Arch Variations - Revision history

DT Online at 08:01, 30 June 2017

2017-06-30T08:01:02Z

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	[[Category:Bridges]]		[[Category:Bridges]]
			[[Category:Bridges and Beams]]
	[[Category:The Victorians]]		[[Category:The Victorians]]

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	[[Category:Bridges]]		[[Category:Bridges]]
			[[Category:The Victorians]]

DT Online at 10:12, 1 March 2017

2017-03-01T10:12:40Z

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	=====Roman Arch=====		=====Roman Arch=====
	[[File:Alcantara.JPG\|250px\|right\|Roman arch at Alcantara, Spain\|link=~~https~~://en.wikipedia.org/wiki/Alc%C3%A1ntara_Bridge]]		[[File:Alcantara.JPG\|250px\|right\|Roman arch at Alcantara, Spain\|link=http://en.wikipedia.org/wiki/Alc%C3%A1ntara_Bridge]]
	Arches appeared as early as the 2nd millennium BC in [http://en.wikipedia.org/wiki/Architecture_of_Mesopotamia '''Mesopotamia'''] but it was the [http://en.wikipedia.org/wiki/Ancient_Roman_architecture '''Ancient Romans'''] who were the first to apply the technique to a wide range of structures and the use of arches springing directly from the tops of columns, as with the [http://en.wikipedia.org/wiki/Triumphal_Arch '''Triumphal Arch'''].		Arches appeared as early as the 2nd millennium BC in [http://en.wikipedia.org/wiki/Architecture_of_Mesopotamia '''Mesopotamia'''] but it was the [http://en.wikipedia.org/wiki/Ancient_Roman_architecture '''Ancient Romans'''] who were the first to apply the technique to a wide range of structures and the use of arches springing directly from the tops of columns, as with the [http://en.wikipedia.org/wiki/Triumphal_Arch '''Triumphal Arch'''].

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	[[File:GreatMosqueKairouan.jpg\|250px\|right\|Horseshoe Arches in the Great Mosque of Kairouan, Tunisia\|link=~~https~~://en.wikipedia.org/wiki/Great_Mosque_of_Kairouan]]		[[File:GreatMosqueKairouan.jpg\|250px\|right\|Horseshoe Arches in the Great Mosque of Kairouan, Tunisia\|link=http://en.wikipedia.org/wiki/Great_Mosque_of_Kairouan]]
	=====Horseshoe Arch=====		=====Horseshoe Arch=====
	At its simplest, a horseshoe arch is a semicircular ''(or Roman)'' arch which continues downwards to occupy more than a semicircle - ie the arch extends beyond the horizontal diameter of the semi-circle to complete an arch of perhaps three-quarters of a circle.		At its simplest, a horseshoe arch is a semicircular ''(or Roman)'' arch which continues downwards to occupy more than a semicircle - ie the arch extends beyond the horizontal diameter of the semi-circle to complete an arch of perhaps three-quarters of a circle.
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	[[File:GothicBridgeTruyereRiver.JPG\|250px\|right\|Gothic Bridge across the Truyere River, Southern France\|link=~~https~~://fr.wikipedia.org/wiki/Entraygues-sur-Truy%C3%A8re]]		[[File:GothicBridgeTruyereRiver.JPG\|250px\|right\|Gothic Bridge across the Truyere River, Southern France\|link=http://fr.wikipedia.org/wiki/Entraygues-sur-Truy%C3%A8re]]
	=====Gothic Arch=====		=====Gothic Arch=====
	During the 12th century Romanesque developed into the Gothic style, which is characterised by a pointed arches or [http://en.wikipedia.org/wiki/Ogive '''ogive'''].		During the 12th century Romanesque developed into the Gothic style, which is characterised by a pointed arches or [http://en.wikipedia.org/wiki/Ogive '''ogive'''].
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	[[File:HedinghamCastle.jpg\|250px\|right\|Tudor arches at Hedingham Castle, Essex, UK\|link=~~https~~://en.wikipedia.org/wiki/Hedingham_Castle]]		[[File:HedinghamCastle.jpg\|250px\|right\|Tudor arches at Hedingham Castle, Essex, UK\|link=http://en.wikipedia.org/wiki/Hedingham_Castle]]
	=====Tudor Arch=====		=====Tudor Arch=====
	Also known as a [http://en.wikipedia.org/wiki/Four-centred_arch '''four-centred arch'''], Tudor arches are a wider and flatter development of the Gothic arch. They are often seen above doorways and windows. Buildings with such large windows, divided up with tall slim [http://en.wikipedia.org/wiki/Mullions '''mullions'''] and filled with decorative stone [http://en.wikipedia.org/wiki/Tracery '''tracery'''] and [http://en.wikipedia.org/wiki/Stained_glass '''stained glass'''], were a feature of the [http://en.wikipedia.org/wiki/Perpendicular_architecture#Perpendicular_Gothic '''Perpendicular'''] style of architecture		Also known as a [http://en.wikipedia.org/wiki/Four-centred_arch '''four-centred arch'''], Tudor arches are a wider and flatter development of the Gothic arch. They are often seen above doorways and windows. Buildings with such large windows, divided up with tall slim [http://en.wikipedia.org/wiki/Mullions '''mullions'''] and filled with decorative stone [http://en.wikipedia.org/wiki/Tracery '''tracery'''] and [http://en.wikipedia.org/wiki/Stained_glass '''stained glass'''], were a feature of the [http://en.wikipedia.org/wiki/Perpendicular_architecture#Perpendicular_Gothic '''Perpendicular'''] style of architecture
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	=====Elliptical Arch=====		=====Elliptical Arch=====
	[[File:MaidenheadRailwayBridge.jpg\|250px\|right\|Elliptical Arches under the Maidenhead Railway Bridge, Berkshire/Buckinghamshire, UK\|link=~~https~~://en.wikipedia.org/wiki/Maidenhead_Railway_Bridge]]		[[File:MaidenheadRailwayBridge.jpg\|250px\|right\|Elliptical Arches under the Maidenhead Railway Bridge, Berkshire/Buckinghamshire, UK\|link=http://en.wikipedia.org/wiki/Maidenhead_Railway_Bridge]]
	The development and expansion of canals and railways during the 18th and 19th centuries greatly increased the need for bridges, often brick built, to cross rivers, valleys and roads.		The development and expansion of canals and railways during the 18th and 19th centuries greatly increased the need for bridges, often brick built, to cross rivers, valleys and roads.

