Example 2.9 EXAMPLE 2.11 A laboratory consolidation test on a normally consolidated clay showed the follow- ing results: In Example 2.9, Part (b), if the increase in Ao would have been in the manner shown in Figure 2.26, calculate the settlement of the clay layer at time t = 31.6 days after the beginning of the surcharge. Void ratio at the end of Stress, Ao' (kN/m²) consolidation, e 140 0.92 Ao 212 0.86 The specimen tested was 25.4 mm in thickness and drained on both sides. The time required for the specimen to reach 50% consolidation was 4.5 min. A similar clay layer in the field, 2.8 m thick and drained on both sides, is sub- jected to a similar increase in average effective pressure (i.e., og = 140 kN/m? and oở + Aơ' = 212 kN/m?). Determine the following. 72 kN/m2 a. The expected maximum primary consolidation settlement in the field. b. The length of time required for the total settlement in the field to reach 40 mm. t = 15 days Time, t FIGURE 2.26 Ramp loading (Assume a uniform initial increase in excess pore water pressure with depth.)

Example 2.9 EXAMPLE 2.11 A laboratory consolidation test on a normally consolidated clay showed the follow- ing results: In Example 2.9, Part (b), if the increase in Ao would have been in the manner shown in Figure 2.26, calculate the settlement of the clay layer at time t = 31.6 days after the beginning of the surcharge. Void ratio at the end of Stress, Ao' (kN/m²) consolidation, e 140 0.92 Ao 212 0.86 The specimen tested was 25.4 mm in thickness and drained on both sides. The time required for the specimen to reach 50% consolidation was 4.5 min. A similar clay layer in the field, 2.8 m thick and drained on both sides, is sub- jected to a similar increase in average effective pressure (i.e., og = 140 kN/m? and oở + Aơ' = 212 kN/m?). Determine the following. 72 kN/m2 a. The expected maximum primary consolidation settlement in the field. b. The length of time required for the total settlement in the field to reach 40 mm. t = 15 days Time, t FIGURE 2.26 Ramp loading (Assume a uniform initial increase in excess pore water pressure with depth.)

Principles of Geotechnical Engineering (MindTap Course List)

9th Edition

ISBN:9781305970939

Author:Braja M. Das, Khaled Sobhan

Publisher:Braja M. Das, Khaled Sobhan

Chapter11: Compressibility Of Soil

Section: Chapter Questions

Problem 11.9P

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