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Lateral Earth Pressure and Retaining Walls. Vertical or near-vertical slopes of soil are supported by retaining walls, cantilever sheet-pile walls, sheet-pile bulkheads, braced cuts and other similar structures.
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Vertical or near-vertical slopes of soil are supported by retaining walls, cantilever sheet-pile walls, sheet-pile bulkheads, braced cuts and other similar structures. dr. isamjardaneh / foundation engineering 61303 / 2010
Vertical or near-vertical slopes of soil are supported by retaining walls, cantilever sheet-pile walls, sheet-pile bulkheads, braced cuts and other similar structures. dr. isam jardaneh / foundation engineering 61303 / 2010
Vertical or near-vertical slopes of soil are supported by retaining walls, cantilever sheet-pile walls, sheet-pile bulkheads, braced cuts and other similar structures. dr. isam jardaneh / foundation engineering 61303 / 2010
Lateral Earth Pressures dr. isam jardaneh / foundation engineering 61303 / 2010
Tie rod Anchor Sheet pile Lateral Support In geotechnical engineering, it is often necessary to prevent lateral soil movements. Braced excavation Anchored sheet pile Cantilever retaining wall dr. isamjardaneh / foundation engineering 61303 / 2010
Lateral Support We have to estimate the lateral soil pressures acting on these structures, to be able to design them. Soil nailing Gravity Retaining wall Reinforced earth wall dr. isam jardaneh / foundation engineering 61303 / 2010
Sheet Pile Sheet pile wall dr. isam jardaneh / foundation engineering 61303 / 2010
Soil Nailing dr. isam jardaneh / foundation engineering 61303 / 2010
Lateral Support Reinforced earth walls are increasingly becoming popular. dr. isam jardaneh / foundation engineering 61303 / 2010
The proper design of those structures requires an estimation of lateral earth pressure. Lateral earth pressure is a function of several factors, such as: The type and amount of wall movement The shear strength parameters of the soil The unit weight of the soil The drainage conditions in the backfill dr. isam jardaneh / foundation engineering 61303 / 2010
Nature of Lateral Earth Pressure dr. isam jardaneh / foundation engineering 61303 / 2010
Passive At Rest Active dr. isam jardaneh / foundation engineering 61303 / 2010
Lateral Earth Pressure Lateral earth pressure is a function of effective vertical stress dr. isam jardaneh / foundation engineering 61303 / 2010
Ơh=kƠv K=coefficient of lateral earth pressure
Lateral earth pressure is a function of effective vertical stress Lateral Earth Pressure at Rest dr. isam jardaneh / foundation engineering 61303 / 2010
Water Table dr. isam jardaneh / foundation engineering 61303 / 2010
q γ1 H1 γ2 H2 γwH2 γ1H1 γ1H1 q γ2H2 K0 K0 K0 K0
Ko = 1 - sinφ for NCC Ko = 0.95 - sinφ for NCC Ko = 0.4 + 0.007 (PI) for 0 > PI > 40 Ko = 0.46 + 0.001 (PI) for 40 > PI > 80 Ko = 0.19+0.233log(PI)
Active Lateral Earth Pressure Wall moves away from the soil
William John MacquornRankine 1820 – 1872 Scottish civil engineer, physicist and mathematician. He was a founding contributor to the science of thermodynamics, particularly focusing on the first of the three thermodynamic laws. Rankine developed a complete theory of the steam engine and indeed of all heat engines. He was an enthusiastic amateur singer, pianist and cellist who composed his own humorous songs. He was born in Edinburgh and died in Glasgow, a bachelor. Rankine's theory, developed in 1857
Assumptions No friction between the backfill soil and retaining wall. Angle of friction(δ) = 0 Retaining wall is vertical Surface of backfill is horizontal
σ`a =Rankine Active earth pressure σ`0 = Effective vertical stress C = Cohesion Φ = Angle of internal friction Ka = Rankine active pressure coefficient Ka =(1 – sin φ)/(1+sinφ) =
Zc = depth at which pressure = zero Zc = depth of tensile cracks dr. isam jardaneh / foundation engineering 61303 / 2010
Example dr. isam jardaneh / foundation engineering 61303 / 2010
Use this dr. isam jardaneh / foundation engineering 61303 / 2010