%（占空隙%）。設(shè)計年（1972）早稻全生育期需水系數(shù)=1.0，泡田定額為70m3/畝；棉花計劃產(chǎn)量120kg，需水系數(shù)k=2.67m3/kg，土壤適宜含水率上限為88%，下限為61.6%（占空隙%），播前灌計劃濕潤層深為0.4m，播前計劃濕潤層平均含水率65.3%（占空隙%），播種時計劃濕潤層土壤實際儲水量為102m3/畝。早稻及棉花的基本觀測數(shù)據(jù)如表1-4及表1-5所示；中稻及晚稻的豐產(chǎn)灌溉制度計算見表1-6。表1-4早稻試驗基本數(shù)據(jù)生育階段復(fù)苗分蘗前分蘗后孕穗抽穗乳熟黃熟全生育期起止日期(日/月)25/4~4/55/5~14/515/5~1/62/6~16/617/6~30/61/7~11/712/7~20/725/4~20/7天數(shù)101018151411987模比系數(shù)(%)78182521138100田間允許水層深(mm)10-30-5010-40-8020-50-9020-50-10020-50-9010-40-50濕潤滲透強度(mm/d)1.31.31.31.31.31.31.3表1-5棉花試驗基本數(shù)據(jù)生育階段幼苗期現(xiàn)蕾期開花結(jié)鈴期吐絮期全生育期起止日期(日/月)21/4~16/617/6~28/729/7~26/827/8~6/1121/4~6/11模比系數(shù)(%下水補給量占作物需水量的(%)10202225計劃濕潤層深(m)0.4~0.50.5~0.60.6~0.70.7表1-6中稻、雙季晚稻設(shè)計年豐產(chǎn)灌溉制度中稻雙季晚稻灌水次序灌水時間（日/月）灌水定額（/畝）灌水次序灌水時間（日/月）灌水定額（/畝）1（泡田）7/5751（泡田）19/770226/525227/71534/62531/825410/62547/820520/630512/82562/730623/83078/730727/830814/730831/830922/73096/9301029/7251012/9301110/8201119/9301230/920灌溉定額345（/畝）灌溉定額355（/畝）1.4灌區(qū)開發(fā)的必要性和可行性1.灌區(qū)開發(fā)的必要性分析(1)從作物需水要求來說，該灌區(qū)灌溉面積近12萬畝，地形相對平坦，適宜農(nóng)作物的成長，其種植的作物包括有早稻、中稻、雙季稻和棉花，都是相對來說耗水的經(jīng)濟作物，種植比例為50:30:50:20。多年平均蒸發(fā)量和降雨量基本持平，現(xiàn)有的自然條件不能滿足作物的需水要求。(2)就目前的灌溉與排水條件來說，在灌區(qū)有兩條河流，但都是流量比較小的河流且分布不均勻，無法滿足整個灌區(qū)的灌水要求，因此修建灌溉系統(tǒng)十分必要。2.灌區(qū)開發(fā)的可行性分析就灌區(qū)開發(fā)的有利條件來說，該灌區(qū)位于河流沖擊所形成的平原帶，其正南方有馬清河通過，而在馬清河上游有一興利庫容1.2×1380m,總庫容2.3×1380m的水庫，取水水源方便、水質(zhì)良好，符合灌溉的基本條件。其次引取水庫水發(fā)電則利用尾水進行灌溉，既考慮了資源充分利用，又兼顧經(jīng)濟效益。綜上所述，該地域修建灌溉系統(tǒng)，實際上必要，技術(shù)上可行，同時能實現(xiàn)經(jīng)濟效益、社會效益、生態(tài)效益的統(tǒng)一。

2早稻及棉花的灌溉制度計算2.1早稻的灌溉制度計算由已知的氣象資料可知，在早稻的全生育期的蒸發(fā)量為:所以可得各生育階段的需水量，繼而可得出逐日耗水量,計算結(jié)果如表2-1。表2-1逐日耗水量計算表生育期復(fù)苗分蘗前分蘗后孕穗抽穗乳熟黃熟全生育期起止日月25/4~4/55/5~14/515/5~1/62/6~16/617/6~30/61/7~11/712/7~20/725/4~20/7天數(shù)101018151411987模比系數(shù)﹪78182521138100階段需水量(mm)27.5831.5270.9398.5282.7551.2331.52394.06階段滲漏量(mm)131323.419.518.214.311.7113.1階段耗水量(mm)40.5844.5294.33118.02100.9565.5343.22507.16逐日耗水量(mm)4.064.455.247.877.215.964.8注：稻田滲漏量為1mm/d當(dāng)淹灌水層減去逐日耗水量，加上逐日降雨量后若小于最小田間允許最小水層深度則設(shè)計灌水，當(dāng)大于最大田間允許水層深度則設(shè)計排水。水量平衡方程：早稻生育期灌溉制度計算結(jié)果見表2-2。