A certain column carries a vertical downward load of 1350 KN. It is to be supported on a 1.0 m deep, square footing. The soil beneath this footing has the following properties: y = 20.8 kN/m², c'=4.7 kPa, p=31°. The groundwater table is at a depth of 1.5 m below the ground surface. Using ASD, compute the footing width required for a factor of safety of 3.5 using Terzaghi's method. Solution: 1. Determination of the method: According to the given information, the best suitable method would be Tergaghi's mehod. 2. Determination of bearing capacity factors - function of o': a. Ne = b. Nq = Na c. Ny = 3. Determination of other bearing capacity factors: (B stards for the width of the footing) Surcharge stress at depth D: D = Effect of GWT on submerged unit weight: y'= 4. Calculate ultimate bearing pressre using the Tergaghi's method: Ultimate bearing pressure qult = B kPa; Allowable bearing pressure qa = Bearing pressure due to loading q = 5. Figure out the width B by setting q≤ qa: Calculated width B = For construction, use B = m; m; kPa; + + B kPa; /B kPa; /B² kPa;

A certain column carries a vertical downward load of 1350 KN. It is to be supported on a 1.0 m deep, square footing. The soil beneath this footing has the following properties: y = 20.8 kN/m², c'=4.7 kPa, p=31°. The groundwater table is at a depth of 1.5 m below the ground surface. Using ASD, compute the footing width required for a factor of safety of 3.5 using Terzaghi's method. Solution: 1. Determination of the method: According to the given information, the best suitable method would be Tergaghi's mehod. 2. Determination of bearing capacity factors - function of o': a. Ne = b. Nq = Na c. Ny = 3. Determination of other bearing capacity factors: (B stards for the width of the footing) Surcharge stress at depth D: D = Effect of GWT on submerged unit weight: y'= 4. Calculate ultimate bearing pressre using the Tergaghi's method: Ultimate bearing pressure qult = B kPa; Allowable bearing pressure qa = Bearing pressure due to loading q = 5. Figure out the width B by setting q≤ qa: Calculated width B = For construction, use B = m; m; kPa; + + B kPa; /B kPa; /B² kPa;

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

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