堤防渗流计算

1、堤防渗流计算（有详细的计算过程和程序）根据堤防工程设计规范GB50286-98 »附录E.2.1不透水堤基均质土堤下游无排水设备或有贴坡式排水 项目计算式数值单位备注上游坡度ml = 3 = 3 / 1:m1下游坡度m2 = 3 = 3 / 1:m2堤顶宽度B =6 = 6 m堤顶局程V顶=27 = 27 m堤底局程"底=17 = 17 m上游水位 1=24.8 = 24.8 m下游水位 2 = 18 = 18 m渗透系数 k = 1.00E-05 = 1.00E-05 m/s堤身高度H = 27-17 = 10 m上游水深 H1 = 24.8-17 = 7.8 m下游水深

2、 H2 = 18-17 = 1 mL = (27-24.8) 3+6+10 >3 = 42.6 m上有水面至下游堤脚 L = 3 78/(2 3+1) = 3.343 m m1H1/(2m1 + 1)L1 = 42.6+3.343 = 45.943 m L+ L试算法计算逸出高度h0,假设h0的试算范围h01h02,计算的步长以及精度h01 = 1 = 1 mh02 = 10 = 10 m步长=0.02 = 0.02 m精度=0.01 = 0.01 m试算得到h0 = 2.54 = 2.54 m手动输入q/k = (7.8A2-2.54A2)/(2 (45.943-3 2籽4) = 0.

3、7096 mq/k = 0.7047 = 0.7047 m平均 q/k = (0.7096+0.7047)/2 = 0.7072 m平均渗流量 q = 0.7072 0.00001 = 7.07E-06 m3/s/m浸润线方程 y=SQRT(6.4516+1.4144x)下游坝坡最大渗出坡降J = 1/3 = 0.333 / 1/m2附录E.2.2不透水堤基均质土堤下游设褥垫式排水项目计算式 数值单位备注上游坡度m1 = 3 = 3 / 1:m1下游坡度m2 = 5 = 5 / 1:m2堤顶宽度B = 6 = 6 m堤顶高程顶 =27 = 27 m堤底局程底=17 = 17 m上游水位 1 =

4、 24.8 = 24.8 m下游水位= 18 = 18 m褥垫长度Lr = 5 = 5 m 到下游堤脚渗透系数 k = 1.00E-05 = 1.00E-05 m/s堤身高度H = 27-17 = 10 m上游水深 H1 = 24.8-17 = 7.8 m下游水深 H2 = 18-17 = 1 mL = (27- 24.8) X 3+6+10X 5 -5 = 57.6 m上游水面至褥垫 L = 3X 7.8/(2 X 3+1) = 3.343 m m1H1/(2m1 + 1)L1 = 57.6+3.343 = 60.943 m L+ L逸出高度 h0 = SQRT(60.943A2+7.8A2

5、)-60.943 = 0.497 m排水体工作长度 a0 = 0.497/2 = 0.249 m h0/2q/k = 0.497 = 0.497 m h0渗流量 q = 0.497 X 0.00001 = 4.97E-06 m3/s/m浸润线方程 y=SQRT(0.247-0.994x)下游坝坡最大渗出坡降J = 1/5 = 0.2 / 1/m2附录E.2.3不透水堤基均质土堤下游设棱体排水项目计算式 数值单位备注上游坡度m1 = 3 = 3 / 1:m1下游坡度m2 = 5 = 5 / 1:m2堤顶宽度B = 6 = 6 m堤顶高程顶 =27 = 27 m上游坡度ml = 3 = 3 / 1

6、:m1上游水位 1 = 24.8 = 24.8 m下游水位= 18 = 18 m棱体顶高程=19 = 19 m到下游堤脚棱体临水坡坡率 m3 = 2 = 2 / 1:m3渗透系数 k = 1.00E-05 = 1.00E-05 m/s堤身高度H = 27-17 = 10 m棱体高度HL = 19-17 = 2 m上游水深 H1 = 24.8-17 = 7.8 m下游水深 H2 = 18-17 = 1 mL = (27- 24.8) X 3+6+10X5 -2X 5 -2X2 = 48.6 m上游水面至棱体 L = 3X 7.8/(2 X 3+1) = 3.343 m m1H1/(2m1 + 1