表2-2早稻生育期灌溉制度計算表日期生育期設(shè)計淹灌水層(mm)逐日耗水量(mm)逐日降雨(mm)淹灌水層變化(mm)灌水量(mm)排水量(mm)月日4242025復(fù)苗期10-30-504.0615.942611.882727.8220281.525.262921.23017.145113.08229.022033.428.364226.35分蘗期10-40-804.451.223.0567.926.5728.550.55846.1941.651037.2112.535.25126.437.21332.751428.315分蘗末20-50-905.2448.062516648.821724.568.081862.841957.62052.362147.122210.652.482310.757.942452.72547.462642.22271.138.08283.736.542931.33026.063145.82256140.5862孕穗20-50-1007.8717.450.1131.944.14436.27528.4620.53747.6635839.79931.921024.051146.18301238.311330.44141.924.471546.6301638.7317抽穗20-50-907.2131.521824.311947.1302039.892132.682249.274.672367.462435.4905.652582.79261.577.082769.872862.662955.453048.2471乳熟10-40-505.9642.28236.32330.36424.4518.44612.48736.5230830.56924.61018.641112.6812黃熟濕潤4.87.88133.081415103.48164.12.7817181920∑463.97217.32455.65校核：與7月11日淹灌水層基本相符?？傻迷绲旧谠O(shè)計灌溉制度，見表2-3。表2-3早稻灌溉制度表灌水次數(shù)灌水日期灌水定額mm/畝14月27日2013.325月2日2013.335月15日2516.745月31日2516.756月7日3523.366月11日3020.076月15日3020.086月19日3020.097月5日3523.3107月10日3020.02.2棉花的灌溉制度計算棉花全生育期的需水量為：即其各生育階段的需水量為：各生育階段地下水補給量為：由于計劃濕潤層增加而增加的水量：計劃濕潤層的最大、最小蓄水量：計劃濕潤層深度H(m)：有效降雨量，用降雨入滲系數(shù)α法求?。害恋倪x取按表2-4計：表2-4α取值表次降雨量＜5mm5~50mm＞50mmα01.0~0.80.7~0.8棉花灌溉制度表見表2-5。表2-4棉花灌溉定額計算表日期生育階段計劃濕潤層深4/20幼苗期0.400112.7078.894.30102.004/210.400112.7078.891.800.000.101.01101.094/220.402113.1979.232.100.420.101.01100.604/230.404113.6879.581.400.420.101.01100.114/240.405114.1879.9300.420.101.0199.624/250.407114.6780.2700.420.101.0199.134/260.409115.1780.6200.420.101.0198.644/270.411115.6680.9600.420.101.0198.154/280.412116.1681.311.500.420.101.0197.664/290.414116.6581.6600.420.101.0197.174/300.416117.1482.0000.420.101.0196.685/10.418117.6482.3500.420.101.0196.185/20.419118.1382.6900.420.101.0195.695/30.421118.6383.043.400.420.101.0195.205/40.423119.1283.39200.420.101.0194.715/50.425119.6283.731.200.420.101.0194.225/60.426120.1184.087.94.740.420.101.0198.475/70.428120.6084.4228.517.10.420.101.01115.085/80.430121.1084.7700.420.101.01114.595/90.432121.5985.1200.420.101.01114.105/100.433122.0985.4600.420.101.01113.615/110.435122.5885.812.500.420.101.01113.125/120.437123.0886.156.43.840.420.101.01116.475/130.439123.5786.5000.420.101.01115.985/140.440124.0686.8500.420.101.01115.495/150.442124.5687.1900.420.101.01115.005/160.444125.0587.5463.60.420.101.01118.115/170.446125.5587.8824.514.70.420.101.01125.556.775/180.447126.0488.2300.420.101.01125.065/190.449126.5488.5800.420.101.01124.575/200.451127.0388.9200.420.101.01124.085/210.453127.5289.2700.420.101.01123.595/220.454128.0289.6110.66.360.420.101.01128.021.445/230.456128.5189.9610.76.420.420.101.01128.515.445/240.458129.0190.3100.420.101.01128.025/250.460129.5090.6500.420.101.01127.535/260.461130.0091.0000.420.101.