Freezing method for stabilising soils - Revision history

Designing Buildings at 08:05, 11 December 2020

2020-12-11T08:05:19Z

← Older revision		Revision as of 08:05, 11 December 2020
Line 23:		Line 23:
	* Underreaming.		* Underreaming.

−	[[Category:Construction_techniques]]	+	[[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:DCN_Research,_Development_and_Innovation]] [[Category:Construction_techniques]]

Editor at 12:25, 29 November 2018

2018-11-29T12:25:08Z

← Older revision		Revision as of 12:25, 29 November 2018
Line 9:		Line 9:
	Where rapid freezing is required, liquid nitrogen is used as the freezing medium, and this can reduce the freezing time to a few days.		Where rapid freezing is required, liquid nitrogen is used as the freezing medium, and this can reduce the freezing time to a few days.

−	~~= Find out more =~~	+	= Related articles on Designing Buildings Wiki =
−		+
−	=== Related articles on Designing Buildings Wiki ===	+

	* Caisson.		* Caisson.
Line 21:		Line 19:
	* Pumps and dewatering equipment.		* Pumps and dewatering equipment.
	* Sinkholes.		* Sinkholes.
		+	* Trial pit.
	* Tunnelling.		* Tunnelling.
	* Underreaming.		* Underreaming.

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

Designing Buildings: moved Freezing method to Freezing method for stabilising soils

2018-03-12T10:11:06Z

moved Freezing method to Freezing method for stabilising soils

← Older revision

Revision as of 10:11, 12 March 2018

Editor at 16:01, 14 December 2017

2017-12-14T16:01:37Z

← Older revision		Revision as of 16:01, 14 December 2017
Line 14:		Line 14:

	* Caisson.		* Caisson.
		+	* Dewatering.
	* Excavation.		* Excavation.
	* Ground conditions.		* Ground conditions.

Editor at 12:38, 23 March 2017

2017-03-23T12:38:05Z

← Older revision		Revision as of 12:38, 23 March 2017
Line 1:		Line 1:
−	~~This describes~~ a ~~way~~ of freezing ~~groundwater or bentonite slurry so~~ to ~~form a barrier~~ that ~~then allows~~ deep earthworks to take place.	+	Freezing can be used as a method of stabilising water-saturated soils and preventing collapse next to excavations. By freezing the soil until it becomes impervious, it enables workers and plant to operate safely inside the ‘ice wall’ that is formed. In this way, deep earthworks can take place.

−	~~Pipes~~ are installed ~~in a network in~~ the ~~ground~~ to be ~~frozen, with careful placement to ensure even and equal freezing~~. ~~A refridgerant~~ is ~~then pumped into~~ and ~~through~~ the ~~pipes freezing the ground~~ to ~~about -25C~~. ~~This temperature gives adequate time should~~ the ~~plant or system otherwise become faulty~~ to ~~be repaired or a backup system started~~.	+	In order to produce the low temperatures, steel freeze pipes are installed at approximately 1 m centres around the site that is to be excavated. The pipes are comprised of two tubes. The outer tube is 100-150 mm in diameter, is sealed at the bottom and connected at the top to a return pipe. The inner tube is 38-75 mm in diameter, is open at the bottom and connected to the flow pipe at the top.

−	~~== Paris Metro Line 4 ==~~	+	These pipes carry chilled brine which is pumped down the inner tube. A refrigeration plant is used to cool the liquid, constantly re-circulating it through the pipes. The brine temperature ranges from -15 to -25-degrees, although the freezing medium must have a freezing point that is well below this temperature range, meaning that a solution of calcium chloride or magnesium chloride is often used.

−	~~This is one~~ of ~~16 lines~~ of the ~~Paris subway or MRT (Mass Rapid Transport)~~. ~~Construction started in 1905 and finished 1908 and~~ the ~~ground was frozen~~ to ~~allow~~ the ~~construction~~ of a ~~subway station~~, ~~alongside~~ the ~~sinking~~ of ~~caissons~~ to ~~allow construction of tunnels under~~ the ~~River Seine~~.	+	For the method to be employed there must be moisture content of 8% of the voids. Using a brine medium, the time to obtain a wall of ice depends on the spacing of the pipes, the refrigeration quantity and the type of soil. For example, with pipes spaced at 1 m centres, a frozen wall measuring 1 m thick in sand and gravel takes 10-12 days, and 15-17 days in clay. An observation borehole in the centre of the treated area is sunk to determine whether the frozen wall is completely continuous and excavation work can begin.

