A 1.5 mx 1.5 m footing is carrying a 400 kN load as shown in the figure below. Depth (m) 0.0 1.0 2.0 3.5 Df 6.0 77 Groundwater Sandy table soil (Yw9.81 kN/m³): Stiff Clay (OCR = 2) Bedrock Yt 16.5 kN/m³ E = 9,000 kPa Ysat 17.5 kN/m³. E 15,000 kPa Ysat 18.0 kN/m³ eo= 0.8 Cc = 0.15, C₁ = 0.02 Eu = 40,000 kPa (a) Estimate the immediate settlement beneath the center of the footing. Assuming that Poisson's ratios of sand and soft clay are 0.3 and 0.5, respectively. Use numerical integration approach. For the calculations, use layers (below the bottom of the footing) of thicknesses: 1 m; 1.5 m, and 2.5 m. (b) Determine the primary consolidation settlement beneath the center of the footing. Note: Use the 2:1 method to determine the stress increase below the footing.

A 1.5 mx 1.5 m footing is carrying a 400 kN load as shown in the figure below. Depth (m) 0.0 1.0 2.0 3.5 Df 6.0 77 Groundwater Sandy table soil (Yw9.81 kN/m³): Stiff Clay (OCR = 2) Bedrock Yt 16.5 kN/m³ E = 9,000 kPa Ysat 17.5 kN/m³. E 15,000 kPa Ysat 18.0 kN/m³ eo= 0.8 Cc = 0.15, C₁ = 0.02 Eu = 40,000 kPa (a) Estimate the immediate settlement beneath the center of the footing. Assuming that Poisson's ratios of sand and soft clay are 0.3 and 0.5, respectively. Use numerical integration approach. For the calculations, use layers (below the bottom of the footing) of thicknesses: 1 m; 1.5 m, and 2.5 m. (b) Determine the primary consolidation settlement beneath the center of the footing. Note: Use the 2:1 method to determine the stress increase below the footing.