01127.045/270.463130.4991.341.100.420.101.01126.555/280.465130.9891.693.700.420.101.01126.065/290.467131.4892.0400.420.101.01125.575/300.468131.9792.3800.420.101.01125.085/310.470132.4792.7300.420.101.01124.596/10.472132.9693.0700.420.101.01124.106/20.474133.4693.4217.410.440.420.101.01133.460.596/30.475133.9593.771.900.420.101.01132.976/40.477134.4494.1100.420.101.01132.486/50.479134.9494.4600.420.101.01131.986/60.481135.4394.8000.420.101.01131.496/70.482135.9395.1500.420.101.01131.006/80.484136.4295.5000.420.101.01130.516/90.486136.9295.8400.420.101.01130.026/100.488137.4196.1900.420.101.01129.536/110.489137.9096.5300.420.101.01129.046/120.491138.4096.8800.420.101.01128.556/130.493138.8997.2300.420.101.01128.066/140.495139.3997.571.900.420.101.01127.576/150.496139.8897.9200.420.101.01127.086/160.498140.3898.2600.420.101.01126.596/17現(xiàn)蕾期0.500140.8798.6100.420.462.29125.186/180.502141.5499.0800.570.462.29123.926/190.505142.2199.5500.570.462.29122.666/200.507142.88100.0200.570.462.29121.406/210.510143.55100.4900.570.462.29120.146/220.512144.22100.9649.229.520.570.462.29144.224.176/230.514144.90101.4300.570.462.29142.966/240.517145.57101.9035.421.240.570.462.29145.5717.386/250.519146.24102.3700.570.462.29144.316/260.521146.91102.841.500.570.462.29143.046/270.524147.58103.3000.570.462.29141.786/280.526148.25103.7700.570.462.29140.526/290.529148.92104.2400.570.462.29139.266/300.531149.59104.7100.570.462.29138.007/10.533150.26105.1800.570.462.29136.747/20.536150.93105.6500.570.462.29135.487/30.538151.60106.1200.570.462.29134.227/40.540152.27106.5900.570.462.29132.967/50.543152.95107.0600.570.462.29131.707/60.545153.62107.5300.570.462.29130.447/70.548154.29108.0000.570.462.29129.187/80.550154.96108.4700.570.462.29127.927/90.552155.63108.9400.570.462.29126.667/100.555156.30109.4100.570.462.29125.407/110.557156.97109.8800.570.462.29124.147/120.560157.64110.3500.570.462.29122.887/130.562158.31110.8200.570.462.29121.617/140.564158.98111.2900.570.462.29120.357/150.567159.65111.761060.570.462.29125.097/160.569160.32112.234.100.570.462.29123.837/170.571160.99112.7000.570.462.29122.577/180.574161.67113.1700.570.462.29121.317/190.576162.34113.6400.570.462.29120.057/200.579163.01114.1100.570.462.29118.797/210.581163.68114.5700.570.462.29117.537/220.583164.35115.042.500.570.462.29116.277/230.586165.02115.514.500.570.462.29160.01457/240.588165.69115.987.44.440.