水利工程施工截流課程設(shè)計(jì)說明書

1、精品文檔大渡河截流課程設(shè)計(jì)說明書日期：2017年2月19日目錄1、課程設(shè)計(jì)目的32基本資料33、截流的水力計(jì)算41.1 計(jì)算步驟51.1.1 計(jì)算下游水位H下51.1.2 戧堤頂部高程的確定51.1.3 戧堤高度、頂長(zhǎng)與頂寬51.2 截流過程分析與水力計(jì)算61.3 合龍?jiān)O(shè)計(jì)流量組成81.4 圖解法84 .流態(tài)判別124.1 求水深124.2 求斷面平均流速135 截流過程的水力參數(shù)及拋投料的計(jì)算145.1 計(jì)算截流過程水力參數(shù)145.2 拋投料的計(jì)算155.3 拋投料尺寸的計(jì)算155.4 拋投量計(jì)算162 歡迎下載 。2精品文檔水利工程施工課程設(shè)計(jì)說明書1、課程設(shè)計(jì)目的課程設(shè)計(jì)的主要目的是鞏固

2、和掌握課堂所學(xué)知識(shí)，培養(yǎng)學(xué)生運(yùn)用本課程的知識(shí)解決實(shí)際問題的能力。本次課程設(shè)計(jì)的主要內(nèi)容是水利水電工程施工截流設(shè)計(jì)。2基本資料大渡河上某水電工程采用單倉戈立堵進(jìn)占，河床的剖面圖見圖1。倉戈堤處水位流量關(guān)系見表1和圖2。倉戈堤端部邊坡系數(shù)n=1.2,截流倉戈堤兩側(cè)的邊坡為1:1.5。截流材料采用當(dāng)?shù)氐闹辛：谠贫L(zhǎng)花崗巖，容重為26kN/m3。該工程壩址處天然水位流量關(guān)系見表1,施工導(dǎo)流采用左、右岸各布置一條導(dǎo)流隧洞導(dǎo)流，左、右導(dǎo)流隧洞聯(lián)合泄流的上游水位和泄流流量關(guān)系見表2和圖3。圖1河床剖面圖表1壩址處天然水位流量關(guān)系流量（m3/s）2503174105001000水位（mj）952.15952.

3、71953.48954.00955.87圖2壩址處天然水位一流量關(guān)系曲線表2上游水位一導(dǎo)流隧洞泄流量關(guān)系泄流流量（m3/s)01503004108001400上游水位（mi)953.00955.40957.03958.00960.66964.123、截流的水力計(jì)算截流設(shè)計(jì)是施工導(dǎo)流設(shè)計(jì)重要組成部分，目前我國(guó)水利水電工程截流多采用立堵截流，本次設(shè)計(jì)按立堵截流設(shè)計(jì)。其設(shè)計(jì)內(nèi)容分為：截流水力計(jì)算、截流水力分區(qū)和備料量設(shè)計(jì)。截流設(shè)計(jì)流量的確定，通常按頻率法確定，也即根據(jù)已選定的截流時(shí)段，采用該時(shí)段內(nèi)一定頻率的某種特征流量值作為設(shè)計(jì)流量。一般地，多采用截流時(shí)段10%-20%的月平均或者旬平均流量作為設(shè)計(jì)

4、標(biāo)準(zhǔn)。截流的水力計(jì)算中龍口流速的確定一般采用圖解法，截流水力計(jì)算如下。3.1 計(jì)算步驟3.1.1 計(jì)算下游水位H下截流設(shè)計(jì)流量Q。=（270+3*1）=273m3/s,計(jì)算時(shí)不考慮倉戈堤滲透流量和上游槽蓄流量。根據(jù)壩址處天然水位與流量關(guān)系曲線，由內(nèi)插法可知，H下=952.34m3.1.2 俄堤頂部高程的確定截流設(shè)計(jì)流量為273m3/s,對(duì)上游水位導(dǎo)流隧洞泄流量關(guān)系曲線使用內(nèi)插法，可得設(shè)計(jì)流量對(duì)應(yīng)水位高程為956.74m,故取倉戈基高程為957ml3.1.3 俄堤高度、頂長(zhǎng)與頂寬截流倉戈堤處河床底部高程為951ml可求得倉戈堤白設(shè)計(jì)高度為7m若取河谷兩側(cè)坡比為1:1,由河谷在高程957m處寬度為