7、)L1 = 48.6+3.343 = 51.943 m L+ L系数 c = 1.115 = 1.115 / 与 m3有关逸出高度 h0 = 1+SQRT(1.115X 51.943)A2+(7.8-1)A2)- 1.115 X 51.943 = 1.398 mq/k = (7.8A2+1.398A2)/(2 X 51.943)= 0.604 m渗流量 q = 0.604 x 0.00001 = 6.04E-06 m3/s/m浸润线 方程 y=SQRT(1.9544-1.208x)下游坝坡最大渗出坡降J = 1/5 = 0.2 / 1/m2附录E.3.1透水堤基无排水附录E.3.1透水堤基均质

8、土堤下游无排水设备或有贴坡式排水项目计算式 数值单位备注1. 计算参数下游坡度m2 = 5 = 5 / 1:m2堤顶宽度B = 6 = 6 m堤顶高程顶 =27 = 27 m堤底局程底=17 = 17 m透水地基底局程底=7 = 7 m不透水地基顶局程上游水位 1 = 24.8 = 24.8 m下游水位= 18 = 18 m渗透系数 k = 1.00E-05 = 1.00E-05 m/s堤基渗透系数 k0 = 5.00E-05 = 5.00E-05 m/s2. 不透水堤基对应渗流量计算堤身高度H = 27-17 = 10 m上游水深 H1 = 24.8-17 = 7.8 m下游水深 H2 =

9、18-17 = 1 mL = (27- 24.8) X 3+6+10X 5 = 62.6 m上有水面至下游堤脚 L = 3X 7.8/(2 X 3+1) = 3.343 m m1H1/(2m1 + 1)L1 = 62.6+3.343 = 65.943 m L+ L试算法计算逸出高度h0,假设h0的试算范围h01h02,计算的步长以及精度h01 = 1 = 1 mh02 = 10 = 10 m步长=0.02 = 0.02 m精度=0.01 = 0.01 m试算得到h0 = 2.54 = 2.8 m程序计算q/k = (7.8A2-2.8A2)/(2 X (65.943 -5X 2.8) = 0.

10、5102 m q/k = 0.5011 = 0.5011 m平均 q/k = (0.5102+0.5011)/2 = 0.5057 m平均渗流量 qD = 0.5057 X 0.00001 = 5.06E-06 m3/s/m浸润线 方程 y=SQRT(7.84+1.0114x)下游坝坡最大渗出坡降J = 1/5 = 0.2 / 1/m23. 堤基渗流量计算透水地基厚度 T = 17-7 = 10 m堤基渗流量 q 基=0.00005 X (7.8 -1) X 10/(62.6+5 X 7.8+0.88 X 10) = 3.08E-05 m3/s/m4. 总渗流量 =0.00000506+0.0

11、000308 = 3.59E-05 m3/s/m5. 浸润线计算h01 = 1 = 1 mh02 = 10 = 10 m步长=0.001 = 0.001 m精度=0.001 = 0.001 m试算得到h0 = 2.0361 = 1.894 m程序计算q “ = 3.55212E-05 = 3.55E-05 m3/s/m浸润线方程 x=14.0766(y-1.894)+0.1408(yA2-3.5872)附录E.3.2透水堤基均质土堤下游设褥垫式排水项目计算式 数值单位备注1. 计算参数上游坡度m1 = 3 = 3 / 1:m1下游坡度m2 = 5 = 5 / 1:m2堤顶宽度B = 6 = 6

12、 m堤顶高程顶 =27 = 27 m堤底局程底=17 = 17 m透水地基底局程底 =7 = 7 m不透水地基顶局程上游水位 1 = 24.8 = 24.8 m下游水位= 18 = 18 m褥垫长度Lr = 5 = 5 m到下游堤脚渗透系数 k = 1.00E-05 = 1.00E-05 m/s堤基渗透系数 k0 = 5.00E-05 = 5.00E-05 m/s2. 不透水堤基对应渗流量计算堤身高度H = 27-17 = 10 m上游水深 H1 = 24.8-17 = 7.8 m下游水深 H2 = 18-17 = 1 mL = (27- 24.8) X 3+6+10X 5 -5 = 57.6