−	~~[[Category:Articles_needing_more_work]]~~ [[Category:Construction_techniques]]	+	Where rapid freezing is required, liquid nitrogen is used as the freezing medium, and this can reduce the freezing time to a few days.
		+
		+	= Find out more =
		+
		+	=== Related articles on Designing Buildings Wiki ===
		+
		+	* Caisson.
		+	* Excavation.
		+	* Ground conditions.
		+	* Groundwater control in urban areas.
		+	* Groundworks.
		+	* Pumps and dewatering equipment.
		+	* Sinkholes.
		+	* Tunnelling.
		+	* Underreaming.
		+
		+	[[Category:Construction_techniques]]

Editor: moved Freezing method (earthworks) to Freezing method

2017-03-23T12:37:22Z

moved Freezing method (earthworks) to Freezing method

← Older revision

Revision as of 12:37, 23 March 2017

Designing Buildings at 08:19, 26 January 2017

2017-01-26T08:19:10Z

← Older revision		Revision as of 08:19, 26 January 2017
Line 1:		Line 1:
−	~~= Freezing method ([https://www.designingbuildings.co.uk/wiki/Earthworks earthworks]) =~~
−
	This describes a way of freezing groundwater or bentonite slurry so to form a barrier that then allows deep earthworks to take place.		This describes a way of freezing groundwater or bentonite slurry so to form a barrier that then allows deep earthworks to take place.

	Pipes are installed in a network in the ground to be frozen, with careful placement to ensure even and equal freezing. A refridgerant is then pumped into and through the pipes freezing the ground to about -25C. This temperature gives adequate time should the plant or system otherwise become faulty to be repaired or a backup system started.		Pipes are installed in a network in the ground to be frozen, with careful placement to ensure even and equal freezing. A refridgerant is then pumped into and through the pipes freezing the ground to about -25C. This temperature gives adequate time should the plant or system otherwise become faulty to be repaired or a backup system started.
−
−

	== Paris Metro Line 4 ==		== Paris Metro Line 4 ==
Line 11:		Line 7:
	This is one of 16 lines of the Paris subway or MRT (Mass Rapid Transport). Construction started in 1905 and finished 1908 and the ground was frozen to allow the construction of a subway station, alongside the sinking of caissons to allow construction of tunnels under the River Seine.		This is one of 16 lines of the Paris subway or MRT (Mass Rapid Transport). Construction started in 1905 and finished 1908 and the ground was frozen to allow the construction of a subway station, alongside the sinking of caissons to allow construction of tunnels under the River Seine.

−	[[Category:Articles_needing_more_work]]	+	[[Category:Articles_needing_more_work]] [[Category:Construction_techniques]]

JC5: Created page with "= Freezing method ([https://www.designingbuildings.co.uk/wiki/Earthworks earthworks]) = This describes a way of freezing groundwater or bentonite slurry so to form a barrier tha..."

2017-01-25T22:38:35Z

Created page with "= Freezing method ([https://www.designingbuildings.co.uk/wiki/Earthworks earthworks]) = This describes a way of freezing groundwater or bentonite slurry so to form a barrier tha..."

New page

= Freezing method ([https://www.designingbuildings.co.uk/wiki/Earthworks earthworks]) =

This describes a way of freezing groundwater or bentonite slurry so to form a barrier that then allows deep earthworks to take place.

Pipes are installed in a network in the ground to be frozen, with careful placement to ensure even and equal freezing. A refridgerant is then pumped into and through the pipes freezing the ground to about -25C. This temperature gives adequate time should the plant or system otherwise become faulty to be repaired or a backup system started.

== Paris Metro Line 4 ==

This is one of 16 lines of the Paris subway or MRT (Mass Rapid Transport). Construction started in 1905 and finished 1908 and the ground was frozen to allow the construction of a subway station, alongside the sinking of caissons to allow construction of tunnels under the River Seine.

[[Category:Articles_needing_more_work]]