Subsoil improvements - Revision history

Editor at 19:27, 5 March 2021

2021-03-05T19:27:16Z

← Older revision		Revision as of 19:27, 5 March 2021
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	BTEC National Construction - Pearson		BTEC National Construction - Pearson

−	[[Category:Construction_techniques]] [[Category:Design]]	+	[[Category:DCN_Guidance]] [[Category:Construction_techniques]] [[Category:Design]]

Designing Buildings at 12:31, 26 March 2020

2020-03-26T12:31:30Z

← Older revision		Revision as of 12:31, 26 March 2020
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	Geotextiles are permeable fabrics that can be used to filter, reinforce, separate, drain or protect. They work by allowing filtration or separation of granular layers in-ground applications. They are commonly used in construction and are a relatively easy way to improve soil characteristics.		Geotextiles are permeable fabrics that can be used to filter, reinforce, separate, drain or protect. They work by allowing filtration or separation of granular layers in-ground applications. They are commonly used in construction and are a relatively easy way to improve soil characteristics.
		+
		+	For more information see: Geotextiles.

	= Related articles on Designing Buildings Wiki =		= Related articles on Designing Buildings Wiki =
Line 50:		Line 52:
	* Alluvium.		* Alluvium.
	* Bearing capacity.		* Bearing capacity.
		+	* Geotextiles.
	* Groundwater.		* Groundwater.
	* Grouting.		* Grouting.
Line 56:		Line 59:
	* Soil compaction.		* Soil compaction.
	* Soil survey.		* Soil survey.
−	* Substrate.
	* The importance of soil analysis.		* The importance of soil analysis.
−	* Topsoil.
	* Types of soil.		* Types of soil.
	* Vibro-compaction for ground improvement.		* Vibro-compaction for ground improvement.

Designing Buildings at 12:29, 26 March 2020

2020-03-26T12:29:44Z

← Older revision		Revision as of 12:29, 26 March 2020
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	* To increase its bearing capacity by improving the shear strength.		* To increase its bearing capacity by improving the shear strength.
−	* ~~Enhance~~ the soil stiffness and density so that liquification can be avoided.	+	* To enhance the soil stiffness and density so that liquification can be avoided.
−	* To prevent excessive settlement ~~especially~~ in the construction of roads ~~and~~ runways ~~etc~~.	+	* To prevent excessive settlement, in particular in the construction of roads, runways and so on.
	* To stabilise or immobilise contaminants within the soil.		* To stabilise or immobilise contaminants within the soil.

−	Some ~~techniques~~ available are:	+	Some of the available techniques are described below.

−	* Land drainage.	+	= Land drainage =
−	* Grouting.	+
−	* Vibroflotation.	+
−	* Compaction with rollers.	+
−	* Dynamic compaction.	+
−	* High energy impact compaction.	+
−	* Vacuum consolidation.	+
−	* Geotextiles.	+
−		+
−	~~= Land Drainage~~ =	+

−	The purpose of this method is to lower a high-water table and to dry out the ground to improve its bearing capacity. The technique might involve water entering into a flexible perforated drainage pipe in the ground and directed away. A layer of shingle might be added ~~as an additional help~~.	+	The purpose of this method is to lower a high-water table and to dry out the ground to improve its bearing capacity. The technique might involve water entering into a flexible perforated drainage pipe in the ground and being directed away. A layer of shingle might be added to assist.

	= Grouting =		= Grouting =

−	Soft subsoil is a serious problem for maritime construction. A solution can be to a cement-based mixture into the subsoil under pressure. The mixture will expand and fill any voids and eventually form a strengthened base ~~and improve~~ the permeability.	+	Soft subsoil is a serious problem for maritime construction. A solution can be to inject a cement-based mixture into the subsoil under pressure. The mixture will expand and fill any voids and eventually form a strengthened base with improved the permeability.
		+
		+	For more information see: Grouting.

	= Vibroflotation =		= Vibroflotation =

−	A vibrating probe is lowered into the ground by a vibrating jets causing vibration. After the probing process is complete a granular hardcore mixture is poured into the hole and further compacted by the probe. Once the probe is slowly removed ~~again~~, further hardcore is pushed in until a column is formed. This process requires specialist plant and cranes.	+	A vibrating probe is lowered into the ground by vibrating jets causing vibration. After the probing process is complete a granular hardcore mixture is poured into the hole and further compacted by the probe. Once the probe is slowly removed, further hardcore is pushed in until a column is formed. This process requires specialist plant and cranes.

	= Compaction with rollers =		= Compaction with rollers =

	Plant rolling machinery is used to compact soil.		Plant rolling machinery is used to compact soil.
		+
		+	For more information see: Roller

	= Dynamic compaction =		= Dynamic compaction =

−	A method that is used to increase the density of soil deposits. The process uses specialist plant and cranes ~~that drops~~ a ~~heavyweight~~ repeatedly on the ground at consistent intervals.	+	A method that is used to increase the density of soil deposits. The process uses specialist plant and cranes to drop a heavy weight repeatedly on the ground at consistent intervals.

