A pile group with a design load of 200 tons is to be used to support the individual column footings in a modern building. However, it is known that the load may on rare occasions reach as high as 300 tons. Civil engineering consultants have used previous experience with similar pile foundations, supplemented with soil tests, to generate an estimate of 0.75 for the probability of a pile group being able to support the 300-ton load. They have calculated, further, that of the 25% of the piles that will not support the 300-ton load, 50% will fail under a load of 270 tons or less, while 70% will fail under a load of 285 tons or less. However, the safety case for the building requires that the probability be greater than 0.9 that a pile group can carry the extreme load of 300 tons. The civil engineer in charge may order just one proof test, which may be at either 270 or 285 tons. He would prefer the test with the lower load, as it is less difficult and cheaper to administer.

A pile group with a design load of 200 tons is to be used to support the individual column footings in a modern building. However, it is known that the load may on rare occasions reach as high as 300 tons. Civil engineering consultants have used previous experience with similar pile foundations, supplemented with soil tests, to generate an estimate of 0.75 for the probability of a pile group being able to support the 300-ton load. They have calculated, further, that of the 25% of the piles that will not support the 300-ton load, 50% will fail under a load of 270 tons or less, while 70% will fail under a load of 285 tons or less. However, the safety case for the building requires that the probability be greater than 0.9 that a pile group can carry the extreme load of 300 tons. The civil engineer in charge may order just one proof test, which may be at either 270 or 285 tons. He would prefer the test with the lower load, as it is less difficult and cheaper to administer.

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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Similar questions

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