Two footing "A" and "B" rest in a layer of sand 2.7 m thick. The bottom of the footings are 0.90m below the ground surface. Beneath the sand layer is 1.8m day layer. Beneath the clay layer is a hard pan. The water table is at a depth of 1.8m below the ground surface. The layer of granular soil is composed of material having a saturated unit weight of 20.46 kN/m³ and a unit weight of 18.45 kN/m³. The day saturated unit weight is 16.52 kN/m³. A laboratory compression test indicates that the clay has a pre-consolidation pressure of 67 kPa. Compression index is 0.30 and the value of swell index is 0.05. Void ratio of clay is 1.50. Determine: 1. The stress increase at the center of clay layer assuming that footing “A", with a dimension 2m x 1.8m, distributes a pressure at an angle of 2 vertical to 1 horizontal. The load of the footing is 350OKN. 2. The size of the square footing “B" so that the settlement of the clay layer is the same beneath footing "A" and "B". 3. Determine the settlement beneath footing “A". A 0.9m 2mxl.8m = 18.45KN/m³3 1,8m 2.7m GRANULAR SOIL GWT 2.7m Ysat = 20.46kN /m Ysat = 16.52kN/m³ o: = 67kPa Cc = 0.30 C5 = 0.05 1.8m CLAY LAYER e = 1.50

Two footing "A" and "B" rest in a layer of sand 2.7 m thick. The bottom of the footings are 0.90m below the ground surface. Beneath the sand layer is 1.8m day layer. Beneath the clay layer is a hard pan. The water table is at a depth of 1.8m below the ground surface. The layer of granular soil is composed of material having a saturated unit weight of 20.46 kN/m³ and a unit weight of 18.45 kN/m³. The day saturated unit weight is 16.52 kN/m³. A laboratory compression test indicates that the clay has a pre-consolidation pressure of 67 kPa. Compression index is 0.30 and the value of swell index is 0.05. Void ratio of clay is 1.50. Determine: 1. The stress increase at the center of clay layer assuming that footing “A", with a dimension 2m x 1.8m, distributes a pressure at an angle of 2 vertical to 1 horizontal. The load of the footing is 350OKN. 2. The size of the square footing “B" so that the settlement of the clay layer is the same beneath footing "A" and "B". 3. Determine the settlement beneath footing “A". A 0.9m 2mxl.8m = 18.45KN/m³3 1,8m 2.7m GRANULAR SOIL GWT 2.7m Ysat = 20.46kN /m Ysat = 16.52kN/m³ o: = 67kPa Cc = 0.30 C5 = 0.05 1.8m CLAY LAYER e = 1.50

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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