570.462.29163.197/250.590166.36116.4500.570.462.29161.937/260.593167.03116.9200.570.462.29160.677/270.595167.70117.3900.570.462.29159.417/280.598168.37117.8600.570.462.29158.157/29開花結(jié)鈴期0.600169.04118.3300.570.582.65156.657/300.603170.02119.017.74.620.830.582.65160.037/310.607170.99119.693.600.830.582.65158.788/10.610171.96120.3700.830.582.65157.548/20.614172.93121.0500.830.582.65156.308/30.617173.90121.7300.830.582.65155.068/40.621174.87122.4100.830.582.65153.818/50.624175.85123.0910.86.480.830.582.65159.058/60.628176.82123.7700.830.582.65157.818/70.631177.79124.4500.830.582.65156.578/80.634178.76125.1300.830.582.65155.328/90.638179.73125.8100.830.582.65154.088/100.641180.70126.4900.830.582.65152.848/110.645181.67127.1700.830.582.65151.608/120.648182.65127.8500.830.582.65150.368/130.652183.62128.5300.830.582.65149.118/140.655184.59129.2100.830.582.65147.878/150.659185.56129.8900.830.582.65146.638/160.662186.53130.5700.830.582.65145.398/170.666187.50131.2500.830.582.65144.148/180.669188.47131.9300.830.582.65142.908/190.672189.45132.611.600.830.582.65141.668/200.676190.42133.2912.67.560.830.582.65147.988/210.679191.39133.9700.830.582.65146.748/220.683192.36134.6500.830.582.65145.498/230.686193.33135.3300.830.582.65144.258/240.690194.30136.0100.830.582.65143.018/250.693195.28136.6900.830.582.65141.778/260.697196.25137.3700.830.582.65140.528/27吐絮期0.700197.22138.0500.830.311.25140.428/280.700197.22138.0500.000.311.25139.488/290.700197.22138.0500.000.311.25138.558/300.700197.22138.0500.000.311.25192.61558/310.700197.22138.0500.000.311.25191.689/10.700197.22138.0500.000.311.25190.749/20.700197.22138.0500.000.311.25189.819/30.700197.22138.057.34.380.000.311.25193.259/40.700197.22138.0500.000.311.25192.329/50.700197.22138.0500.000.311.25191.389/60.700197.22138.0500.000.311.25190.459/70.700197.22138.0500.000.311.25189.529/80.700197.22138.0500.000.311.25188.589/90.700197.22138.0500.000.311.25187.659/100.700197.22138.0500.000.311.25186.719/110.700197.22138.052.100.000.311.25185.789/120.700197.22138.0500.000.311.25184.849/130.700197.22138.052.300.000.311.25183.919/140.700197.22138.0500.000.311.25182.979/150.700197.22138.0500.000.311.25182.049/160.700197.22138.053.500.000.311.25181.119/170.700197.22138.0500.000.311.25180.179/180.700197.22138.0500.000.311.25179.249/190.700197.22138.0500.000.311.25178.309/200.700197.22138.0500.000.311.25177.379/210.700197.22138