Bridge scour - Revision history

Editor at 16:58, 3 November 2021

2021-11-03T16:58:30Z

← Older revision		Revision as of 16:58, 3 November 2021
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	* Summer 2009: Seven road and foot bridges in Cumbria (due to flooding), resulting in one fatality.		* Summer 2009: Seven road and foot bridges in Cumbria (due to flooding), resulting in one fatality.

−	= Related articles on Designing Buildings ~~Wiki~~ =	+	= Related articles on Designing Buildings =

	* Abutments.		* Abutments.

Designing Buildings at 09:44, 10 February 2021

2021-02-10T09:44:42Z

← Older revision		Revision as of 09:44, 10 February 2021
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	* Underwater foundations.		* Underwater foundations.

−	[[Category:~~Definitions~~]] [[Category:~~DCN_Definition~~]] [[Category:International]] [[Category:Health_and_safety_/_CDM]] [[Category:Construction_techniques]]	+	[[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:Definitions]] [[Category:International]] [[Category:Health_and_safety_/_CDM]] [[Category:Construction_techniques]]

Editor at 08:10, 4 June 2020

2020-06-04T08:10:54Z

← Older revision		Revision as of 08:10, 4 June 2020
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	There have been many laboratory experiments devoted to establishing equations that can calculate scour. Piers and abutments are central to some of the studies, along with types of sediment, water flow rates and so on.		There have been many laboratory experiments devoted to establishing equations that can calculate scour. Piers and abutments are central to some of the studies, along with types of sediment, water flow rates and so on.

−	Work by hydrologists and hydraulic technicians in this area is important, since it can determine the viability of a bridge placed in certain locations. On site inspections record river flow and other geological details~~. If the elevation of the site is likely to change significantly, then the placement is not suitable unless regular maintenance can be performed~~.	+	Work by hydrologists and hydraulic technicians in this area is important, since it can determine the viability of a bridge placed in certain locations. On site inspections record river flow and other geological details.

	For existing structures, measurements are gathered and bridges are ranked based on their scour risk. This may result in the creation of a scour plan of action that includes monitors or sensors along with precautions to take if the safety of the bridge becomes compromised.		For existing structures, measurements are gathered and bridges are ranked based on their scour risk. This may result in the creation of a scour plan of action that includes monitors or sensors along with precautions to take if the safety of the bridge becomes compromised.
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	* Underwater foundations.		* Underwater foundations.

−	[[Category:Definitions]] [[Category:International]] [[Category:Health_and_safety_/_CDM]] [[Category:Construction_techniques]]	+	[[Category:Definitions]] [[Category:DCN_Definition]] [[Category:International]] [[Category:Health_and_safety_/_CDM]] [[Category:Construction_techniques]]

Designing Buildings at 06:19, 4 June 2020

2020-06-04T06:19:58Z

← Older revision		Revision as of 06:19, 4 June 2020
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	= Bridge collapses associated with scour =		= Bridge collapses associated with scour =

−	Bridge scour is an ongoing issue and a major cause of bridge failure. In the United States it is estimated that more than half of ~~the accidents of this type~~ are caused (at least partially) by scour. It is the most common cause of highway bridge failure in the country.	+	Bridge scour is an ongoing issue and a major cause of bridge failure. In the United States it is estimated that more than half of bridge failures are caused (at least partially) by scour. It is the most common cause of highway bridge failure in the country.

	In the United Kingdom, catastrophic bridge collapses are relatively uncommon. However, since the 1840s, scour related structural failures have been linked to approximately 15 deaths.		In the United Kingdom, catastrophic bridge collapses are relatively uncommon. However, since the 1840s, scour related structural failures have been linked to approximately 15 deaths.

−	In October 1987, a tragic incident took place in Wales. ~~Due to scour (~~as a result of ~~recent~~ significant flooding), the Glanrhyd railway bridge ~~collapsed~~, ~~thus~~ causing ~~the~~ train to fall into the River Towy. ~~Fortunately, three~~ passengers and three crew members were able to escape, but four fatalities ~~occurred. These included~~ the train's driver and three passengers.	+	In October 1987, a tragic incident took place in Wales. Scour as a result of significant flooding resulted in the collapse of the Glanrhyd railway bridge, causing a train to fall into the River Towy. Three passengers and three crew members were able to escape, but there were four fatalities, including the train's driver and three passengers. Following this incident railway bridge inspection practises were revised.

