Analisis Koefisien Rembesan pada Saluran Irigasi Tersier di Desa Sei Beras Sekata Daerah Irigasi Medan Krio Kecamatan Sunggal Kabupaten Deli Serdang

(1)

Lampiran 1.Flow Chart penelitian

Mulai

Diukur debit air

Dihitung efisiensi penyaluran air

Dihitung luas penampang saluran

Dihitung nilai parameter

Dibandingkan nilai koefisien rembesan antara literatur dan pengamatan dilapangan

(2)

Lampiran 6. Perhitungan kerapatan massa, kerapatan partikel dan porositas.

Tepi Kanan Saluran I 231,02 192,33 80 1,28 2,34 50,77

Tepi Kiri Saluran I 211,67 192,33 80 1,19 2,19 58,68

Dalam Saluran I 260,2 192,33 100 1,10 2,88 49,77

Tepi Kanan Saluran II 228,77 192,33 100 1,20 2,65 49,06

Tepi Kiri Saluran II 245,79 192,33 105 1,35 2,33 48,72

Dalam Saluran II 256,5 192,33 110 1,33 2,60 42,92

BTKO = Berat tanah kering oven (massa tanah kering) Volume total = volume ring sample

Volume Total = πd t

= cm 5 cm = ( cm )

= 192,33 cm3 Saluran 1

(3)

=

⁄

= 1,19 g/cm3 Bagian Dalam Saluran

Ms = 211,67 g

ρb=

=

⁄

= 1,10 g/cm3 Kerapatan Partikel Tepi Kanan Saluran

Berat Tanah = 245,79 g Volume Tanah = l Volume Air = 200 ml Volume Air Tanah = 305 ml

ρs =

Volume Ruang Por I = (volume air + volume tanah)- volume air tanah Volume Ruang Pori = (200ml+ 260 ml) – 305 ml

= 155 ml

ρs =

=

2,34 g/cm3 Tepi Kiri Saluran

Berat Tanah = 228,77 g

(4)

Volume Air = 200 ml Volume Air Tanah = 304 ml

ρs =

Volume Ruang Pori = (volume air + volume tanah)- volume air tanah Volume Ruang Pori = (200 ml+ 250 ml) – 304 ml

= 146 ml

ρs =

=

2,19 g/cm3 Bagian Dalam Saluran

Berat Tanah = 231,02 g

Volume Tanah = 240 ml

Volume Air = 200 ml

Volume Air Tanah = 280 ml

ρs =

Volume Ruang Pori = (volume air + volume tanah)- volume air tanah Volume Ruang Pori = (200 ml+ 240 ml) – 280 ml

= 160 ml

ρs =

=

2,88 g/cm3 Porositas

Tepi Kanan Saluran Porositas = (1

-

(5)

= (1- ⁄

(6)

=

⁄

= 1,35 g/cm3

Bagian Dalam Saluran

Ms = 256,15 g

ρb =

=

⁄

= 1,33 g/cm3 Kerapatan Partikel

Tepi Kanan Saluran

ρs =

Volume Ruang Pori = (volume air + volume tanah)- volume air tanah Volume Ruang Pori = (200ml+ 230 ml) – 280 ml

= 150 ml

ρs =

=

2,65 g/cm3 Tepi Kiri Saluran

(7)

Volume Tanah = l Volume Air = 200 ml Volume Air Tanah = 310 ml

ρs =

Volume Ruang Pori = (volume air + volume tanah)- volume air tanah Volume Ruang Pori = (200ml+ 250 ml) – 310 ml

= 140 ml

ρs =

=

2,33 g/cm3

ρs =

Volume Ruang Pori = (volume air + volume tanah)- volume air tanah Volume Ruang Pori = (200ml+ 230 ml) – 281ml

= 150 ml

ρs =

(8)

Tepi Kiri Saluran

Porositas = (1

-

) x 100%

= (1- ⁄

⁄ ) x 100% = 54,72%

Tepi Kanan Saluran

Porositas = (1-

) x 100%

= (1- ⁄

⁄ ) x 100% = 42,06%

Porositas = (1-

) x 100%

= (1- ⁄

(9)

Lampiran 7. Perhitungan debit saluran 1 dan saluran 2 Perhitungan debit pada saluran 1dan saluran 2

No Lokasi Saluran 1(L/det) Saluran 2 (L/det)

(10)

(11)

Hilir

Cara Tampung

Ulangan Waktu (t)

(det)

Volume (v) (l)

Debit (Q) (l/det)

I 2,24 5,19 2,317

II 2,69 5,58 2,074

III 3,19 6,27 1,966

Q

Rata-rata

=

⁄ ⁄ ⁄

= 2,119 ⁄ Sekat Ukur Thompson

H = 7,5cm Q = 0,0138 H5/2 = 0,0138 (7,5 cm)5/2 = 2,13 l/det

Ukuran Saluran Tersier Saluran 1

Kedalaman = = 15,5 cm

= 0,16 m

Lebar = = 128,67 cm

(12)

Saluran 2

Kedalaman = = 16,73 cm = 0,17 m Lebar =

= 80,67 cm = 0,806 m

Lampiran 8. Perhitungan kehilangan air

Lokasi Kehilangan Air

(l/det)

Saluran 1 0,631

Saluran 2 0,867

Kehilangan air Saluran 1

Kehilangan Air = Qhulu-Qhilir = (2,420 – 1,789)l/det = 0,631 l/det

= 0,631 x 10-3 m3/det Saluran 2

Kehilangan Air = Qhulu - Qhilir = (2,993 – 2,126)l/det = 0,867 l/det

(13)

Lampiran 9. Perhitungan evapotranspirasi Saluran 1

Kc Rumput = 0,85

Tempertur (t) = 27,31oC Lama Penyinaran Matahari (P) = 4,15 Kt = 0,0311t + 0,240

= 0,0311 (27,31 oC) + 0,240 = 1,09

K = kt x kc K = 1,09 x 0,85

= 0,927

U =

U

=

= 79,289 mm/bln = 2,64 mm/hari Saluran 2

Kc Jagung Umur 1,5 bulan = 0,96

Kc Rumput = 0,85

Tempertur (t) = 27,31oC Lama Penyinaran Matahari (P) = 4,15 Kc =

(14)

= 0,91

Kt = 0,0311t + 0,240

= 0,0311 (27,31 oC) + 0,240 = 1,09

K = kt x kc K = 1,09 x 0,91

= 0,99

U =

U

=

= 784,69 mm/bulan = 2,82 mm/hari

Lampiran 10. Perhitungan perkolasi Saluran 1

Ulangan Perkolasi (mm/hari)

I 13,67

II 12

III 8,67

Rata-rata 11,45

Ulangan I

- P1 (Perkolasi di titik 0 m) h1 = 13,5 cm

h2 = 12,4 cm P1 =

(15)

(16)

(17)

= 12 mm/hari

Perkolasi Rata-rata Ulangan II =

= = 12 mm/hari

Ulangan III

h2 = 10,5 cm P1 =

mm/hari

P1 =

P1 = 1cm/hari = 10 mm/hari

- P2 (Perkolasi di titik 15m) h1 = 10 cm

h2 = 9,2 cm P2 =

mm/hari

P2 =

P2 = 0,8 cm/hari = 8 mm/hari

(18)

h2 = 9,5 cm P3 =

mm/hari

P3 =

Perkolasi Rata-rata Ulangan III =

= = 8,67 mm/hari Maka,

Nilai Rata-rata Perkolasi Saluran I = = 11,45 mm/hari

Saluran 2

Ulangan Perkolasi (mm/hari)

I 6

II 6,67

III 6,33

Rata-rata 6,33

Ulangan I

h2 = 11 cm P1 =

(19)

(20)

(21)

Perkolasi Rata-rata Ulangan II =

= = 6,67 mm/hari Ulangan III

h2 = 9,5 cm P1 =

mm/hari

P1 =

P1 = 0,8cm/hari = 8 mm/hari

- P2 (Perkolasi di titik 15m) h1 = 10,6 cm

h2 = 10 cm P2 =

mm/hari

P2 =

(22)

P3 =

Lampiran 11. Koefisien rembesan N

o Lokasi Koefisien Rembesan (mm/hari)

1 Tepi Kanan Saluran

Perkolasi = 11,45 mm/hari x luas saluran = ⁄

(23)

Evapotranspirasi = 2,64 mm/hari x luas saluran = ⁄

= 1,18 x 10-6 m3/det = 1,18 x 10-3 L/det

Debit Rembesan = Kehilangan air – (Perkolasi + Evapotranspirasi) = 0,631 x 10-3 m3/det – (1,18 x 10-3 + 5,12 x 10-3)m3/det = 0,625 x 10-3 m3/det

= 0,625 L/det

q2 =

=

d kanan = 35 cm

= 0,35 m

d kiri = 105 cm

= 1,05 m

h1 = 37,6 cm

= 0,376 m

Tepi Kanan =

=

⁄

(24)

= 1,03 x 10-4 m/detik = 8.899,2 mm/hari

Tepi Kanan =

=

⁄

= 3,09 x 10-4 m/detik = 26.697,6 mm/hari

Saluran 2

Perkolasi = 6,33 mm/hari x luas saluran = ⁄

= 1,77 x 10-6 m3/det = 1,77 x 10-3 L/det

Evapotranspirasi = 2,82 mm/hari x luas saluran = ⁄

= 7,90 x 10-7 m3/det = 7,90 x 10-4 L/det

Debit Rembesan = Kehilangan air – (Perkolasi + Evapotranspirasi) = 0,867 x 10-3 m3/det – (1,77 x 10-6+ 7,90 x 10-7)m3/det = 8,64 x 10-4m3/det

= 0,864 L/det

q2 =

=

(25)

=

d kanan = 95 cm

= 0,95 m

d kiri = 28 cm

= 0,28 m

h1 = 24,5 cm

= 0,245 m

Tepi Kanan

=

⁄

= 9,12 x 10-4 m/detik = 78.796,8 mm/hari

Tepi Kiri =

=

⁄

= 2,69 x 10-4 m/detik = 23.241,6 mm/hari Lampiran 12.Perhitungan efisiensi saluran

No Lokasi Jarak Pengukuran Efisiensi (%)

1 Saluran 1 30 m 73,93

Saluran 2 30 m 71,03

Saluran 1

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W =

=

x 100% W = 73,93%

Saluran 2

Qhulu = 2,13L/det Qhilir = 2,99L/det W =

=