.0518.511.10.000.311.25187.539/220.700197.22138.053.600.000.311.25186.609/230.700197.22138.0500.000.311.25185.669/240.700197.22138.0500.000.311.25184.739/250.700197.22138.0500.000.311.25183.799/260.700197.22138.0500.000.311.25182.869/270.700197.22138.0500.000.311.25181.939/280.700197.22138.0500.000.311.25180.999/290.700197.22138.0500.000.311.25180.069/300.700197.22138.0500.000.311.25179.1210/10.700197.22138.054.600.000.311.25178.1910/20.700197.22138.0518.511.10.000.311.25188.3510/30.700197.22138.0500.000.311.25187.4210/40.700197.22138.0500.000.311.25186.4810/50.700197.22138.0500.000.311.25185.5510/60.700197.22138.052.800.000.311.25184.6210/70.700197.22138.0500.000.311.25183.6810/80.700197.22138.052.500.000.311.25182.7510/90.700197.22138.0519.111.460.000.311.25193.2710/100.700197.22138.053.600.000.311.25192.3410/110.700197.22138.0500.000.311.25191.4010/120.700197.22138.0500.000.311.25190.4710/130.700197.22138.0500.000.311.25189.5310/140.700197.22138.051.900.000.311.25188.6010/150.700197.22138.0500.000.311.25187.6610/160.700197.22138.0532.819.680.000.311.25197.229.1910/170.700197.22138.0500.000.311.25196.2810/180.700197.22138.0500.000.311.25195.3510/190.700197.22138.0500.000.311.25194.4210/200.700197.22138.0511.56.90.000.311.25197.223.1610/210.700197.22138.0500.000.311.25196.2810/220.700197.22138.0500.000.311.25195.3510/230.700197.22138.0500.000.311.25194.4210/240.700197.22138.0500.000.311.25193.4810/250.700197.22138.056.23.720.000.311.25196.2710/260.700197.22138.0500.000.311.25195.3310/270.700197.22138.0500.000.311.25194.4010/280.700197.22138.0500.000.311.25193.4610/290.700197.22138.0500.000.311.25192.5310/300.700197.22138.0500.000.311.25191.5910/310.700197.22138.0500.000.311.25190.6611/10.700197.22138.0500.000.311.25189.7211/20.700197.22138.0500.000.311.25188.7911/30.700197.22138.0500.000.311.25187.8611/40.700197.22138.0500.000.311.25186.9211/50.700197.22138.0500.000.311.25185.9911/60.700197.22138.0500.000.311.25185.05

3灌水率計算根據(jù)所計算得的早稻、棉花及給出的中稻、雙季晚稻的灌溉制度以及作物比例分別計算出其灌溉率，各次灌水的灌水率為：計算列入表3-1。表3-1初步灌水率計算表作物種植比例%灌水次數(shù)灌水時間（月/日）灌水定額延續(xù)時間（d）灌水率/（s·萬畝)早稻501(泡田）4月19日70.060.6824月27日13.340.1935月2日13.340.1945月15日16.740.2455月31日16.740.2466月4日23.350.2776月11日20.040.2986月15日20.040.2996月19日20.040.29107月7日20.050.23中稻301(泡田）5月7日75.060.4325月26日25.040.2236月4日25.050.1746月10日25.050.1756月20日30.040.2667月2日30.040.2677月8日30.040.2687月14日30.040.2697月22日30.040.26107月29日25.040.22118月10日20.040.17雙季晚稻501(泡田）7月19日70.060.6827月27日15.040.2238月1日25.040.3648月7日20.040.2958月12日25.040.3668月23日30.040.4378月27日30.040.4388月31日30.050.3599月6日30.050.35109月12日30.050.35119月19日30.040.43129月30日20.040.29棉花2017月23日45.070.1528月30日55.070.18將所得灌水率繪在方格紙上得初步灌水率圖,如圖3-1，后經(jīng)修正后得最后的灌水率圖，如圖3-2，選取延續(xù)時間較長的最大灌水率值。