5、46.9m,可求得倉戈堤頂部長(zhǎng)為48.9m,計(jì)算時(shí)按約為49m進(jìn)行計(jì)算，倉£堤寬度取20m通過對(duì)表3進(jìn)行表上作業(yè)，可得分流流量與上游水位關(guān)系曲線與龍口泄水曲線如圖4和圖5所示。表3水位與下泄流量跟龍口流量的關(guān)系上游水位（mm設(shè)計(jì)流量（m3/s）下泄流量（m3/s）Qd龍口流量Qg9532730.00273.00953.527331.25241.7595427362.50210.50954.527393.75179.25955273125.00148.00955.4273150.00123.00955.5273159.20113.80956273205.2167.79956.52732

6、51.2321.77956.74273273.000.00QdZ957956955954953 1952 0.0050.00100.00150.00200.00250.00300.00下泄流量（m3/s）圖4上游水位與下泄流量關(guān)系曲線Qg-Z圖5上游水位一龍口流量關(guān)系曲線3.2 截流過程分析與水力計(jì)算隨著倉戈堤進(jìn)占，河床斷面不斷束窄，上下游落差亦逐漸增大，其斷面及流態(tài)變化過程如下：1）梯形淹沒流2）梯形非淹沒流3）三角形淹沒流4）三角形非淹沒流梯形斷面與三角形斷面的分界點(diǎn)的確定：Hb=958-951=7m,即當(dāng)龍口寬度大于14m時(shí)為梯形斷面，當(dāng)龍口寬度小于14m時(shí)為三角形斷面。由龍口泄水能力計(jì)

7、算按照寬頂堰公式計(jì)算：1 -Q=mB72gH0.5式中m流量系數(shù)Z1當(dāng)上1,為淹沒流,Ho3Z1當(dāng)>-,為非淹沒流，m=0.385Ho3B龍口平均過水寬度梯形斷面：B=B-2nHBnH0三角形斷面：B=nH0Ho龍口上游水頭梯形斷面：H0=Z上一Z底三角形斷面：H0=Z上Z底(nHB0.5B，n其中：Z龍口上下游水位差Hb俄堤高度n俄堤端部邊坡系數(shù)，取n=1.0Z上一一龍口上游水位Z底一一河道底板高程/Rm由連續(xù)方程可得龍口流速計(jì)算公式為：U=2-Bh淹沒流時(shí)：h=hs式中：hs龍口底板以上的下游水深非淹沒流時(shí)：h=hc式中：hc龍口斷面的臨界水深I(lǐng)即淹沒出流時(shí)：對(duì)于梯形斷面：h=hs對(duì)

8、三角形斷面：h=hs-nHB-0.5BnII非淹沒出流時(shí)：對(duì)于梯形斷面：h=hc3.3 合龍?jiān)O(shè)計(jì)流量組成一般情況下，截流設(shè)計(jì)流量Q0由四部分組成：Q0=QQdQsQac式中，Q龍口流量；Qd-一分流量（分流建筑物中通過的流量）；Qs-倉戈堤滲透流量；Qac-上游河槽中的調(diào)蓄流量。由于不考慮倉戈堤滲透流量和上游槽蓄流量，則有：Qo=Q十Qd。聯(lián)立上述方程：即可得到龍口處水力參數(shù)變化規(guī)律。3.4 圖解法分別取定龍口寬度為B=6.5m,11.5m,16.5m,21.5m,26.5m,31.5m,36.5m,41.5m,46.5m時(shí)不同上游水位下的龍口泄流量和隧洞分流量。由截流設(shè)計(jì)流量358m3/s,

9、壩址處天然水位一流量關(guān)系曲線內(nèi)插得設(shè)計(jì)流量下的壩址處天然水位為952.34m,設(shè)計(jì)中截流設(shè)計(jì)流量為定值，故認(rèn)為下游水位不變。龍口泄流量計(jì)算結(jié)果見附錄（附表4到附表12）。表4B=46.5m流量落差計(jì)算表BZH0Z/H0mBQg46.501.340.000.00031.3080.000.51.840.270.38031.308131.3312.340.430.38531.572192.631.52.840.530.38531.972260.8223.340.600.38532.372336.812.53.840.650.38532.773420.3434.340.690.38533.173511

10、.213.54.840.720.38533.573609.3245.340.750.38533.973714.55表5B=41.5m流量落差計(jì)算表BZH0Z/H0mBQg41.501.3400.00026.6080.000.51.840.270.38026.608111.6212.340.430.38526.608162.341.53.840.390.38527.808356.6623.340.600.38526.608276.832.53.840.650.38526.608341.2734.340.690.38526.608410.053.54.840.720.38526.608482.91

11、45.340.750.38526.608559.65表6B=36.5m流量落差計(jì)算表BZH0Z/H0mBQg36.501.340.00021.310.000.51.840.270.3821.3189.3812.340.430.38521.57131.621.52.840.530.38521.97179.2423.340.600.38522.37232.772.54.840.520.38523.57427.8234.340.690.38523.17357.113.54.840.720.38523.57427.8245.340.750.38523.97504.22表7B=31.5m流量落差計(jì)算表B