13、 m上游水面至褥垫 L = 3X 7.8/(2 X 3+1) = 3.343 m m1H1/(2m1 + 1)L1 = 57.6+3.343 = 60.943 m L+ L逸出高度 h0 = SQRT(60.943A2+7.8A2)-60.943 = 0.497 m排水体工作长度 a0 = 0.497/2 = 0.249 m h0/2q/k = 0.497 = 0.497 m h0渗流量 qD = 0.497 X 0.00001 = 4.97E-06 m3/s/m浸润线方程 y=SQRT(0.247-0.994x)下游坝坡最大渗出坡降J = 1/5 = 0.2 / 1/m22. 堤基渗流量计算

14、透水地基厚度 T = 17-7 = 10 m堤基渗流量 q 基=0.00 005X (7.8 -1) X 10/(57.6+5 X 7.8+0.88 X 10) = 3.23E-05 m3/s/m3. 总渗流量 =0.00000497+0.00003226 = 3.72E-05 m3/s/m4. 浸润线计算逸出高度 h0 = 0.00003723/(0.00001+0.00005/0.44) = 0.301 mq “ = 4.4223E-05 = 4.42E-05 m3/s/m浸润线 方程 x=11.3071(y-0.301)+0.1131(yA2-0.0906)附录E.4不稳定渗流计算附录E

15、.4不稳定渗流计算项目计算式 数值单位备注上游坡度m1 = 3 = 3 / 1:m1下游坡度m2 = 5 = 5 / 1:m2堤顶宽度B = 6 = 6 m堤顶高程顶 =27 = 27 m堤底局程底=17 = 17 m上游水位 1 = 24.8 = 24.8 m下游水位= 18 = 18 m土的孔隙率n = 88.00% = 88.00% /到下游堤脚土的饱和度 S顺 =50.00% = 50.00% / 到下游堤脚渗透系数 k = 1.00E-05 = 1.00E-05 m/s洪水持续时间t = 11 = 11 天950400妙土的有效 孔隙率n0 = 0.88 X (1 -0.5) = 4

16、4.00% / 到下游堤脚上游水位处堤宽 b " = 6+(27- 24.8) X (3+5) = 23.6 m上游水深 H = 24.8-17 = 7.8 m渗流在背坡出现所需时间T = 0.44 X 7.8 X (3+5+23.6/7.8)/(4 X 0.00001)= 946000 s 10.949 天洪水持续时间t = 11天 10.949 天不需计算浸润线锋面距迎水坡脚距离L浸润线锋面距迎水坡脚距离L = 2X SQRT(0.00001X 7.8 X 946000/0.44)= 25.9 m m1H1/(2m1+1)附录E.5背水坡渗流出口比降计算项目 计算式 数值单位 备

17、注1.计算参数下游坡度m2 = 5 = 5 / 1:m2堤底高程底=17 = 17 m下游水位= 18 = 18 m逸出高度 h0 = 2.54 = 2.54 m下游水深 H2 = 18-17 = 1 m2. 不透水地基逸出坡降计算2.1下游无水时渗出点 A坡降 Jo = 1/SQRT(1+5A2) = 0.196 /堤坡与不透水面交点B坡降Jo = 1/5 = 0.2 / 1/m22.2下游有水时渗出段AB内的点 计算点高程 =19 = 19 m AB 段(1819.54)内y = 19-17 = 2 / AB 段(2.541)内 渗出点 A坡降 Jo = 1/SQRT(1+5A2) = 0

18、.196 / n = 0.25 X 1/2.54 = 0.098 /在下游坡面渗出计算点坡降 J = 0.196 X (2.54 -1)/(2-1)A0.098 = 0.204 /浸没段BC内的点 适用于y/H2<0.95计算点高程 =17.7 = 17.7 m BC 段(1719.413)内y = 17.7-17 = 0.7 / BC 段(00.95)内背坡与水平面夹角a兀=atan(1/5) = 0.197 rad 11.287 度济=0.197/兀=0.063 /a0 = 1/(2 X (0.063 X (5+0.5) X SQRT(1+5A2)= 0.283 /b0 = 5/(2

