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8. Solve the following problem. You have been hired to design piles for a new hotel in Glamis CA, in preparation forthe 2021 Dune Motocross X-Games. Watch this video https://youtu.be/QIYx7GZ2jo0

to see a general overview of your site's location. The site is underlain by a 25m thick layer of dry sand. The sand is loose (has a low density; 17kN/m³), and therefore, the friction angle is low, i.e., 31 degrees. The project manager (PM) intends to use long,driven, smooth concrete piles (fc' = 4000 psi) with square cross section (width = 0.4m). Each pile will support a lateral load of 85 kN. The maximum moment in each pile must be kept under 120 kN-m and the lateral deflection must be kept under 3mm. Assume no water is present. Therefore, y is the dry unit weight (not 10 kN/m³). Prove that the pile width envisioned by the PM is unsatisfactory with respect to lateral load criteria. That is:(1) Is Mmax > 120 kN-m? and/or (2) Is yn > 3mm?а. b. Given the answer to (a) above, the PM wants to explore the possibility of improving the soil. Dynamic compaction comes to mind, given that the soil is coarse and dry. Watch the following two videos. https://youtu.be/c4rpjgi4Heo https://youtu.be/yli-pE7ugxg A dynamic compaction protocol at the site is expected to increase the unit weight to 21 kN/m3 and the friction angle to 39 degrees in the upper 5 meters. In such case, would the B = 0.4m piles be able to sustain the prescribed lateral load? That is: (1) Is Mmax < 120 kN-m? and/or (2) Is yn < 3mm?

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