	More recently, scour was linked to other bridge failures, including:		More recently, scour was linked to other bridge failures, including:
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	* June 2002: The Lower Ashenbottom viaduct in Lancashire (caused by torrential rain).		* June 2002: The Lower Ashenbottom viaduct in Lancashire (caused by torrential rain).
	* Summer 2009: Seven road and foot bridges in Cumbria (due to flooding), resulting in one fatality.		* Summer 2009: Seven road and foot bridges in Cumbria (due to flooding), resulting in one fatality.
−
−	~~As a result of the accident in 1987, railway bridge inspection practises have been revised.~~

	= Related articles on Designing Buildings Wiki =		= Related articles on Designing Buildings Wiki =

Designing Buildings: moved Scour to Bridge scour

2020-06-04T06:11:54Z

moved Scour to Bridge scour

← Older revision

Revision as of 06:11, 4 June 2020

Designing Buildings at 06:11, 4 June 2020

2020-06-04T06:11:26Z

← Older revision		Revision as of 06:11, 4 June 2020
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	[[File:Scourillustration.gif\|link=File:Scourillustration.gif]]		[[File:Scourillustration.gif\|link=File:Scourillustration.gif]]

−	= ~~Anticipating~~ scour ~~through calculations~~ =	+	= Predicting scour =

−	There have been many laboratory experiments devoted to establishing equations that can calculate scour. Piers and abutments ~~were~~ central to some of the studies ~~while others created models based on more complex data. Types~~ of sediment ~~were another factor in the research~~.	+	There have been many laboratory experiments devoted to establishing equations that can calculate scour. Piers and abutments are central to some of the studies, along with types of sediment, water flow rates and so on.

	Work by hydrologists and hydraulic technicians in this area is important, since it can determine the viability of a bridge placed in certain locations. On site inspections record river flow and other geological details. If the elevation of the site is likely to change significantly, then the placement is not suitable unless regular maintenance can be performed.		Work by hydrologists and hydraulic technicians in this area is important, since it can determine the viability of a bridge placed in certain locations. On site inspections record river flow and other geological details. If the elevation of the site is likely to change significantly, then the placement is not suitable unless regular maintenance can be performed.
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	= HEC-18 =		= HEC-18 =

−	In the United States, ~~the~~ Hydraulic Engineering Circular 18 (HEC-18) provides documentation that outlines best practices for the design, evaluation and inspection of bridges for scour. There are two supplementary documents ~~as well~~: Stream Stability at Highway Structures (HEC-20) and Bridge Scour and Stream Instability Countermeasures (HEC-23).	+	In the United States, Hydraulic Engineering Circular 18 (HEC-18) provides documentation that outlines best practices for the design, evaluation and inspection of bridges for scour. There are also two supplementary documents: Stream Stability at Highway Structures (HEC-20) and Bridge Scour and Stream Instability Countermeasures (HEC-23).

	Published by the Federal Highway Administration (FHWA), these manuals include additional information about estimating scour depth. However, there is some research that questions the reliability of HEC-18 due to its use of sand sediment and not other more commonly found soil materials such as compact till, stiff clay and shale.		Published by the Federal Highway Administration (FHWA), these manuals include additional information about estimating scour depth. However, there is some research that questions the reliability of HEC-18 due to its use of sand sediment and not other more commonly found soil materials such as compact till, stiff clay and shale.
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	= Preventing scour =		= Preventing scour =

−	There are several techniques to prevent (or at least reduce) the occurrence of scour. ~~These include the following:~~	+	There are several techniques to prevent (or at least reduce) the occurrence of scour.

	== Riprap (shot rock, rock armor or rubble) ==		== Riprap (shot rock, rock armor or rubble) ==

−	This term describes large stones, concrete blocks or even construction debris placed by engineers on shorelines that are adjacent to bridges. It is the most common form of scour remediation, although it is not deemed entirely reliable by the Federal Highway Administration under HEC-18 and 23.	+	This term describes large stones, concrete blocks or even construction debris placed by engineers on shorelines that are adjacent to bridges. This is the most common form of scour remediation, although it is not deemed entirely reliable by the Federal Highway Administration under HEC-18 and 23.