19、 X (5+0.5)人2)= 0.083 /1/2 a -11/(2 X 0.063) -1 = 6.937 /计算点坡降 J = 0.283 X (0.7/1)A6.937/(1+0.083 X 1/(2.54-1) = 0.023 /3. 透水地基逸出坡降计算3.1下游无水时渗出段AB内的点计算点高程 =19 = 19 m AB 段(1719.54)内y = 19-17 = 2 / AB 段(02.54)内计算点坡降 J = 1/SQRT(1+5A2)X (2.54/2)A0.25= 0.208 /地基段BC内的点计算点与堤脚距离x = 3 = 3 m计算点坡降 J = 1/(2 X SQ

20、RT(5)X SQRT(2.54/3)= 0.206 /3.2下游有水时渗出段AB内的点计算点高程 =19 = 19 m AB 段(1819.54)内y = 19-17 = 2 / AB 段(12.54)内计算点坡降 J = 1/SQRT(1+5A2)X (2.54/2)A0.25= 0.208 /浸没坡段BC内的点计算点高程 =17.7 = 17.7 m BC 段(0.2832.823)内y = 17.7-17 = 0.7 / BC 段(02.54)内背坡与水平面夹角a兀=atan(1/5) = 0.197 rad 11.287 度a = 0.197/ 兀=0.063 /a 1 = 1/(1

21、+0.063) = 0.941 / 1/(1+ a )11 = 2.54 X 5 = 12.7 /h0X m212 = 1X5 = 5 /H2Xm2r = 0.7 X5 = 3.5 / yx m2计算点坡降J = 0.234 = 0.234 /在下游坡面渗出浸没地基面段 CD内的点计算点距堤脚距离 x = 2 = 2 m计算点坡降J = 0.108 = 0.108 /在下游坡面渗出附录E.6水位降落时均质土堤的浸润线项目 计算式 数值 单位 备注1. 计算参数上游坡度m1 = 3 = 3 / 1:m1堤底局程底=17 = 17 m堤身土料 渗透系数 k = 1.00E-05 = 1.00E-0

22、5 m/s = 0.001cm/s= 0.864m/d土体的孔隙率 n = 39.70% = 39.70% /降前水位=27 = 27 m 0.0003125m/s降后水位= 20 = 20 m 0.00023148m/s水位降落所需时间 T = 22 = 22 h = 79200 秒=0.9167 天计算上游 浸润线时间t = 15 = 15 h = 54000 秒=0.625 天2. h0(t)计算降前水深 H1 = 27-17 = 10 m VI - V底降后水深H0 = 20-17 = 3 m VO - 底降距 H = 10-3 = 7 m H1-H0水位降落的速度 V = 7/(22

23、/24) = 7.636 m/d = 0.00009m/s= 0.00212m/h百分数 a= 113.7 X (0.0001175)A(0.607A(6+log(0.001)/100= 15.03% / 公式一给水度 卬=0.1503 X 0.397 = 0.0597 /k/(卬 V) = 0.864/(0.0597 X 7.636) = 1.895 / 1/10<k/( 卬 V)<60 ,需要计算 浸润线0.31H(1/T)(k/( 卬 V)1/4 =0.31 X 7X 1/79200 X (1.895)A(1/4)= 0.0000321 /h0(t) = 7-0.000032

24、1th0(t) = 7-0.0000321 X 54000 = 5.2666 m t = 15h = 54000s3. 试算法计算t时刻渗流量q(t)和上游坡出渗点高度he(t)he(t)1 = 3+0.01 = 3.01 m H0+Stephe(t)2 = 3+5.2666 = 8.267 m H0+h0(t)步长 Step = 0.01 = 0.01 m精度=0.001 = 0.001 mL = 10X3 = 30 m H1X m1试算得到he(t) = 5.34 = 5.34 m程序计算q/k1 = (3+5.2666)人2-5.34人2)/(2 X (30 - 3X 5.34) = 1

25、.424 mq/k2 = (5.34-3)/3 X (1+ln(5.34/(5.34-3) = 1.424 m平均 q/k = (1.424+1.424)/2 = 1.424 m平均渗流量 q = 1.424 X 0.00001 = 1.42E-05 m3/s/m4.计算t时刻上游段浸润线H0+h0(t)2 = (3+5.2666)A2 = 68.3367 m22q/k = 2X 1.424 = 2.848 m浸润线方程 y=SQRT(68.3367-2.848x)附录E.7.1背水侧无限长双层堤基渗流计算和覆盖的计算附录E.7双层堤基渗流计算和覆盖的计算附录E.7.1背水侧无限长双层堤基渗流