圖3-1初步灌水模數(shù)圖圖3-2修正后灌水模數(shù)圖取修正后的灌水率為0.41m3/(s*萬畝)。

4灌排渠系及渠系建筑物規(guī)劃布置4.1水源與取水口選擇灌區(qū)的水源主要是以馬清河為灌溉水源。馬清河上游，水位較高，河岸堅硬，河槽較穩(wěn)定，還有一座水庫水質(zhì)良好，含沙量極微，灌區(qū)上游土質(zhì)屬中壤，下游龍尾河一帶屬輕砂壤土。地下水埋深一般為4~5m，土壤及地下水的PH值屬中性，無鹽堿化威脅。取水口宜取在凹岸中點偏下游處，取水口在這里可利用橫向環(huán)流作用，使主流接近取水口，加大進流量，有效防止泥沙淤積渠口和進入渠道，避免水直接沖擊渠道，有利于渠道的保護。4.2各級渠道與排水溝布置本灌區(qū)灌溉渠道分為干、支、斗、農(nóng)四級固定渠道。本灌區(qū)屬于小坡度地區(qū)。一支布置在整個灌區(qū)的西面，與等高線成一定的角度。二支布置在吳家溝和申溪之間，三支布置在小坳與新村連線，四支布置在枯石村與陳留連線，即整個灌區(qū)由四條支渠控制。第三支渠灌溉面積適中，可作為典型支渠，該支渠有12條斗渠，斗渠長1800m。每條斗渠有8條農(nóng)渠，長750m,間距250m。4.3渠系建筑物布置渠系建筑物是指與渠道配套的水閘、涵洞、橋梁、渡槽、倒虹吸、跌水、陡坡等建筑物。1.渠系建筑物的選型與布置原則(1)盡量采用定型設(shè)計和裝配式建筑物；(2)盡量利用當(dāng)?shù)夭牧闲藿ǎ?3)渠系建筑物的位置應(yīng)根據(jù)渠系平面布置圖、渠道縱橫斷面圖及當(dāng)?shù)厍闆r合理布局；(4)渠系建筑物應(yīng)滿足渠道輸水、配水、量水、泄水和防洪等要求，保證渠道正常運行，最大限度地滿足作物需水要求；(5)渠系建筑物布置盡可能集中，聯(lián)合修建，形成樞紐，降低造價，便于管理；(6)布置渠系建筑物應(yīng)使水流流態(tài)穩(wěn)定，水頭損失小。2.主要的渠系建筑物(1)引水建筑物進水閘：在渠道取水處，調(diào)節(jié)干渠的進水流量，滿足灌溉對水位、流量的要求。(2)配水建筑物1）分水閘：布置在各支渠、斗渠和農(nóng)渠渠首。上級渠道的分水閘就是下級渠道的進水閘。分水閘的作用是控制和調(diào)節(jié)向下級渠道的配水流量，其結(jié)構(gòu)形式有開敞式和涵洞式兩種。2）節(jié)制閘：垂直于渠道中心線布置，其作用是控制渠道水位或流量。下列情況需要設(shè)置節(jié)制閘：①在上級渠水位不能保證下級渠正常引水時，需在上級渠建節(jié)制閘抬高水位，保證下級渠引水。②實行輪灌時，在輪灌組分界處需設(shè)節(jié)制閘。③在重要建筑物或險工渠段前需聯(lián)合修建節(jié)制閘和泄水閘，以防止漫溢，保證建筑物和渠道的安全。3.交叉建筑物常見的交叉建筑物有：隧洞、渡槽、倒虹吸、涵洞、橋梁等。(1)隧洞：當(dāng)渠道遇到山崗時，或因石質(zhì)堅硬，或因開挖工程量過大，往往不能采用深挖方渠道，如沿等高線繞行，渠道線路又過長，工程量仍然較大，而且增加了水頭損失。在這種情況下，可選擇山崗單薄的地方鑿洞而過。(2)倒虹吸：渠道穿過河溝、道路時，如果渠道水位高出河溝洪水位，但渠底高程卻低于河溝洪水位時；或渠底高程雖高于路面，但凈空不能滿足交通要求時，就要用壓力管道代替渠道，從河溝、道路下面通過，壓力管道的軸線向下彎曲，形似倒虹。(3)渡槽：渠道穿過河溝、道路時，如果渠底高于河溝最高洪水位或渠底高于路面的凈空大于行駛車輛要求的安全高度時，可架設(shè)渡槽；渠道穿越洼地時，如采用高填方渠道工程量太大，也可采用渡槽。(4)涵洞：渠道與道路相交，渠道水位低于路面，而且流量較小時，常在路面下面埋設(shè)平直的管道，叫做涵洞。(5)橋梁：渠道與道路相交，渠道水位低于路面，而且流量較大，水面較寬時，要在渠道上修建橋梁，滿足交通要求。4.銜接建筑物當(dāng)渠道經(jīng)過坡度較大的地段時，為防止渠道沖刷，保持渠道的設(shè)計比降，就把渠道分成上、下兩段，中間用銜接建筑物聯(lián)結(jié)，常見的銜接建筑物有跌水或陡坡。（1）跌水：水位落差小于３ｍ時，宜建跌水。（2）陡坡：水位落差大于３ｍ時，宜建陡坡。5.泄水建筑物用于排除渠道中余水或入渠洪水。（1）退水閘：布置在較大的干、支、斗渠末端，以排泄渠中余水（防止滋生雜草和蚊蟲）。

（2）泄水閘：與節(jié)制閘聯(lián)合修建，保護重要建筑物和險工渠段。6.量水建筑物（1）利用閘、涵、渡槽等量水。在干支渠上量水一般利用這些渠系建筑物量水。（2）利用特設(shè)計量水設(shè)備量水。如三角堰、梯形堰、巴歇爾量水槽、噴嘴等。一般斗、農(nóng)渠上可采用特設(shè)量水設(shè)備。渠系建筑物的布置具體見干渠縱斷面附圖1.