	[[File:Riprap.jpg\|link=File:Riprap.jpg]]		[[File:Riprap.jpg\|link=File:Riprap.jpg]]

Editor at 18:30, 3 June 2020

2020-06-03T18:30:18Z

← Older revision		Revision as of 18:30, 3 June 2020
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	* Braced frame.		* Braced frame.
	* Bridge construction.		* Bridge construction.
		+	* Bridge structures.
	* Caissons.		* Caissons.
	* Civil engineer.		* Civil engineer.
	* Counterweights.		* Counterweights.
		+	* On the road to ruin - How America's infrastructure is failing.
	* Piers.		* Piers.
	* Pile foundations.		* Pile foundations.
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	* Underwater foundations.		* Underwater foundations.

−	[[Category:Definitions]] [[Category:~~Health_and_safety_/_CDM~~]] [[Category:~~Regulations~~]] [[Category:~~Standards_/_measurements~~]]	+	[[Category:Definitions]] [[Category:International]] [[Category:Health_and_safety_/_CDM]] [[Category:Construction_techniques]]

Editor at 18:11, 3 June 2020

2020-06-03T18:11:37Z

← Older revision		Revision as of 18:11, 3 June 2020
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	= HEC-18 =		= HEC-18 =

−	Hydraulic Engineering Circular 18 (HEC-18) provides documentation that outlines best practices for the design, evaluation and inspection of bridges for scour. There are two supplementary documents as well: Stream Stability at Highway Structures (HEC-20) and Bridge Scour and Stream Instability Countermeasures (HEC-23).	+	In the United States, the Hydraulic Engineering Circular 18 (HEC-18) provides documentation that outlines best practices for the design, evaluation and inspection of bridges for scour. There are two supplementary documents as well: Stream Stability at Highway Structures (HEC-20) and Bridge Scour and Stream Instability Countermeasures (HEC-23).

	Published by the Federal Highway Administration (FHWA), these manuals include additional information about estimating scour depth. However, there is some research that questions the reliability of HEC-18 due to its use of sand sediment and not other more commonly found soil materials such as compact till, stiff clay and shale.		Published by the Federal Highway Administration (FHWA), these manuals include additional information about estimating scour depth. However, there is some research that questions the reliability of HEC-18 due to its use of sand sediment and not other more commonly found soil materials such as compact till, stiff clay and shale.
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	== Riprap (shot rock, rock armor or rubble) ==		== Riprap (shot rock, rock armor or rubble) ==

−	This term describes large stones, concrete blocks or even construction debris placed by engineers on shorelines that are adjacent to bridges. It is the most common form of scour remediation, although it is not deemed entirely reliable By the Federal Highway Administration under HEC-18 and 23.	+	This term describes large stones, concrete blocks or even construction debris placed by engineers on shorelines that are adjacent to bridges. It is the most common form of scour remediation, although it is not deemed entirely reliable by the Federal Highway Administration under HEC-18 and 23.

	[[File:Riprap.jpg\|link=File:Riprap.jpg]]		[[File:Riprap.jpg\|link=File:Riprap.jpg]]

Editor at 17:58, 3 June 2020

2020-06-03T17:58:24Z

← Older revision		Revision as of 17:58, 3 June 2020
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	* Railway engineering.		* Railway engineering.
	* River engineering.		* River engineering.
−	* Road joints.
	* Structural engineer.		* Structural engineer.
	* Underwater foundations.		* Underwater foundations.

	[[Category:Definitions]] [[Category:Health_and_safety_/_CDM]] [[Category:Regulations]] [[Category:Standards_/_measurements]]		[[Category:Definitions]] [[Category:Health_and_safety_/_CDM]] [[Category:Regulations]] [[Category:Standards_/_measurements]]

Editor at 17:57, 3 June 2020

2020-06-03T17:57:49Z

← Older revision		Revision as of 17:57, 3 June 2020
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	* Road joints.		* Road joints.
	* Structural engineer.		* Structural engineer.
		+	* Underwater foundations.

	[[Category:Definitions]] [[Category:Health_and_safety_/_CDM]] [[Category:Regulations]] [[Category:Standards_/_measurements]]		[[Category:Definitions]] [[Category:Health_and_safety_/_CDM]] [[Category:Regulations]] [[Category:Standards_/_measurements]]