26、计算和覆盖的计算项目计算式数值单位备注1. 计算参数上游坡度 m1 = 3 = 3 / ( 1:m1 )下游坡度 m2 = 5 = 5 / ( 1:m2 )堤顶宽度B = 6 = 6 m堤顶高程顶 =27 = 27 m堤底局程底=17 = 17 m弱透水地基底局程弱=7 = 10 m强透水地基底局程强=7 = 5 m上游水位 1 = 24.8 = 24.8 m下游水位= 18 = 18 m堤底局程底=17 = 17 m迎水侧有限长度 L = 100 = 100 m0.864m/d )=4.32m/d )604.8m/d )堤身土料 渗透系数 k = 1.00E-05 = 1.00E-05 m/

27、s (= 0.001cm/s =弱透水堤基 渗透系数 k1 = 5.00E-05 = 5.00E-05 m/s (= 0.005cm/s强透水堤基 渗透系数 k0 = 7.00E-03 = 7.00E-03 m/s (= 0.7cm/s=2. 越流系数A计算属于双层堤基）顶-底）VI-V 底）底-弱）弱-强）B+Hd< （m1+m2）=0.014 m-1k0/k1 = 0.007/0.00005 = 140 / (堤身高度 Hd = 27-17 = 10 m (上游水深 H = 24.8-17 = 7.8 m (弱透水层厚度 T1 = 17-10 = 7 m (强透水层厚度 T0 = 1

28、0-5 = 5 m (6+10X (3+5) = 86 m (SQRT(0.00005/(0.007 X 7X 5)堤底宽度b =越流系数A =3. 弱透水层CD段承压水头计算(x以下游堤脚为原点，向下游为正 ) 计算点坐标x = 10 = 10 m ( x>0 )h = 7.8 X eA( -0.014 X 10)/(1+0.014 X 86 -th(0.014 X 100) = 5.142 m4. 弱透水层CD段承压水头计算(x'以下游堤脚为原点，向上游为正 ) 计算点坐标x' = 10 = 10 m ( x' >0 )h = 7.8 X (1+0.01

29、4 X 10)/(1+0.014 X 86 -th(0.014 X 100) = 6.743 m计算简图参看规范图E.7.1附录E.7.2透水地基上弱透水层等厚有限长附录E.7双层堤基渗流计算和覆盖的计算附录E.7.2透水地基上弱透水层等厚有限长，强透水层无限长双层堤基渗流计算项目计算式数值单位备注1. 计算参数上游坡度 ml = 3 = 3 / （ 1:m1 ）下游坡度 m2 = 3 = 3 / （ 1:m2 ）堤顶宽度B = 6 = 6 m堤顶高程顶 =27 = 27 m堤底局程底=17 = 17 m弱透水地基底局程弱=7 = 10 m强透水地基底局程强=7 = 5 m上游水位 1 = 2

30、4.8 = 24.8 m下游水位= 18 = 18 m迎水侧有限长度 L1 = 30 = 30 m （弱透水地基）背水侧有限长度 L2 = 100 = 100 m （ 弱透水地基）0.864m/d )=4.32m/d )604.8m/d )弱透水堤基渗透系数k1 =强透水堤基渗透系数k0 =:5.00E-05:7.00E-03=5.00E-05 m/s (=7.00E-03 m/s (=0.005cm/s=0.7cm/s2.越流系数A计算k0/k1 = 0.007/0.00005 = 140 / ( >100弱透水层厚度 T1 = 17-10 = 7 m (强透水层厚度 T0 = 10-

31、5 = 5 m (,属于双层堤基底-弱）弱-强）)堤身高度 Hd = 27-17 = 10 m ( 顶-底)堤身土料 渗透系数 k = 1.00E-05 = 1.00E-05 m/s （= 0.001cm/s =上游水面距不透水地基H = 24.8-5 = 19.8 m ( 1- 强)堤底距不透水地基 H1 =:17-5 = 12 m (=底-强=T1+T0 )弱透水层底距不透水地基H0 = 10-5 = 5 m (弱-强）堤底宽度 b = 6+10X (3+3) = 66 m (B+Hd< (m1+m2)越流系数 A = SQRT(0.00005/(0.007 X 7X 5)= 0.0

