B) ) A river bed consists of sand layer overlying impermeable rock; the depth of water is in river 2.50 m. A long cofferdam is formed by driving two lines of sheet piling at depth below the level of river bed and excavation to depth 2.m below the bed level is carried out within the coffer dam. The water level within the cofferdam is kept at excavation level by pumping. The saturated weight density of soil Ysa 20 KN/m³ , determine the factor of safety against boiling at excavation bottom. Sheet Sheet 2,0m , Dalum Rock layer

B) ) A river bed consists of sand layer overlying impermeable rock; the depth of water is in river 2.50 m. A long cofferdam is formed by driving two lines of sheet piling at depth below the level of river bed and excavation to depth 2.m below the bed level is carried out within the coffer dam. The water level within the cofferdam is kept at excavation level by pumping. The saturated weight density of soil Ysa 20 KN/m³ , determine the factor of safety against boiling at excavation bottom. Sheet Sheet 2,0m , Dalum Rock layer

Principles of Foundation Engineering (MindTap Course List)

8th Edition

ISBN:9781305081550

Author:Braja M. Das

Publisher:Braja M. Das

Chapter16: Soil Improvement And Ground Modification

Section: Chapter Questions

Problem 16.8P

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Similar questions

A river bed consists of a layer of sand 8.25 m thick overlying impermeable rock; the depth of water is 2.50 m. A long cofferdam 5.50 m wide is formed by driving two lines of sheet piling to a depth of 6.00 m below the level of the river bed and excavation to a depth of 2.00 m below bed level is carried out within the cofferdam The water level within the cofferdam is kept at excavation level by pumping. Determine the factor of safety against failure by heaving adjacent to the face of the piling.
The final flow net for the dam (Fig.) with a steel sheet pile cutoff wall located at the head-water side of the dam in order to reduce seepage loss. The dam is half a kilometer in width (shore to shore) and the permeability of the silty stratum is 3.5 x 10-4 cm/s. Find the total seepage loss under the dam in liters per year, and would the dam be more stable if the cutoff wall was placed under its tail-water side?
A clay layer of 30 m thick with a unit weight of 20 kN/m3 overlies a sand layer. The groundwater table is at the ground surface initially. A 20 m deep excavation is made in the clay layer. Piezometric measurements show artesian pressure at the bottom of the clay layer, amounting to a water level of 8 m above the excavation base. Calculate the factor of safety against the bottom heave for the excavation.
trench 80 ft long is excavated 500 ft away and is parallel to a riverbank. A sand aquifer is 40 ft thick The river water surface is 50 ft above the horizontal bottom of the aquifer. If the water depth in the trench must be maintained at 10ft, at what rate must water be pumped from the trench? How far from the trench will the aquifer cease to be saturated? Use K of sand = 30 ft/day
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Where the unconfined aquifer does typically exists?
For a sandy soil with Gs 2.68, calculate the critical hydraulic gradient that willcause boiling or quick condition for e 0.38, 0.48, 0.6, 0.7, and 0.8. Plot thevariation of icr with the void ratio.
A deposit of cohesionless soil with a permeability of 0.3 mm/s has a depth of 12 m with impervious ledge below. A sheet pile wall is driven into this deposit to a depth of 8 m. The wall extendsabove the surface of the soil, and a 3 m depth of water acts on one side. Sketch the flow net and determine the seepage quantity. a. 600 ml/s/meter length b. 300 ml/s/meter length c. 1200 ml/s/meter length d. 900 ml/s/meter length
The subgrade is 72 feet wide at the top and is 9 feet thick. It has a Specific Gravity, Gs =2.66, a final porosity of 31.0% and a degree of saturation of 86.3%. It is coming from aborrow pit with an average total unit weight of 112.6 pcf and a water content of 8.0%.How many pounds of water must be added to the borrow material for the fill? How manycubic feet of borrow must be excavated? (Hints: Draw two phase diagrams, one for theembankment and one for the borrow pit. What is common between the conditions?(Intermediate Answer, This is not a given, but a value so you can check your work as youprogress. Ww in borrow pit = 43,100,000 pounds )
A rill channel is observed at two locations during a storm, 20 and 60 m from the top of the hill. The slopes are 5 and 4 percent, the rill widths are 150 and 220 mm, and the hydraulic radii are estimated to be 01 and 0.04 m, respectively. The sediment transport rate is measured and found to be 200 and 800 kg/m-s. The rill erodibility (Kr) is estimated to be 0.004 s/m, critical shear (τc) 2.5 Pa, and transport coefficient (B) 100. Calculate the sediment transport capacity and erosion rate for each position. Show complete solution.
A masonry dam has a coefficient of permeability in the vertical and horizontal directions of kz=4m/day and kx=5m/day, respectively. The difference in the head is 18 m and the distance between the base of the dam and the downstream water surface is 18m. Assume z=35 m and width of Dam =40m Determine a) the seepage flow b) the uplift pressure (kpa)at point A C) the uplift force (Kn) acting in the dam. assume that the uplift pressure under the dam varies uniformly