12、ZH0Z/H0mBQg31.501.340.000.00016.310.000.51.840.270.38016.3168.4112.340.430.38516.57101.111.52.840.530.38516.97138.4623.340.600.38517.37180.752.53.840.650.38517.77227.959歡9下載精品文檔34.340.690.38518.17280.053.54.840.720.38518.57337.0845.340.750.38518.97399.05表8B=26.5m流量落差計(jì)算表BZH0Z/H0mBQg26.501.340.000.000

13、11.310.000.51.840.270.38011.3147.4412.340.430.38511.5770.601.52.840.530.38511.9797.6723.340.600.38512.37128.732.53.840.650.38512.77163.8234.340.690.38513.17203.003.54.840.720.38513.57246.3345.340.750.38513.97293.89表9B=21.5m流量落差計(jì)算表BZH0Z/H0mBQg21.501.340.000.0006.310.000.51.840.270.3806.3126.4612.340.

14、430.3856.5740.101.52.840.530.3856.9756.8823.340.600.3857.3776.702.53.840.650.3857.7799.6934.340.690.3858.17125.953.54.840.720.3858.57155.5945.340.750.3858.97188.72表10B=16.5m流量落差計(jì)算表BZH0Z/H0mBQg16.501.2150.000.0001.6080.0000.51.7150.290.3831.6086.11612.2150.450.3852.23312.5471.52.7150.550.3852.73720.8

15、7023.2150.620.3853.24131.8462.53.7150.670.3853.74545.70834.2150.710.3854.24962.6753.54.7150.740.3854.75382.94745.2150.770.3855.257106.717表11B=11.5m流量落差計(jì)算表BZH0Z/H0mBQg11.510.1327.5950.3850.1330.0111.50.6322.3750.3850.6370.54521.1321.7670.3851.1412.3412.51.6321.5320.3851.6455.84432.1321.4070.3852.1491

16、1.4003.52.6321.3300.3852.65319.30543.1321.2770.3853.15729.8224.53.6321.2390.3853.66143.188表12B=6.5m流量落差計(jì)算表BZH0Z/H0mBQg6.530.04862.0690.3850.0490.0013.50.5486.3830.3850.5530.38341.0483.8160.3851.0571.9344.51.5482.9060.3851.5615.126由計(jì)算結(jié)果繪制不同寬度時(shí)上游水位與龍口泄流量關(guān)系曲線和龍口泄流量如下:957.5957956.5956955.5955954.5954953

17、.5953952.5952與上游水位關(guān)系曲線，曲線交點(diǎn)即為龍口在各寬度時(shí)的上游水位和泄流量,B=46.5B=41.5B=36.5B=31.5B=26.5B=21.5B=16.5B=11.5B=6.5QZ0.00200.00400.00600.00800.00圖6:龍口流量與上游水位的關(guān)系從上圖可看出，當(dāng)倉戈堤寬度較大時(shí)，上游水位較低，龍口泄流量較大。隨著龍口寬度減小，上游水位逐漸增高，龍口泄流量逐漸減小。當(dāng)龍口寬度為0時(shí),上游來流全部經(jīng)由導(dǎo)流隧洞泄流。根據(jù)圖表數(shù)據(jù)求出各交點(diǎn)，結(jié)果見下表:龍口寬度B龍口泄流量Qd上游水位H46.5233.5953.6341.5222.3953.8136.5204

18、.8954.0931.5185.8954.426.5160.5954.821.5126.4955.3516.582.7955.8411.531956.46.54.13956.69表13不同龍口寬度下的上游水位和龍口泄流量由上表中可看出，當(dāng)龍口寬度為46.5m時(shí)，龍口泄流量小于設(shè)計(jì)流量，這是因?yàn)樵诮亓魉τ?jì)算中沒有考慮倉戈堤的滲流和上游河床的調(diào)蓄流量，實(shí)際情況應(yīng)當(dāng)是龍口寬度為0時(shí)導(dǎo)流隧洞泄流量小于設(shè)計(jì)流量358m3/s。4.流態(tài)判別4.1 求水深由表13中計(jì)算結(jié)果，判斷不同寬度下水流流態(tài)及堰流類型，并求相應(yīng)龍口斷面水深。計(jì)算表及結(jié)果見下表：表14不同寬度下的流態(tài)及水深BZH0Z/H0液態(tài)斷面類型