32、14 m-1A(0.441T0) =0.014 X 0.441 X5 = 0.031 / ( <1，公式适用)d' 1/0.014 x arth(0.031)= 2.215 m ( = 1/Aarth(A(0.441T0)3. 试算法计算I以确定出逸段与非出逸段的分界点，假设 I的试算范围I 1I 2,计算 的步长以及精度V 1 = 0.0001 = 0 m ( = precision )匚 2 = 100 = 100 m ( = L2 )步长 STEP = 0.01 = 0.01 m精度 precision = 0.0001 = 0.0001 m试算得到 K = 64.46 =

33、 64.46 m ( 程序计算)方程左边=0.105 = 0.105 m (程序计算)方程右边=0.105 = 0.105 m (程序计算)4. 出逸段AB透水层水位计算(x以下游堤脚为原点，向下游为正)计算点坐标 x = 10 = 10 m ( 0 < x < 35.54 = L2-匚)h = 1.482 = 1.482 m5. 非出逸段BC透水层水位计算(x '以弱透水层最下游点为原点，向上游为正)计算点坐标 x' = 10 = 10 m ( 0 < x' < 64.46 = 匚)x' /T0 = 10/5 = 2 m 0 = (12

34、- 5) X 0.441 X 5/(64.46+0.441 X 5) = 0.232 m x' / A 0 = 0 = 0 m x' = 0.232 XO = 0 mh = 5+(12- 5) X (10+0.441 X 5)/(64.46+0.441 X 5) -0 = 6.282 m(x'以弱透水层最下游点为原点，向上游为正)计算点坐标 x' = 2.1 = 2.1 m ( 0 < x' < 64.46 = 匚)x' /T0 = 2.1/5 = 0.42 m 0 = (12- 5) X 0.441 X 5/(64.46+0.441

35、 X 5) = 0.232 m x' / A 0 = 0.246 = 0.246 m ( 查表 E.7.2 ) x' = 0.232 乂 0.246 = 0.057 mh = 5+(12- 5) X (2.1+0.441 X 5)/(64.46+0.441 X 5) -0.057 = 5.395 m附录E.7.2透水地基上弱透水层不等厚或不均质附录E.7双层堤基渗流计算和覆盖的计算附录E.7.2透水地基上弱透水层不等厚或不均质，强透水层无限长双层堤基渗流计算项目计算式数值单位备注1. 计算参数上游坡度 m1 = 3 = 3 / ( 1:m1 )下游坡度 m2 = 5 = 5 /

36、 ( 1:m2 )堤顶宽度B = 6 = 6 m堤顶高程顶 =27 = 27 m堤底局程底=17 = 17 m弱透水地基底局程弱 =10 = 10 m强透水地基底局程强 =7 = 7 m上游水位 1 = 24.8 = 24.8 m下游水位= 18 = 18 m弱透水层无限长强透水堤基 渗透系数 k0 = 7.00E-03 = 7.00E-03 m/s (= 0.7cm/s= 604.8m/d )2. 递推计算下游等效长度S下下游弱透水层分段数 N = 3 = 3 段(以不等厚或不均质分)2.1递推计算段次=0 = 0强透水层厚度 T0 = 10-7 = 3 m ( 弱-强)等效长度S0 = 0

37、 = 0 m ( 取0 )D0 = (1/0.022+0)/(1/0.022-0) = 1 /段次=1第 1 段渗透系数 k1 = 5.00E-05 = 5.00E-05 m/s (= 0.005cm/s = 4.32m/d )第1段厚度t1 = 5 = 5 m第1段长度L1 = 6 = 6 m越流系数 A1 = SQRT(0.00005/(0.007 X 3X 5) = 0.022 m-13 1 = 2X 0.022 X6 = 0.264 / ( 2AiLi )等效长度 S1 = 1/0.022 X (1 X eA0.264 -1)/(1 X eA0.264+1) = 5.965 mD1 =

