The center of two columns for a framed building A and B are 3 m apart. Column A is supported by a square footing 1.25 m by 1.25 m, the base of which is 2.5 m below the groundlevel. The footing of column B is 1 m by 1 m and its base 1.5 m below ground level. The contact pressure on the clay soil under each footing is 400 kN/m². Assume the bases as point loads; 1) Find the stress increase at a depth 5 m below ground level: a) Vertically below the centres of the columns b) Midway between the columns 2) If the coefficient of compressibility of the clay layer is 0.3x102 m2/kN, estimate the differential settlement between the columns if clay is 5 m thick below column A TUTORIAL 9

The center of two columns for a framed building A and B are 3 m apart. Column A is supported by a square footing 1.25 m by 1.25 m, the base of which is 2.5 m below the groundlevel. The footing of column B is 1 m by 1 m and its base 1.5 m below ground level. The contact pressure on the clay soil under each footing is 400 kN/m². Assume the bases as point loads; 1) Find the stress increase at a depth 5 m below ground level: a) Vertically below the centres of the columns b) Midway between the columns 2) If the coefficient of compressibility of the clay layer is 0.3x102 m2/kN, estimate the differential settlement between the columns if clay is 5 m thick below column A TUTORIAL 9

Principles of Foundation Engineering (MindTap Course List)

9th Edition

ISBN:9781337705028

Author:Braja M. Das, Nagaratnam Sivakugan

Publisher:Braja M. Das, Nagaratnam Sivakugan

Chapter7: Ultimate Bearing Capacity Of Shallow Foundations: Special Cases

Section: Chapter Questions

Problem 7.6P

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