5水位推算5.1初擬各級渠道比降一般干渠比降為1/10000左右，支渠比降為1/5000左右，斗渠比降為1/2000左右，農(nóng)渠比降為1/1000左右。5.2選擇地面控制點地面控制點即灌溉區(qū)域內(nèi)最難控制的點，可通過比較渠道比降和地面比降來確定控制點在渠道首部，還是在渠道末端。一般通過以下步驟確定控制點位置：若干渠比降≥干渠沿線地面比降，則控制點位于灌區(qū)尾部，反之位于灌區(qū)首部；若支渠比降≥支渠沿線地面比降，則控制點位于支渠尾部，反之位于支渠首部；若斗渠比降≥斗渠沿線地面比降，則控制點位于斗渠尾部，反之位于斗渠首部；若農(nóng)渠比降≥農(nóng)渠沿線地面比降，則控制點位于農(nóng)渠尾部，反之位于農(nóng)渠首部，最終確定控制點位置。5.3推算典型支渠渠首設(shè)計水位各級渠道入口處的水位是根據(jù)灌溉面積上控制點的高程加各種水頭損失，自下而上逐級推算出來的。水位公式如下:水里通過渠系建筑物的水頭損失如表5-1所示。表5-1渠道建筑物水頭損失最小數(shù)值表渠別控制面積（萬畝）進水閘節(jié)制閘渡槽倒虹吸公路橋干渠10～400.1～0.20.10.150.40.05支渠1～60.1～0.20.070.070.30.03斗渠0.3～0.40.05～0.150.050.050.20農(nóng)渠0.05取第四支渠為典型支渠。1.支渠：，；>，取支渠首為控制點。2.斗渠：，，；<。取斗渠渠尾為控制點。3.農(nóng)渠：，；>，取農(nóng)渠渠首為控制點。4.計算支渠渠首設(shè)計水位5.4推算干渠設(shè)計水位5.5確定引水方式根據(jù)渠首設(shè)計水位和設(shè)計年取水口水位，確定取水方式是無壩取水。

6計算渠道設(shè)計流量6.1確定工作制度干支渠續(xù)灌，斗、農(nóng)渠輪灌（各分兩組）。6.2計算典型支渠設(shè)計流量灌區(qū)總面積約為11.5萬畝，干渠長為18.005km，各支渠的長度及灌溉面積列入表6-1。表6-1支渠長度及灌溉面積渠別一支二支三支四支合計長度（km）3.9224.1834.1964.516.801灌溉面積（萬畝）1.7842.8903.2093.58011.4631.典型支渠（三支渠）及其所屬斗、農(nóng)渠的設(shè)計流量(1)計算農(nóng)渠的設(shè)計流量三支渠的田間凈流量為:因斗、農(nóng)渠分兩組輪灌，同時工作的斗渠有6條，同時工作的農(nóng)渠有4條，所以，農(nóng)渠的田間凈流量為：取田間水利用系數(shù)，農(nóng)渠的凈流量為：灌區(qū)土壤屬中粘壤土，查表得相應(yīng)的土壤透水性參數(shù)：。據(jù)此可計算農(nóng)渠每公里輸水損失系數(shù)：取農(nóng)渠的計算長度農(nóng)渠的的設(shè)計流量為：(2)計算斗渠的設(shè)計流量因一條斗渠內(nèi)同時工作的農(nóng)渠有4條，即斗渠的流量為：農(nóng)渠分兩組輪灌，各組要求斗渠供給的凈流量相等。但是，第Ⅱ輪灌組距斗渠進水口較遠，輸水損失水量較多，據(jù)此求得的斗渠毛流量較大，因此以第Ⅱ輪灌組的斗渠毛流量作為斗渠的設(shè)計流量。斗渠的工作長度為。斗渠每公里輸水損失系數(shù)為：斗渠的設(shè)計流量為：。(3)計算三支渠的設(shè)計流量斗渠也是分兩組輪灌，以第Ⅱ輪灌組要求的支渠毛流量作為支渠的設(shè)計流量。支渠的工作長度取。支渠的凈流量為：支渠每公里輸水損失系數(shù)為：支渠的設(shè)計流量為：2.計算三支渠的灌溉水利用系數(shù)：3.計算一、二支渠的設(shè)計流量(1)計算一、二、四支渠的田間凈流量(2)計算一、二、四支渠的設(shè)計流量以典型支渠（三支渠）的灌溉水利用系數(shù)作為擴大指標(biāo)，用來計算其他支渠的設(shè)計流量。6.3計算干渠設(shè)計流量(1)EF段的設(shè)計流量(2)CE段的設(shè)計流量(3)AC段的設(shè)計流量(4)OA段的設(shè)計流量5.灌區(qū)灌溉水利用系數(shù)

7渠道橫斷面設(shè)計7.1干渠各斷面設(shè)計設(shè)計過水?dāng)嗝娌捎脤嵱媒?jīng)濟斷面，取，，。擬定偏離系數(shù)。計算：。計算寬深比：。計算：。5.6.校核不沖不淤：，清水渠取0.3~0.4；；要求<<。計算結(jié)果見表7-1。表7-1干渠各