38、 (1/0.028+5.965)/(1/0.028-5.965) = 1.401 m段次=2第 2 段渗透系数 k2 = 5.00E-05 = 5.00E-05 m/s (= 0.005cm/s = 4.32m/d )第2段厚度t2 = 3 = 3 m第2段长度L2 = 10 = 10 m越流系数 A2 = SQRT(0.00005/(0.007 X 3X 3)= 0.028 m-1 3 2 = 2X 0.028 X 10 = 0.56 / ( 2AiLi )等效长度 S2 = 1/0.028 X (1.401 x eA0.56 - 1)/(1.401 x eA0.56+1) = 15.026

39、 mD2 = (1/0.035+15.026)/(1/0.035-15.026) = 3.219 m (底-弱)段次=3第 3 段渗透系数 k3 = 5.00E-05 = 5.00E-05 m/s (= 0.005cm/s = 4.32m/d )第3段厚度t3 = 2 = 2 m第3段长度L3 = 30 = 30 m越流系数 A3 = SQRT(0.00005/(0.007 X 3X 2)= 0.035 m-13 3 = 2X 0.035 X 30 = 2.1 / ( 2AiLi )等效长度 S3 = 1/0.035 X (3.219 X eA2.1 -1)/(3.219 X eA2.1+1)

40、 = 26.477 m2.2下游等效长度 S下=26.477 = 26.477 m (即等效长度 S3 )3. 递推计算下游等效长度S上上游弱透水层分段数N = 3 = 3 段(以不等厚或不均质分 )3.1递推计算段次=0 = 0强透水层厚度 T0 = 15.026-3.219 = 11.807 m ( 弱-强)等效长度S0 = 0 = 0 m ( 取0 )D0 = (1/0.018+0)/(1/0.018-0) = 1 /段次=1第 1 段渗透系数 k1 = 5.00E-05 = 5.00E-05 m/s (= 0.005cm/s = 4.32m/d )第1段厚度t1 = 7 = 7 m第1

41、段长度L1 = 10 = 10 m越流系数 A1 = SQRT(0.00005/(0.007 X 3X 7)= 0.018 m-13 1 = 2X 0.018 X 10 = 0.36 / ( 2AiLi )等效长度 S1 = 1/0.018 X (1 x eA0.36 -1)/(1 x eA0.36+1) = 9.893 mD1 = (1/0.022+9.893)/(1/0.022-9.893) = 1.556 m段次=2第 2 段渗透系数 k2 = 5.00E-05 = 5.00E-05 m/s (= 0.005cm/s = 4.32m/d )第2段厚度t2 = 5 = 5 m第2段长度L2

42、 = 6 = 6 m越流系数 A2 = SQRT(0.00005/(0.007 X 3X 5)= 0.022 m-13 2 = 2X 0.022 X6 = 0.264 / ( 2AiLi )等效长度 S2 = 1/ 0.022 X (1.556 X eA0.264 -1)/(1.556 X eA0.264+1) = 15.413 mD2 = (1/0.028+15.413)/(1/0.028-15.413) = 2.518 m (底-弱)段次=3第 3 段渗透系数 k3 = 5.00E-05 = 5.00E-05 m/s (= 0.005cm/s = 4.32m/d )第3段厚度t3 = 3

43、= 3 m第3段长度L3 = 50 = 50 m越流系数 A3 = SQRT(0.00005/(0.007 X 3X 3) = 0.028 m-13 3 = 2X 0.028 X 50 = 2.8 / ( 2AiLi )等效长度 S3 = 1/0.028 X (2.518 X eA2.8 -1)/(2.518 X eA2.8+1) = 34.03 m3.2 上游等效长度 S上=34.03 = 34.03 m ( 即等效长度 S3 )4. 背水侧弱透水层下各点的承压水头计算(x以下游堤脚原点，向下游为正)计算点坐标x = 10 = 10 m ( x > 0 )上下游水头差 H = 24.8