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	[[File:TyneBridge.jpg\|250px\|right\|Tyne Bridge\|link=~~https~~://en.wikipedia.org/wiki/Tyne_Bridge]]		[[File:TyneBridge.jpg\|250px\|right\|Tyne Bridge\|link=http://en.wikipedia.org/wiki/Tyne_Bridge]]
	The need for railway lines to avoid sharp bends, led to the development of the [http://en.wikipedia.org/wiki/Skew_arch '''Skew Arch'''] which enabled roads to be crossed at an angle.		The need for railway lines to avoid sharp bends, led to the development of the [http://en.wikipedia.org/wiki/Skew_arch '''Skew Arch'''] which enabled roads to be crossed at an angle.

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	[[File:HulmeParabolicArchBridge.jpg\|250px\|right\|Hulme Arch Bridge\|link=~~https~~://en.wikipedia.org/wiki/Hulme_Arch_Bridge]]		[[File:HulmeParabolicArchBridge.jpg\|250px\|right\|Hulme Arch Bridge\|link=http://en.wikipedia.org/wiki/Hulme_Arch_Bridge]]
	=====Parabolic Arch=====		=====Parabolic Arch=====
	The development of [http://en.wikipedia.org/wiki/Arch#Fixed_arch_vs_hinged_arch '''Two-Hinged'''] and [http://en.wikipedia.org/wiki/Arch#Fixed_arch_vs_hinged_arch '''Three-Hinged'''] arches reduce stress caused by thermal change which simplifies further the design of foundations.		The development of [http://en.wikipedia.org/wiki/Arch#Fixed_arch_vs_hinged_arch '''Two-Hinged'''] and [http://en.wikipedia.org/wiki/Arch#Fixed_arch_vs_hinged_arch '''Three-Hinged'''] arches reduce stress caused by thermal change which simplifies further the design of foundations.

