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Refer to Figure 18.13. Given L1 = 1.5 m, L2 = 3 m; for the sand,
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Principles of Foundation Engineering
- i need the answer quicklyarrow_forwardQuestion 3 The flownet for an excavation supported by sheet pile walls is shown in Figure Q3. The soil being excavated is a uniform fine sand with a coefficient of permeability (k) of 5×104 m/s. The width of the trench is 5 m, with a length of 50 m. A constant external water level of 2 m is maintained at the ground level. Ground level 2m 6m 6m 6m ▼ K Line of symmetry- 5m Sheet pile wall 9m (c) Determine the pore water pressure (u) at Point A. Figure Q3 (a) Explain the physical significance of a flownet. In other words, explain what these lines represent. (b) Determine the total water flow rate (Q) at the excavation floor. K (d) If the excavation was carried out on the Moon, determine the total water flow rate (Q) at the excavation floor again (assuming that the gravitational acceleration on the Moon is 1.6 m/s²).arrow_forwardQuestion 3 A new underground tunnel section is designed by a geotechnical consultant. For the underground station a 5 m wide braced excavation is made in a saturated clay as shown in Figure Q3 with unit weight, y = 18.5 kN/m², friction angle, o = 0° and cohesion, c = 20 kN/m?. The struts are spaced at 5 m center to center in plan. Refer Appendix 1 to select the sheet-pile section. i. Draw the strut forces. ii. Determine the section modulus of the sheet pile needed. Assume oall = 170 MN/m? iii. Determine the maximum moment for the wales at levels B and C. Show a complete answer, including all numerical values and necessary diagrams. 5 m 3 m B 2 marrow_forward
- 2. Design the anchored sheet pile wall supporting a loose sand fill as shown in the following Figure. GWT is at the same height on both sides, and assume yw=10kN/m³. Based on the log spiral solutions, the Ka for the loose sand is 0.3 while the Ka and Kp for the dense sand are 0.2 and 13.125, respectively. Using the free earth support method, do the following: a) For a factor of safety of 2 on the passive resistance, determine the required depth of penetration depth, D. (initial trial with D'=1.5m) b) Determine the bending moment and the anchor load. c) Select a sheet pile section from the Table 9.1 (E=210x10³ MN/m² and fair-210 MN/m²) kN/m² D 7.0m. Yt = 16.5 kN/m³ o'= 30° Loose sand fill: Yt 19.5 kN/m3 o' = = 30° Dense sand: Yt = 21 kN/m³ $' = 40° q=10 1.5m. 0.5m. Tarrow_forward6.5 The sides of an excavation 3.0m deep in sand are to be supported by a cantilever sheet pile wall. The water table is 1.5 m below the bottom of the excavation. The sand has a saturated unit weight of 20 kN/m³, a unit weight above the water table of 17 kN/m³ and the characteristic value of o' is 36°. Using the traditional method, determine the required depth of embedment of the piling below the bottom of the excavation to give a factor of safety of 2.0 with respect to passive resistance. Marrow_forwardA braced sheet pile to be used in an open cut in clay is shown in the figure. Struts are spaced longitudinally at 2.5 m center to center spacing. Unit weight of clay is 20 kN/cu.m and an unconfined compressive strength of 100 kN/m2. Determine the section modulus of wale at B if the allowable bending stress is 0.6 Fy where Fy = 248 MPaarrow_forward
- Determine the depth of embedment required for stability of the cantilever sheet pile wall shown by using the factored strength method, taking F4 = 1.3. Coarse-grained soil Ysat = 20 kN/m O's = 39" 3 m 8 = O'csarrow_forwardDetermine the factor of safety against heave on the downstream side of the single-row sheet pile structure shown in Figure 9.30. Use the following soil and design parameters: H1 = 7 m, H2 = 3 m, thickness of permeable layer (T) = 12 m, design depth of penetration of sheet pile (D) = 4.5 m, and γsat = 17 kN/m3arrow_forward1. The following is a sketch of the proposed embankment, calculate the addition of vertical stress (Bousinesq method / graph below) at the depths of points A and B. Assume the unit weight of the soil stockpile = 20 kN / m3. 2. Calculate the added vertical stress at points A and B as deep as Z = 8 m, under the rectangular loadarrow_forward
- i need the answer quicklyarrow_forwardIn Problem 14.6, assume that Dactual = 1.3 Dtheory.a. Determine the theoretical maximum moment.b. Using Rowe’s moment reduction technique, choose a sheet-pile section. Take E = 210 x 103 MN/m2 and σall = 210,000 kN/m2.arrow_forwardIn Problem 18.4, find the maximum bending moment in the sheet pile and determine the required section modulus, assuming an allowable stress of 190 MN/m2. 18.4 Refer to Figure 18.13. Given L1 = 1.5 m, L2 = 3 m; for the sand, =33, =16.5kN/m3, sat=19.0kN/m3; and, for the clay, c=50kN/m2, =0, sat=20kN/m3. Determine the depth of sheet pile required, allowing for a 50% increase from the theoretical estimate.arrow_forward
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