	= High energy impact compaction =		= High energy impact compaction =
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	= Geotextiles =		= Geotextiles =

−	Geotextiles are permeable ~~nonwoven~~ fabrics that can be used to filter, reinforce, separate, drain or protect. ~~It works~~ by allowing filtration or separation of granular layers in-ground applications. ~~It is~~ commonly used in construction and a relatively ~~easier application~~ to improve soil characteristics.	+	Geotextiles are permeable fabrics that can be used to filter, reinforce, separate, drain or protect. They work by allowing filtration or separation of granular layers in-ground applications. They are commonly used in construction and are a relatively easy way to improve soil characteristics.

	= Related articles on Designing Buildings Wiki =		= Related articles on Designing Buildings Wiki =
Line 55:		Line 50:
	* Alluvium.		* Alluvium.
	* Bearing capacity.		* Bearing capacity.
−	* Clay.
−	* Excavation.
−	* Geophysical survey.
	* Groundwater.		* Groundwater.
−	* ~~Ground heave~~.	+	* Grouting.
	* Insitu testing of soils.		* Insitu testing of soils.
		+	* Roller.
		+	* Soil compaction.
	* Soil survey.		* Soil survey.
	* Substrate.		* Substrate.
Line 66:		Line 60:
	* Topsoil.		* Topsoil.
	* Types of soil.		* Types of soil.
		+	* Vibro-compaction for ground improvement.
	* Water table.		* Water table.
−	* What does in situ mean?

	= External references =		= External references =

Editor2: Created page with "= Introduction = Many techniques are available to improve subsoil. The aim of soil improvements can be: * To increase its bearing capacity by improving the shear strength. * En..."

2020-03-23T11:54:37Z

Created page with "= Introduction = Many techniques are available to improve subsoil. The aim of soil improvements can be: * To increase its bearing capacity by improving the shear strength. * En..."

New page

= Introduction =

Many techniques are available to improve subsoil. The aim of soil improvements can be:

* To increase its bearing capacity by improving the shear strength.
* Enhance the soil stiffness and density so that liquification can be avoided.
* To prevent excessive settlement especially in the construction of roads and runways etc.
* To stabilise or immobilise contaminants within the soil.

Some techniques available are:

* Land drainage.
* Grouting.
* Vibroflotation.
* Compaction with rollers.
* Dynamic compaction.
* High energy impact compaction.
* Vacuum consolidation.
* Geotextiles.

= Land Drainage =

The purpose of this method is to lower a high-water table and to dry out the ground to improve its bearing capacity. The technique might involve water entering into a flexible perforated drainage pipe in the ground and directed away. A layer of shingle might be added as an additional help.

= Grouting =

Soft subsoil is a serious problem for maritime construction. A solution can be to a cement-based mixture into the subsoil under pressure. The mixture will expand and fill any voids and eventually form a strengthened base and improve the permeability.

= Vibroflotation =

A vibrating probe is lowered into the ground by a vibrating jets causing vibration. After the probing process is complete a granular hardcore mixture is poured into the hole and further compacted by the probe. Once the probe is slowly removed again, further hardcore is pushed in until a column is formed. This process requires specialist plant and cranes.

= Compaction with rollers =

Plant rolling machinery is used to compact soil.

= Dynamic compaction =

A method that is used to increase the density of soil deposits. The process uses specialist plant and cranes that drops a heavyweight repeatedly on the ground at consistent intervals.

= High energy impact compaction =

A method that is used in low strength soils. Specialist plant is used with big hexagonal-shaped rolling attachments in a controlled dynamic drag along site.

= Vacuum consolidation =

Prefabricated vertical drains were originally used with surcharge fill to manage residual settlement in soft ground. This method was extended to include vacuum application for better results. This method uses stress transfer and surface loading techniques and is carried out by specialist contractors.

= Geotextiles =

Geotextiles are permeable nonwoven fabrics that can be used to filter, reinforce, separate, drain or protect. It works by allowing filtration or separation of granular layers in-ground applications. It is commonly used in construction and a relatively easier application to improve soil characteristics.

= Related articles on Designing Buildings Wiki =

* Alluvium.
* Bearing capacity.
* Clay.
* Excavation.
* Geophysical survey.
* Groundwater.
* Ground heave.
* Insitu testing of soils.
* Soil survey.
* Substrate.
* The importance of soil analysis.
* Topsoil.
* Types of soil.
* Water table.
* What does in situ mean?

= External references =

BTEC National Construction - Pearson

[[Category:Construction_techniques]] [[Category:Design]]