A bearing wall carries a total unfactored load of 200 kN/m. It is to be supported on a 400 mm deep continuous footing. The underlying soils are medium sands with c'=0 and $' =37, and yt=19.0 kN/m3. For the dry case, ydry=17.0 kN/m3. The groundwater table is at a significant depth. After the footing with the factor of safety of 2.5 against a bearing capacity failure was built, the groundwater table rose to the ground surface. 1) Evaluate whether the footing design is still acceptable using the ASD method and the minimum safety factor of 2.5 against a bearing capacity failure. 2) If the footing fails, improve the footing design, and propose a new foundation width.

A bearing wall carries a total unfactored load of 200 kN/m. It is to be supported on a 400 mm deep continuous footing. The underlying soils are medium sands with c'=0 and $' =37, and yt=19.0 kN/m3. For the dry case, ydry=17.0 kN/m3. The groundwater table is at a significant depth. After the footing with the factor of safety of 2.5 against a bearing capacity failure was built, the groundwater table rose to the ground surface. 1) Evaluate whether the footing design is still acceptable using the ASD method and the minimum safety factor of 2.5 against a bearing capacity failure. 2) If the footing fails, improve the footing design, and propose a new foundation width.

Principles of Geotechnical Engineering (MindTap Course List)

9th Edition

ISBN:9781305970939

Author:Braja M. Das, Khaled Sobhan

Publisher:Braja M. Das, Khaled Sobhan

Chapter16: Soil Bearing Capacity For Shallow Foundations

Section: Chapter Questions

Problem 16.4P: Redo Problem 16.1 with the following: = 16.5 kN/m3, cu = 41 kN/m3, =0, Df = 1.5 m, and factor of...

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Redo Problem 16.1 with the following: = 16.5 kN/m3, cu = 41 kN/m3, =0, Df = 1.5 m, and factor of safety = 5. 16.1 A continuous footing is shown in Figure 16.17. Using Terzaghis bearing capacity factors, determine the gross allowable load per unit area (qall) that the footing can carry. Assume general shear failure. Given: = 19 kN/m3, c = 31kN/m2, =28, Df = 1.5 m, B = 2 m, and factor of safety = 3.5. Figure 16.17
Redo Problem 16.1 with the following: = 115 lb/ft3, c = 1100 lb/ft2, =35, Df = 3.5 ft, B = 5 ft, and factor of safety = 4. 16.1 A continuous footing is shown in Figure 16.17. Using Terzaghis bearing capacity factors, determine the gross allowable load per unit area (qall) that the footing can carry. Assume general shear failure. Given: = 19 kN/m3, c = 31kN/m2, =28, Df = 1.5 m, B = 2 m, and factor of safety = 3.5. Figure 16.17
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