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			[[File:The Iron Bridge. - geograph.org.uk - 424235.jpg\|400px\|right\|The Iron Bridge. - geograph.org.uk - 424235]]
			__TOC__


	=====Roman Arch=====		=====Roman Arch=====
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	For wider spans, a '''[[Parabola\|parabola]]''' is now chosen as the curve used to create the arch and, more recently, a '''[[Catenary Arch Model\|catenary]]''' ''(the curve naturally created by a hanging chain)''.		For wider spans, a '''[[Parabola\|parabola]]''' is now chosen as the curve used to create the arch and, more recently, a '''[[Catenary Arch Model\|catenary]]''' ''(the curve naturally created by a hanging chain)''.


			{{Bridge Models Buyers Guide}}

	[[Category:Bridges]]		[[Category:Bridges]]

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	=====Roman Arch=====		=====Roman Arch=====
	[[File:Alcantara.JPG\|~~300px~~\|right\|Roman arch at Alcantara, Spain\|link=https://en.wikipedia.org/wiki/Alc%C3%A1ntara_Bridge]]		[[File:Alcantara.JPG\|250px\|right\|Roman arch at Alcantara, Spain\|link=https://en.wikipedia.org/wiki/Alc%C3%A1ntara_Bridge]]
	Arches appeared as early as the 2nd millennium BC in [http://en.wikipedia.org/wiki/Architecture_of_Mesopotamia '''Mesopotamia'''] but it was the [http://en.wikipedia.org/wiki/Ancient_Roman_architecture '''Ancient Romans'''] who were the first to apply the technique to a wide range of structures and the use of arches springing directly from the tops of columns, as with the [http://en.wikipedia.org/wiki/Triumphal_Arch '''Triumphal Arch'''].		Arches appeared as early as the 2nd millennium BC in [http://en.wikipedia.org/wiki/Architecture_of_Mesopotamia '''Mesopotamia'''] but it was the [http://en.wikipedia.org/wiki/Ancient_Roman_architecture '''Ancient Romans'''] who were the first to apply the technique to a wide range of structures and the use of arches springing directly from the tops of columns, as with the [http://en.wikipedia.org/wiki/Triumphal_Arch '''Triumphal Arch'''].

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			[[File:GreatMosqueKairouan.jpg\|250px\|right\|Horseshoe Arches in the Great Mosque of Kairouan, Tunisia\|link=https://en.wikipedia.org/wiki/Great_Mosque_of_Kairouan]]
	=====Horseshoe Arch=====		=====Horseshoe Arch=====
	~~[[File:GreatMosqueKairouan.jpg\|300px\|right\|Horseshoe Arches in the Great Mosque of Kairouan, Tunisia\|link=https://en.wikipedia.org/wiki/Great_Mosque_of_Kairouan]]~~
	At its simplest, a horseshoe arch is a semicircular ''(or Roman)'' arch which continues downwards to occupy more than a semicircle - ie the arch extends beyond the horizontal diameter of the semi-circle to complete an arch of perhaps three-quarters of a circle.		At its simplest, a horseshoe arch is a semicircular ''(or Roman)'' arch which continues downwards to occupy more than a semicircle - ie the arch extends beyond the horizontal diameter of the semi-circle to complete an arch of perhaps three-quarters of a circle.

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			[[File:GothicBridgeTruyereRiver.JPG\|250px\|right\|Gothic Bridge across the Truyere River, Southern France\|link=https://fr.wikipedia.org/wiki/Entraygues-sur-Truy%C3%A8re]]
	=====Gothic Arch=====		=====Gothic Arch=====
	~~[[File:GothicBridgeTruyereRiver.JPG\|300px\|right\|Gothic Bridge across the Truyere River, Southern France\|link=https://fr.wikipedia.org/wiki/Entraygues-sur-Truy%C3%A8re]]~~
	During the 12th century Romanesque developed into the Gothic style, which is characterised by a pointed arches or [http://en.wikipedia.org/wiki/Ogive '''ogive'''].		During the 12th century Romanesque developed into the Gothic style, which is characterised by a pointed arches or [http://en.wikipedia.org/wiki/Ogive '''ogive'''].

