What is blast densification?

What is blast densification?

Blast densification consists on placing explosives throughout the layer requiring treatment, and then detonate them with multiple delays to generate a cyclic load. The high pressure wave breaks any interparticle bonds due to cementation and increases the pore fluid pressure.

What do you mean by liquefaction?

Liquefaction takes place when loosely packed, water-logged sediments at or near the ground surface lose their strength in response to strong ground shaking. Liquefaction occurring beneath buildings and other structures can cause major damage during earthquakes.

What are the causes of liquefaction?

Liquefaction can occur when seismic shaking agitates saturated ground material of certain types. Buildings and other surface structures supported by liquefied ground can subside or tilt over. Underground hollow structures, such as pipes and tanks, may rise to the surface due to buoyancy forces.

What is the effect of liquefaction?

Introduction. Soil liquefaction has been known to cause damage to buildings, bridges, dams, highways, pipelines, and other critical elements of infrastructure. Most liquefaction damage is associated with ground failure, i.e., permanent lateral and vertical deformations.

What is blasting in git?

Blasting is the use of buried explosives to cause the densification of loose cohesion less ground. The principal is that the blasting of explosives in a predetermined pattern causes liquefaction, followed by the expulsion of pore water and subsequent densification of the ground.

What is compaction pile?

One of a group of piles, driven in a pattern, to compact a surface layer of loose granular soil to increase its bearing capacity.

What are the types of liquefaction?

• Introduction.
• Definition of Liquefaction.
• Types of Liquefaction.
• A- Flowing liquefaction.
• B- Cyclic Softening.
• B- 1- Cyclic Liquefaction.
• B- 2- Cyclic Displacement.
• C – Surface Liquefaction.

What happens in a liquefaction zone?

In liquefaction zones, saturated sand and silt take on the characteristics of a liquid during the intense shaking of an earthquake, according to the U.S. Geological Survey. During violent quakes, seemingly solid ground can turn into the consistency of cake batter, collapsing overhead buildings and infrastructure.

How do you fix liquefaction?

The most common way of preventing the occurrence of liquefaction are foundation soil improvement methods. One type of improvement is to replace the susceptible soil with the appropriate amount of gravel. A more favourable form of the granulometric soil curve in a narrower location is obtained in this way.

What will the effects of liquefaction will be on buildings?

Liquefaction of soil causes structural instability in buildings. This occurs due to various instances of structural failure. The liquefied ground cannot sustain the stresses of its load from the foundations. Foundations will sink into the sand deposit and cause the building to lean and eventually collapse.

Who can be affected by liquefaction?

Liquefaction is one among many risk factors that builders, landlords, and insurance companies must consider when making underwriting decisions. It refers to soil instability and can be caused by various factors such as the inflow of water beneath the soil or a sudden shock caused by earthquakes or human activities.

What is Vibroflotation?

Vibroflotation is a ground improvement technique used at a considerable depth that by using a powered electrically or hydraulically probe, it strengthens the soil. The vibroflotation will compact the soil making it suitable to support design loads. The compaction of soil can be obtained in soils as deep as 200 feet.

When does liquefaction occur what happens to the sediments?

Liquefaction takes place when loosely packed, water-logged sediments at or near the ground surface lose their strength in response to strong ground shaking.

How is liquefaction a cause of an earthquake?

Liquefaction is a process by which water-saturated sediment temporarily loses strength and acts like a fluid… like when you wiggle your toes in the wet sand near the water at the beach. This effect can be caused by earthquake shaking.

How are liquefaction features used in field settings?

Liquefaction features can be used in many field settings to estimate the recurrence interval and magnitude of strong earthquakes through much of the Holocene. These features include dikes, craters, vented sand, sills, and laterally spreading landslides.

What are the different types of liquefaction units?

The units consist of alluvial fan, beach ridge, river delta topset and foreset beds, eolian dune, point bar, flood basin, natural river and alluvial fan levees,…