b1 = b2 = 0.6 m
q = 10 kN/m2, γ tanah = 20 kN/m2, θ tanah = 30°, c = 10
Penyelesaian:
Stabilitas terhadap guling
Menghitung Berat Dinding
Berat dinding (gunakan berat jenis, γb = 25 kN/m3)
W1 = b1 * H1 * γb = 0.6 x 2.0 x 25 x 1 m= 30 kN
W2 = 1/2 * b1 * H1 * γb =1/2 x 0.6 x 2.0 x 25 x 1 m = 15 kN
Jarak beban terhadap titik putar asumsi, o,
X1 = 1/2 * b1 + b2 = 1/2 * 0.6 + 0.6 = 0.9 m
X2 = 1/2 * b2 = 1/2 * 0.6 = 0.3 m
Momen terhadap ujung dinding penahan, o,
Mb1 = W1 * X1 = 30 x 0.9 = 27 kNm
Mb2 = W2 * X2 = 15 x 0.3 = 4.5 kNm
ΣW = 45 kN, ΣMb = 31.50 kNm
Menghitung Tekanan Tanah
Koefisien tekanan aktif (Ka)
Ka = 1 – sin θ / 1 + sin θ = 1 – sin 30 / 1 + sin 30 = 1/3
Koefisien tekanan pasif(Kp)
Kp = 1/Ka = 1 : 1/3 = 3
Tekanan tanah aktif (Pa)
Pa1 = Ka * q * H1 = 1/3 x 10 x 2 = 20/3 kN