44、-18 = 6.8 m堤身高度 Hd = 27-17 = 10 m ( 顶-底)堤底宽度 b = 6+10X (3+5) = 86 m ( B+Hd< (m1+m2)计算点的承压水头h = (26.477- 10) X 6.8/(34.03+86+26.477)= 0.765 m ( x = 10m )强透水层厚度 T0 = 10-7 = 3 m （ 弱-强）最后一个了，本堤防渗流计算到此结束，谢谢支持！附录E.7双层堤基渗流计算和覆盖的计算附录E.7.4递推公式计算盖重项目计算式数值单位备注1. 计算参数上游坡度 ml = 3 = 3 / ( 1:m1 )下游坡度 m2 = 5 = 5

45、 / ( 1:m2 )堤顶宽度B = 6 = 6 m堤顶高程顶 =27 = 27 m堤底局程底=17 = 17 m弱透水地基底局程弱=10 = 10 m强透水地基底局程强=7 = 7 m上游水位 1 = 24.8 = 24.8 m下游水位= 18 = 18 m弱透水层无限长强透水堤基 渗透系数 k0 = 7.00E-03 = 7.00E-03 m/s (= 0.7cm/s= 604.8m/d )2. 递推计算下游等效长度S下下游弱透水层分段数N = 3 = 3 段(以不等厚或不均质分 )2.1递推计算等效长度S0 = 0 = 0 m ( 取0 )D0 = (1/0.022+0)/(1/0.02

46、2-0) = 1 /段次=1等效总厚度tz ' = 3+0 = 3 m第1段渗透系资攵 k1 = 5.00E-05 = 5.00E-05 m/s (=0.005cm/s第1段厚度t1 = 5 = 5 m第1段长度L1 = 6 = 6 m是否有盅重 无琵盖重厚度t' = 1 = 0 m盖重渗透系数 k' = 2.00E-06 = 2.00E-06 m/s (=0.0002cm/s等效厚度t1 '=0.00005 x 0/0.000002 = 0 m等效总厚度tz越流系数A1 ='=5+0 = 5 mSQRT(0.00005/(0.007 X 3X 5)=0

47、.022 m-14.32m/d )0.1728m/d )3 1 = 2X 0.022 X6 = 0.264 / ( 2AiLi )等效长度 S1 = 1/0.02 2X (1 X 50.264 -1)/(1 X eA0.264+1) = 5.965 mD1 = (1/0.028+5.965)/(1/0.028-5.965) = 1.401 m段次=24.32m/d )第 2 段渗透系数 k2 = 5.00E-05 = 5.00E-05 m/s (= 0.005cm/s =第2段厚度t2 = 3 = 3 m第2段长度L2 = 10 = 10 m是否有盖重 无盖重盖重厚度t' = 1 =

48、0 m0.1728m/d )盖重渗透系数 k' = 2.00E-06 = 2.00E-06 m/s (= 0.0002cm/s =等效厚度 t1 ' = 0.00005 x 0/0.000002 = 0 m越流系数 A2 = SQRT(0.00005/(0.007 X 3X 3)= 0.028 m-13 2 = 2X 0.028 X 10 = 0.56 / ( 2AiLi )等效长度 S2 = 1/0.028 X (1.401 X eA0.56 - 1)/(1.401 X eA0.56+1)D2 = (1/0.016+15.026)/(1/0.016-15.026) = 1.6

49、33 m (底-段次=3第 3 段渗透系数 k3 = 5.00E-05 = 5.00E-05 m/s (= 0.005cm/s第3段厚度t3 = 2 = 2 m第3段长度L3 = 30 = 30 m是否有盖重有盖重盖重厚度t' = 1 =1m盖重渗透系数 k' = 7.00E-06 = 7.00E-06 m/s (= 0.0007cm/s等效厚度 t1 ' = 0.00005 X 1/0.000007 = 7.143 m等效总厚度 tz ' = 2+7.143 = 9.143 m越流系数 A3 = SQRT(0.00005/(0.007 X 3X 9.143)= 0.016 m-13 3 = 2X 0.016 X 30 = 0.96 / ( 2AiLi )等效长度 S3 = 1/0.016 x (1.633 x eA0.96 - 1)/(1.633 x eA0.96+1)=15.026 m)=4.32m/d )=0.6048m/d )=38.758 m2.2下游等效长度 S下=38.758 = 38.758 m （即等效长度 S3 ）3. 递推计算下游等效长度S上上游弱透水层分段数 N = 3 = 3 段（以不等厚或不均质分）3.