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			[[File:HedinghamCastle.jpg\|250px\|right\|Tudor arches at Hedingham Castle, Essex, UK\|link=https://en.wikipedia.org/wiki/Hedingham_Castle]]
	=====Tudor Arch=====		=====Tudor Arch=====
	~~[[File:HedinghamCastle.jpg\|300px\|right\|Tudor arches at Hedingham Castle, Essex, UK\|link=https://en.wikipedia.org/wiki/Hedingham_Castle]]~~
	Also known as a [http://en.wikipedia.org/wiki/Four-centred_arch '''four-centred arch'''], Tudor arches are a wider and flatter development of the Gothic arch. They are often seen above doorways and windows. Buildings with such large windows, divided up with tall slim [http://en.wikipedia.org/wiki/Mullions '''mullions'''] and filled with decorative stone [http://en.wikipedia.org/wiki/Tracery '''tracery'''] and [http://en.wikipedia.org/wiki/Stained_glass '''stained glass'''], were a feature of the [http://en.wikipedia.org/wiki/Perpendicular_architecture#Perpendicular_Gothic '''Perpendicular'''] style of architecture		Also known as a [http://en.wikipedia.org/wiki/Four-centred_arch '''four-centred arch'''], Tudor arches are a wider and flatter development of the Gothic arch. They are often seen above doorways and windows. Buildings with such large windows, divided up with tall slim [http://en.wikipedia.org/wiki/Mullions '''mullions'''] and filled with decorative stone [http://en.wikipedia.org/wiki/Tracery '''tracery'''] and [http://en.wikipedia.org/wiki/Stained_glass '''stained glass'''], were a feature of the [http://en.wikipedia.org/wiki/Perpendicular_architecture#Perpendicular_Gothic '''Perpendicular'''] style of architecture

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	=====Elliptical Arch=====		=====Elliptical Arch=====
	[[File:MaidenheadRailwayBridge.jpg\|~~300px~~\|right\|Elliptical Arches under the Maidenhead Railway Bridge, Berkshire/Buckinghamshire, UK\|link=https://en.wikipedia.org/wiki/Maidenhead_Railway_Bridge]]		[[File:MaidenheadRailwayBridge.jpg\|250px\|right\|Elliptical Arches under the Maidenhead Railway Bridge, Berkshire/Buckinghamshire, UK\|link=https://en.wikipedia.org/wiki/Maidenhead_Railway_Bridge]]
	The development and expansion of canals and railways during the 18th and 19th centuries greatly increased the need for bridges, often brick built, to cross rivers, valleys and roads.		The development and expansion of canals and railways during the 18th and 19th centuries greatly increased the need for bridges, often brick built, to cross rivers, valleys and roads.


	Although used previously, segmented arches, sometimes elliptical and often in brick, provided a means of creating bridges that were wide in relation to their height, an important feature for Victorian engineers who needed keep gradients to a minimum for their railways, but this at the cost of increased side thrust at the abutments. Greater use of [http://en.wikipedia.org/wiki/Concrete '''concrete'''], [http://en.wikipedia.org/wiki/Cast_iron '''cast'''] and [http://en.wikipedia.org/wiki/Wrought_iron '''wrought iron'''] allowed the development of the [http://en.wikipedia.org/wiki/Through_arch_bridge '''Through Arch'''] to solve this problem.		Although used previously, segmented arches, sometimes elliptical and often in brick, provided a means of creating bridges that were wide in relation to their height, an important feature for Victorian engineers who needed keep gradients to a minimum for their railways, but this at the cost of increased side thrust at the abutments.


			Greater use of [http://en.wikipedia.org/wiki/Concrete '''concrete'''], [http://en.wikipedia.org/wiki/Cast_iron '''cast'''] and [http://en.wikipedia.org/wiki/Wrought_iron '''wrought iron'''] allowed the development of the [http://en.wikipedia.org/wiki/Through_arch_bridge '''Through Arch'''] to solve this problem.


			[[File:TyneBridge.jpg\|250px\|right\|Tyne Bridge\|link=https://en.wikipedia.org/wiki/Tyne_Bridge]]
	The need for railway lines to avoid sharp bends, led to the development of the [http://en.wikipedia.org/wiki/Skew_arch '''Skew Arch'''] which enabled roads to be crossed at an angle.		The need for railway lines to avoid sharp bends, led to the development of the [http://en.wikipedia.org/wiki/Skew_arch '''Skew Arch'''] which enabled roads to be crossed at an angle.