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

The following picture depicts a soil profile that has two sources of above-ground loading: (1) a point load of 650 kN and (2) a rectangular footing that support a loading of 900 kN. Calculate the following: Vertical effective stress (σ’v ) at point A. Assume free field condition (i.e., no effect from the above-ground point load and rectangular footing). Horizontal total stress (σh ) at point A. Assume free field condition. Vertical effective stress (σ’v ) at point B. Assume free field condition. Vertical effective stress (σ’v ) at point C. Consider the effect from the point load only. Vertical effective stress (σ’v ) at point D. Consider the effect from the rectangular footing only. Use the DM 7.01 method. Approximate method is not allowed. Vertical effective stress (σ’v ) at point E. Consider the effect from the rectangular footing only. Use the DM 7.01 method. Approximate method is not allowed. Vertical effective stress (σ’v ) at point E. Consider the effects from the…
|!;9 ELABORATE Try solving the following problem: Practice Problem: The following are the results of a consolidation test on a sample soil: a. Plot the e-log o' curve b. Using Casagrande's method, determine the preconsolidation pressure. c. Calculate the compression index, Cc e 1.1 1.085 1.055 1.01 0.94 0.79 0.63 Pressure, o' (ton /ft²) 0.25 0.50 1.00 2.00 4.00 8.00 16.00
Find the settlement due to consolidation of a 9ft × 9ft coloumn foundation (figure) with a load of 1500 Ibs. The foundation is placed at 3 ft below the top surface and the clay layer is 25 ft thick. There is a sand layer underneath of the clay layer. The density of the clay layer is 115 Ibs/cf the compression index of the clay layer is 0.32 and the initial void ratio of the clay is 0.085. Assume that the pressure is distributed at a 2:1 ratio and clay is normally consolidated.
Question 1) For a shallow foundation measuring (1.7 m x 2.2 m) as shown below: , C. Estimate the primary consolidation settlement; when the bottom sandy layer is replacing with a 5 m thickness of a clay layer. Noting that, the propertiės of the clay are the same for the bottom sandy soil. Use yw=10 kN/m³ qnet= 1.2 MN/m2 G.S 1.5 m Sand Ya=16 kN/m³ Ysat= 17 kN/m3 %3D 2.5 m N60=52 V W.T. Silty Sand Yd=18 kN/m³ Ysat = 18.5 kN/m? N60=52 3.5 m Sand Ya=19 kN/m3 Ysat = 22 kN/m³ e, = 0.4, Ae=0.04 , o'= 194 kN/m2 5 m Cc= 0.3, Cs= 0.2 , Ca= 0.05 N60=60 CS Scanned with CamScanner
2- Determine the stress increase below the center of the footing using both theoretical and approximate methods at the top, middle and bottom of the clay layer. In addition, determine the average stress increase for the clay layer. Dimensions in Heights in m Unit weights in kN/m3 kN m P2 H1 H2 H3 BL Hw 2.5 Yoati 18.0 19.0 3.0 3.0 2.0 16.0 2 3 1174 Load - 0 Hw H1 H2 H3 OSand Clay (hoemally conactiduted)
Calculate the settlement of the 10-ft-thick clay layer that will result from the load carried by a 5-ft-square footing. The clay is normally consolidated. Use the 2:1 method to calculate the average increase of effective pressure in the clay layer. 10 ft 10 ft 10 ft 5 ft ↓ Dry sand Footing size 5 ft x 5ft Sand Clay Ydry = 100 pcf Groundwater table Ysat = 120 pcf Ysat = 110 pcf % = 1.0 LL=40
A 5-ft fill is to be placed over the following soil profile shown below. Determine if the clay is normally consolidated or over-consolidated. The pre-consolidation pressure (past maximum consolidation stress) of the clay is 1000 lb/ft3. 5 ft 2 ft 4 ft Proposed Fill, y = 120 lb/ft³ Sand Clay Rock 2 ft A Ydry = 100 lb/ft³ Ground water table Ysat 110 lb/ft³ = o'= Pc = 1000 lb/ft²
The figure below shows a proposed foundation site, with 10 ft of sand overlying 20 ft of clay with consolidation properties shown. The clay is normally consolidated. Assume 1-D conditions.a. Compute the initial σ′v at the middle of the clay layer prior to excavation and constructionb. After excavation and during construction, the foundation area will be heavily loaded with the structure and equipment so that σ′v at the middle of the clay layer will be increased to 3900 psf. Determine the settlement that will occur under these conditionsc. After construction is completed, the equipment will be removed and the final σ′v at the middle of the clay layer will be 3200 psf. Compute the swell that occurs after the equipment is removed
Q#4: Plate load test performed on a uniform deposit of sand and the following observations were recorded. The size of the plate was 45cm x 45cm. Plot the Pressure-Settlement Curve and determine the safe load on a footing 2m x 2m if the settlement is not to exceed 40mm. Pressure (kPa) 2 4 8 12 16 24 Settlement (mm) 3 6 20 40 60 100 Note: Write the proper answer in word format Subject: Geotechnical Design
The soil profile at a road construction site is as shown in figure (not to scale). A large embankment is to be constructed at the site. The ground water table (GWT) is located at the surface of the clay layers, and the capillary rise in the sandy soil is negligible. The effective stress at the middle of the clay layer after the application of the embankment loading is 180 kN/m². Take unit weight of water, Yw = 9.81 kN/m3. Embankment load boudi Sand GWT 2m y = 18.5 kN° it enit Clay Specific gravity, G̟ = 2.65 Water content, w = 45% Compession index, C. = 0.25 6m %3D %3D Impermeable layer The primary consolidation settlement (in m, round off to two decimal places) of the clay layer resulting from this loading will be
A 650-kN column load is supported on a 1.5 m wide by 2.0 m long by 0.5 m deep spread foot-ing. The soil below is a well-graded, normally consolidated sand with g = 18.0 kN/m3 and the following SPT N60 values:Depth (m) 1.0 2.0 3.0 4.0 5.0N60 12 13 13 8 22 The groundwater table is at a depth of 25 m. Compute settlement of the footing using the gen-eralized elastic method with Christian and Carrier’s (1978) influence factors.
2. A 2m X 2m footing carrying 1400KN load is constructed in a site with 2.5m thick clay layer under a 2.5m thick sand layer. If the footing and the ground water table are located at 1.5m below the surface, calculate the consolidation settlement of the footing. You may assume the following soil properties: for sand sat 15.7kN/m°, and for clay eo= 0.65, Cc = 0.25, Cs = 0.06, O'p = 200kN/m² and sat =19.25KN/m³. 19.25kN/m and t = %3D