Bundle: Principles Of Foundation Engineering, 9th + Mindtap Engineering, 1 Term (6 Months) Printed Access Card
9th Edition
ISBN: 9781337947060
Author: Braja M. Das, Nagaratnam Sivakugan
Publisher: Cengage Learning
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Question
Chapter 10, Problem 10.6P
(a)
To determine
Find the depth of the foundation.
(b)
To determine
Find the factor of safety.
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An office building is to be supported on 150 ft : 300 ft mat foundation. The sum of the columnloads plus the weight of the mat will be 90,000 k. According to a settlement analysis conductedusing the techniques described in Chapter 8, the total settlement will be 1.8 in. The groundwatertable is at a depth of 10 ft below the bottom of the mat. Using the pseudo-coupled method,divide the mat into zones and composite each zone. Then indicate the high-end and low-endvalves of ks that should be used in the analysis.
It is proposed to build an 8 story building with a footprint
of 15 m X 20 m, resting on a mat foundation of the same
dimensions, in a saturated clay where cu = 50 kN/m²,
y = 19.0 kN/m³. Assume approximately 15 kN/m² per floor
for the live and dead loads.
a. At what depth would you place the mat to make this a
fully compensated foundation?
b. What should be the factor of safety if the mat is placed at
3.0 m depth?
It is proposed to build an 8-story building with a footprint of 20 m x 30 m, resting on a mat foundation of the same dimensions, in a saturated clay with undrained shear strength of 60 kPa. Assume approximately 12.5 kPa per floor for dead and live loads. Unit weight of soil is 18kN/m3 .
a) At what depth would you place the mat to make this a fully compensated foundation?b) What would be the depth of this mat foundation for the net factor of safety of 5?c) What is the gross factor of safety for the depth determined in the answer to question b)?
Chapter 10 Solutions
Bundle: Principles Of Foundation Engineering, 9th + Mindtap Engineering, 1 Term (6 Months) Printed Access Card
Ch. 10 - Refer to the rectangular combined footing in...Ch. 10 - Prob. 10.2PCh. 10 - Prob. 10.3PCh. 10 - Prob. 10.4PCh. 10 - Prob. 10.5PCh. 10 - Prob. 10.6PCh. 10 - Prob. 10.7PCh. 10 - Prob. 10.8PCh. 10 - A plate loading test was carried out on a medium...Ch. 10 - A 300 mm 450 mm plate was used in carrying out a...
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