	=====~~Parabolic~~ Arch=====		=====Through Arch=====
	~~[[File:TyneBridge.jpg\|300px\|right\|Tyne Bridge\|link=https://en.wikipedia.org/wiki/Tyne_Bridge]]~~		Modern arches of [http://en.wikipedia.org/wiki/Steel '''steel'''], [http://en.wikipedia.org/wiki/Reinforced_concrete '''reinforced'''] and [http://en.wikipedia.org/wiki/Pre-stressed_concrete '''pre-stressed concrete'''], or laminated wood are highly rigid and lightweight, so that the horizontal thrust against the supports is small; this thrust can be further reduced by stretching a '''[[Tie\|tie]]''' between the ends of the arch and often in the form of a deck - creating a '''Through Arch'''.
	Modern arches of [http://en.wikipedia.org/wiki/Steel '''steel'''], [http://en.wikipedia.org/wiki/Reinforced_concrete '''reinforced'''] and [http://en.wikipedia.org/wiki/Pre-stressed_concrete '''pre-stressed concrete'''], or laminated wood are highly rigid and lightweight, so that the horizontal thrust against the supports is small; this thrust can be further reduced by stretching a '''[[Tie\|tie]]''' between the ends of the arch and often in the form of a deck - creating a Through Arch.


			[[File:HulmeParabolicArchBridge.jpg\|250px\|right\|Hulme Arch Bridge\|link=https://en.wikipedia.org/wiki/Hulme_Arch_Bridge]]
			=====Parabolic Arch=====
	The development of [http://en.wikipedia.org/wiki/Arch#Fixed_arch_vs_hinged_arch '''Two-Hinged'''] and [http://en.wikipedia.org/wiki/Arch#Fixed_arch_vs_hinged_arch '''Three-Hinged'''] arches reduce stress caused by thermal change which simplifies further the design of foundations.		The development of [http://en.wikipedia.org/wiki/Arch#Fixed_arch_vs_hinged_arch '''Two-Hinged'''] and [http://en.wikipedia.org/wiki/Arch#Fixed_arch_vs_hinged_arch '''Three-Hinged'''] arches reduce stress caused by thermal change which simplifies further the design of foundations.

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← Older revision		Revision as of 10:23, 10 January 2016
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	=====Parabolic Arch=====		=====Parabolic Arch=====
	[[File:TyneBridge.jpg\|300px\|right]]		[[File:TyneBridge.jpg\|300px\|right\|Tyne Bridge\|link=https://en.wikipedia.org/wiki/Tyne_Bridge]]
	Modern arches of [http://en.wikipedia.org/wiki/Steel '''steel'''], [http://en.wikipedia.org/wiki/Reinforced_concrete '''reinforced'''] and [http://en.wikipedia.org/wiki/Pre-stressed_concrete '''pre-stressed concrete'''], or laminated wood are highly rigid and lightweight, so that the horizontal thrust against the supports is small; this thrust can be further reduced by stretching a '''[[Tie\|tie]]''' between the ends of the arch and often in the form of a deck - creating a Through Arch.		Modern arches of [http://en.wikipedia.org/wiki/Steel '''steel'''], [http://en.wikipedia.org/wiki/Reinforced_concrete '''reinforced'''] and [http://en.wikipedia.org/wiki/Pre-stressed_concrete '''pre-stressed concrete'''], or laminated wood are highly rigid and lightweight, so that the horizontal thrust against the supports is small; this thrust can be further reduced by stretching a '''[[Tie\|tie]]''' between the ends of the arch and often in the form of a deck - creating a Through Arch.

DT Online: Added link

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← Older revision		Revision as of 20:55, 23 December 2015
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	=====Parabolic Arch=====		=====Parabolic Arch=====
	[[File:TyneBridge.jpg\|300px\|right]]		[[File:TyneBridge.jpg\|300px\|right]]
	Modern arches of [http://en.wikipedia.org/wiki/Steel '''steel'''], [http://en.wikipedia.org/wiki/Reinforced_concrete '''reinforced'''] and [http://en.wikipedia.org/wiki/Pre-stressed_concrete '''pre-stressed concrete'''], or laminated wood are highly rigid and lightweight, so that the horizontal thrust against the supports is small; this thrust can be further reduced by stretching a tie between the ends of the arch and often in the form of a deck - creating a Through Arch.		Modern arches of [http://en.wikipedia.org/wiki/Steel '''steel'''], [http://en.wikipedia.org/wiki/Reinforced_concrete '''reinforced'''] and [http://en.wikipedia.org/wiki/Pre-stressed_concrete '''pre-stressed concrete'''], or laminated wood are highly rigid and lightweight, so that the horizontal thrust against the supports is small; this thrust can be further reduced by stretching a '''[[Tie\|tie]]''' between the ends of the arch and often in the form of a deck - creating a Through Arch.

