Question

In: Civil Engineering

What is liquefaction of sand? how can it prevented

What is liquefaction of sand? how can it prevented

Solutions

Expert Solution

Loose saturated sand deposits can lose a part or whole of their Shear strength when subjected to a sudden shock or other dynamic loading.Shear strength of Sand is given by

where

= effective stress at depth z

If the Sand deposit is shaken by an earthquake or other dynamic loads. extra pore pressure(u) is developed and shear strength equation becomes

If

Therefore the phenomenon when the shear strength of sand becomes zero or negligible due to dynamic loads is called liquefaction of sand.Sand flows like a liquid and structures resting on such sands sink or excessively settle.

Liquefaction can be prevented by

1. Vibroflotation of Sand : Compacting loose sand deposit by inserting probes deep into soil to reduce air voids

2. Stabilizing materials injected into the soil

3 Electro - osmosis: Electrodes placed beneath structures to reduce pore pressure during earthquake.

4. Compaction piles

5. Replacing the sandy soil with a cohesive soil which does not liquefy during earthquake

6. Placing Sand or gravel drains in the soil to help dissipate extra pore pressure quickly during earthquakes.


Related Solutions

2- What are risk factors for Child abuse and how can they be prevented?
2- What are risk factors for Child abuse and how can they be prevented?
Can aliasing be prevented? If so, give one example of how.
Can aliasing be prevented? If so, give one example of how.
How can alcohol withdrawal be predicted and prevented? How can a restless, combative patient be managed?...
How can alcohol withdrawal be predicted and prevented? How can a restless, combative patient be managed? What is the therapeutic effect of lorazepam? Identify resources that should be offered to this patient suffering from alcohol withdrawl to support his recovery.
Analyze how climate changes affects on natural disasters and suggest how we can prevented?
Analyze how climate changes affects on natural disasters and suggest how we can prevented?
Discuss the general post-operative complications following surgery and show how they can be prevented.
Discuss the general post-operative complications following surgery and show how they can be prevented.
Discuss what series of events may lead to septicemia and how it should be prevented and...
Discuss what series of events may lead to septicemia and how it should be prevented and treated.
How could the Fall of Enron have been prevented and what are ethical concerns as to...
How could the Fall of Enron have been prevented and what are ethical concerns as to why it happened?
whata are the types of fraud? How are fraud prevented
whata are the types of fraud? How are fraud prevented
Is budgetary slack a desirable feature? Can it be prevented? Why or why not?
Is budgetary slack a desirable feature? Can it be prevented? Why or why not?
know how net protein catabolism can be prevented when a client has chronic kidney disease .
know how net protein catabolism can be prevented when a client has chronic kidney disease .
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT