Explanation: Given Soil is cohesionless (c = 0) ϕ = 30 °, γ = 18 kN/m3 Retaining wall Height (H) = 5 m At rest earth pressure is given by (σh = ko × σv) where ko is earth pressure coefficient at rest → ko = 1 - sin ϕ = 1- sin 30° = 1 - 0.5 = 0.5 @ H = 0 m → σv = γ × H = 18 × 0 = 0 kN/m2 At rest earth pressure (σh) = 0.5 × 0 = 0 kN/m2 @ H = 5 m → σv = γ × H = 18 × 5 = 90 kN/m2 At rest earth pressure (σh) = 0.5 × 90 = 45 kN/m2 It is a linear variation Now it is asked At rest earth pressure per meter length of wall = 1/2 × H × 45 = 1/2 × 5 × 45 = 112.5 kN/m [ alt="F1 Chandramouli Ravi 15.11.2021 D1" src="//storage.googleapis.com/tb-img/production/21/11/F1_Chandramouli_Ravi_15.11.2021_D1.png" style="width: 231px; height: 244px;">