A flow net for flow around a single row of sheet piles in a permeable soil shown in Figure 8.7. Given that k, = k = k = 5 x 10-³ cm/s, determine a. How high (above the ground surface) the water will rise if piezomet placed at points a and b b. The total rate of seepage through the permeable layer per unit length c. The approximate average hydraulic gradient at c Water level Ground surface 5.6 m m H b 2.2 m Wa Fl Fl Fl

A flow net for flow around a single row of sheet piles in a permeable soil shown in Figure 8.7. Given that k, = k = k = 5 x 10-³ cm/s, determine a. How high (above the ground surface) the water will rise if piezomet placed at points a and b b. The total rate of seepage through the permeable layer per unit length c. The approximate average hydraulic gradient at c Water level Ground surface 5.6 m m H b 2.2 m Wa Fl Fl Fl

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

6. Two observation wells have been constructed in the confined aquifer shown below. If the flow rate (Q) is 0.01 m³/hr/unit width, Porosity, n= 0.26, effective porosity=0.23 and and compressibility of aquifer matrix is a = 10-8 ms2/kg: compressibility of water, B = 45.8 x10 11N/m² i. ii. lii. 20 m K₁-15 miday 300m K₂-7 K₁-10 m/day Determine K2 what is the effective hydraulic conductivity (K) for the system Calculate transmissivity and Storativity
4. With two cases shown in the following figure: Plot pore pressure with depth for the soils if hydraulic conductivity of soils K1 = 5 x K2. a- b- flow through a unit thickness of the cross-section if K1 = 5 x 10$ (f/s) and K2 = 1 x 10$ (f/s). Estimate the rate of seepage (q) per linear foot of cross-section, i.e. calculate the rate of C- Plot flow net for 2 cases. -z (ft) z (ft) Water Water 3 ft 3 ft Soil 1 1.5 ft Soll 1 Sol 2 3 ft 3 ft 3 ft 1.5 ft Soil 2 Datum psf Datum psf porous stone porous stone 3 ft 1.5 ft 1.5 ft Case 1 Case 2
Take note: Answer and write your solution on a clean paper clearly. During a flood flow the depth of water in a 12 m wide rectangular channel was found to be 3.5 m and 3.3 m at two sections 300 m apart. The drop in the water-surface elevation was found to be 0.18 m. Assuming Manning’s coefficient to be 0.023, determine the following: a. Average value of k? b. Estimate the flood discharge through the channel ?
3. A 500-m long levee made of compacted clay impounds water in a reservoir as shown in Figure 3. A sandy-silt seam of average thickness 1.0 m (measured in the direction in the vertical direction) cuts across the otherwise impermeable clay. The average hydraulic conductivity of the sandy-silt seam is 1.5 x105 cm/sec. Determine the volume of water that flows into the ditch every day. EL. 38 m Levee Reservoir (Compacted day) EL: 32 m EL: 30 m Sand seam EL: 26m DitchEL: 24m Clay 50 m (Not to scale) Figure 3
A falling head hydraulic conductivity test is performed on a sample of soil. The stand pipe having a diameter of 0.20cm is observed and it takes 60 seconds for the water to drop by 50 cm from an initial hydraulic head of 90cm. The sample has a length of 20cm, and a diameter of 4cm. a.Find the coefficient of permeability (cm/sec) b.Solve for the hydraulic gradient c. Compute the rate of flow of water in the soil. (cm' /sec.) 0.20 cm 6 s TAND PIPE 50cm Acm 不 20am -: SOIL
In order to compute the seepage loss through the foundation of a cofferdam, flownets were constructed. The result of the flownet study gave Nf = 6, Nd = 16. The head lost during seepage was 19.68 ft. If the hydraulic conductivity of the soil is k = 13.12 x 10-5 ft/min, compute the seepage loss per foot length of the dam per day. a.1.9 ft3/day/foot length of the dam b.1.95 ft3/day/foot length of the dam c.1.39 ft3/day/foot length of the dam d.2.9 ft3/day/foot length of the dam e.2.25 ft3/day/foot length of the dam
E Problem 3. Given the following set up, where the reservoir levels are maintained at a constant levation: Find the total head for points A and B Find the hydraulic gradient for the system What is the pressure head at C? (in other words, if we install a piezometer at C, how high would the water level rise?) If 1.5 cm of water flows through the soil in 2 min, what is the hydraulic conductivity for the soil? A=10 cm? 6cm 9cm 4cm SOIL- ---- DATUM 10cm
A dam, shown in Figure 5 retains IO m of water. A sheet pile wall (cutoff curtain) on theupstream side, which is used to reduce seepage under the dam, penetrates 7 m into a 20 mthick silty sand stratum. Below the silty sand is a thick deposit of clay. The averagecoefficient of permeability of the silty sand is 2.0 x 10-4 cm/sec. Assume that the siltysand is homogeneous and isotropic.(i) Draw the flow net under the dam.(ii) Calculate the seepage rate, q per meter length of the sheet pile.
4: For the soil profile shown in Fig. (3), a steady vertical flow occurring. Having the effective vertical stress at point (A) = 52 kPa, find: (answer 4 only). a) Total head and pressure head at points (A, B, C). b) Rate of flow in (m³/hr.m²). c) Discharge velocity and seepage velocity for soils 1 and 2. V=Vj d) Value and direction of seepage force on a soil mass of 0.1 m³ volume at mid-depth of soil (1). e) Factor of safety against boiling. Fig.3 E 3m w 9 C. B Soil-1 k = 1.0 m/sec Y sat = 18.0 kN/m³ e = 1.2 Soil-2 k = 0.5 m/sec Ysat = 20.0 kN/m³ 6₁52² e=0.6 Datum ¥ W.T.L G.S.L Piezometer
Refer to the figure. If H1 = 1.94 m, H2 = 2.37 m, h = 1.c m, e =0.49, Gs = 2.67,area of the tank = 0.64 m2, and hydraulic conductivity of the sand (k) = 0.3d cm/sec. What is the upward seepage force per unit volume of soil?
1. For a constant head laboratory permeability test on a fine sand, the following values are given: L = 300 mm; D₁ = 200 mm; h = 400 mm; Vol = 420 m³; t = 4 min; e = 0.55. a. Compute the coefficient of permeability in cm/sec. b. Compute the discharge velocity in cm/sec. c. Compute the velocity. seepage 2. For a falling head permeability test, the following are given. Length of specimen is 380 mm, are of specimen - 6.5 cm², hydraulic conductivity of soil specimen is 0.175 cm/min. a. What should be the area of the stand pipe for the head to drop from 650 cm to 300 cm in 8 min?
Soil layers are shown as the right figure. Given: H₁ = 2 m, k₁ = 10-4 cm/sec H₂ = 3 m, K₂ = 3.2 x 10-² cm/sec H₂ = 4 m, K₂ = 4.1 x 10-5 cm/sec Estimate the ratio of horizontal equivalent hydraulic conductivity and vertical equivalent hydraulic conductivity, i.e., k./k₂ T * H₂ H₂ a. 152 Ob. 270 O c. 140 O d. 225 k₁ k₂ k3