19、h46.51.292.630.49非淹沒流梯形1.75441.51.472.810.52非淹沒流梯形1.87436.51.753.090.57非淹沒流梯形2.06031.52.063.40.61非淹沒流梯形2.26726.52.463.80.65非淹沒流梯形2.53421.53.014.350.69非淹沒流梯形2.90116.53.54.720.74非淹沒流三角形3.96111.54.063.191.27非淹沒流三角形2.6816.54.351.403.11非淹沒流三角形1.17512 1 2下載精品文檔4.2 求斷面平均流速導(dǎo)截流工程中確定材料用料及用量時(shí)首先要計(jì)算倉戈堤龍口處的斷面流速，龍

20、口流速計(jì)算公式為：Qv=Bh式中，h為龍口計(jì)算斷面水深，根據(jù)設(shè)計(jì)截流方法、斷面類型、出流類型根據(jù)規(guī)范求得。B為過水?dāng)嗝嫫骄鶎挾?，按如下方法?jì)算。當(dāng)斷面為梯形時(shí)，B=B2nHB+nHo,H°=Z上Z堰當(dāng)斷面為三角形是，B=nH0,H0=Z上-Z堰(nHB0.5B)/nHb為倉戈堤高度(7m),n為倉戈堤端部邊坡系數(shù)(n取1.0)。(1)梯形斷面淹沒流，h=hs,由于進(jìn)占過程中，龍口底部高程不變，hs為常數(shù)。(2)梯形斷面非淹沒流，h=hhc按下式計(jì)算，二 Q2(B nhc)二3 3gB hc二1式中，n倉戈堤端部邊坡系數(shù)；a計(jì)算斷面動(dòng)能修正系數(shù)，常取a=1.0計(jì)算按上式計(jì)算hc需要進(jìn)行

21、試算。有時(shí)為了簡(jiǎn)化計(jì)算，常用矩形斷面臨界水深代替梯形斷面臨界水深，此時(shí)(3)三角形斷面淹沒流，h=hshs(4)三角形斷面非淹沒流，h=hc2aQ21hc=（一）5ng表15俄堤各寬度卜龍口流速龍口寬度B龍口泄流量cQdhBV46.5233.51.75431.8044.18741.5222.31.87426.9484.40336.5204.82.06022.1724.48331.5185.82.26717.4204.70526.5160.52.53412.7414.97221.5126.42.9018.1815.32716.582.73.9614.7534.39211.5312.6813.21

22、83.5936.54.131.1751.4102.494由上表中數(shù)據(jù)可知，龍口合攏過程中龍口流速變化先增大后減小。最大流速約為5.327m/s。5截流過程的水力參數(shù)及拋投料的計(jì)算5.1 計(jì)算截流過程水力參數(shù)根據(jù)表18中結(jié)果列表計(jì)算龍口流速、單寬流量變化過程如下表所示：表19截流過程水力參數(shù)計(jì)算表B上下游落差ZV46.51.294.18741.51.474.40336.51.754.48331.52.064.70526.52.464.97221.53.015.32716.53.54.39211.54.063.5936.54.352.494由表19中數(shù)據(jù)可繪制龍口諸水力參數(shù)變化規(guī)律如下圖:1414

23、下載精品文檔-BVBZ圖7龍口諸水力參數(shù)變化規(guī)律圖5.2 拋投料的計(jì)算拋投料計(jì)算主要為拋投塊尺寸的計(jì)算以及拋投量的計(jì)算。5.3 拋投料尺寸的計(jì)算拋投料尺寸計(jì)算采用伊茲巴公式，即V=kfg-T式中，V為水流流速，m/s；k為綜合穩(wěn)定系數(shù)；0.9g為重力加速度，m/s2;久為石塊容重，kN/m3；丁為水容重，kN/m3;d為石塊折算成球體的化引直徑，m其中v為水流流速，m/s;K為綜合穩(wěn)定系數(shù)；其中混凝土四方體取0.68-0.72，混凝土立方體取0.76-0.80，塊石取0.9;g為重力加速度，取9.8m/s2;丁i為石塊的容重，取26kN/m3；丁為水的容重，取9.8kN/m3；D為石塊折算成球體的化引直徑，m根據(jù)伊茲巴公式求得各流速下的拋投料尺寸如下表：表20各龍口寬度下拋投塊粒徑BV粒徑d46.54.1870.66841.54.4030.73936.54.4830.76631.54.7050.84326.54.9720.94221.55.3271.08116.54.3920.73511.53.5930.4926.52.4940.237圖8俄堤頂部高程寬度與塊體粒徑的關(guān)系5.3拋投量計(jì)算由水利水電工程施工組織設(shè)計(jì)手冊(cè)第一卷542頁，由上表中求得的截流過程流速及相應(yīng)的拋投料