DT Online: Corrected Link

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← Older revision		Revision as of 19:04, 23 December 2015
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	For wider spans, a '''[[Parabola\|parabola]]''' is now chosen as the curve used to create the arch and, more recently, a '''[[Catenary Arch\|catenary]]''' ''(the curve naturally created by a hanging chain)''.		For wider spans, a '''[[Parabola\|parabola]]''' is now chosen as the curve used to create the arch and, more recently, a '''[[Catenary Arch Model\|catenary]]''' ''(the curve naturally created by a hanging chain)''.

	[[Category:Bridges]]		[[Category:Bridges]]

DT Online: Created article

2015-12-19T11:55:36Z

Created article

New page

=====Roman Arch=====
[[File:Alcantara.JPG|300px|right|Roman arch at Alcantara, Spain|link=https://en.wikipedia.org/wiki/Alc%C3%A1ntara_Bridge]]
Arches appeared as early as the 2nd millennium BC in [http://en.wikipedia.org/wiki/Architecture_of_Mesopotamia '''Mesopotamia'''] but it was the [http://en.wikipedia.org/wiki/Ancient_Roman_architecture '''Ancient Romans'''] who were the first to apply the technique to a wide range of structures and the use of arches springing directly from the tops of columns, as with the [http://en.wikipedia.org/wiki/Triumphal_Arch '''Triumphal Arch'''].

This was very widely adopted in medieval Western, [http://en.wikipedia.org/wiki/Byzantine_architecture '''Byzantine'''] and [http://en.wikipedia.org/wiki/Islamic_architecture '''Islamic'''] architecture. In Medieval Europe it became known as [http://en.wikipedia.org/wiki/Romanesque_architecture '''Romanesque'''] architecture and is characterised by semi-circular arches. In England this style became traditionally referred to as [http://en.wikipedia.org/wiki/Norman_architecture '''Norman'''] architecture.

=====Horseshoe Arch=====
[[File:GreatMosqueKairouan.jpg|300px|right|Horseshoe Arches in the Great Mosque of Kairouan, Tunisia|link=https://en.wikipedia.org/wiki/Great_Mosque_of_Kairouan]]
At its simplest, a horseshoe arch is a semicircular ''(or Roman)'' arch which continues downwards to occupy more than a semicircle - ie the arch extends beyond the horizontal diameter of the semi-circle to complete an arch of perhaps three-quarters of a circle.

The design was known in Roman times but it is the emblematic arch of Islamic architecture which recognised that the increased height would allow more light to enter interior spaces, light being important to Muslim culture.

The line of voussoirs curves inwards towards the bottom which creates more support for the [http://en.wikipedia.org/wiki/Springer_%28architecture%29 '''springer'''] and perhaps results in the lower sides of adjacent arches sharing some of the load by pressing against each other. Certainly, horseshoe arches were able to be supported by pillars of reduced size thus creating a greater feeling of space.

=====Gothic Arch=====
[[File:GothicBridgeTruyereRiver.JPG|300px|right|Gothic Bridge across the Truyere River, Southern France|link=https://fr.wikipedia.org/wiki/Entraygues-sur-Truy%C3%A8re]]
During the 12th century Romanesque developed into the Gothic style, which is characterised by a pointed arches or [http://en.wikipedia.org/wiki/Ogive '''ogive'''].

The advantage to using a pointed arch, rather than a circular arch, is that the arch action in a pointed arch produces less thrust at the base. This innovation allowed for taller and more closely spaced openings, typical of Gothic architecture.

Tall and narrow pointed arches are known as [http://en.wikipedia.org/wiki/Lancet_window '''Lancet Arches'''] and were often grouped in clusters of three or five. The name 'lancet' derives from its resemblance to a lance.

=====Tudor Arch=====
[[File:HedinghamCastle.jpg|300px|right|Tudor arches at Hedingham Castle, Essex, UK|link=https://en.wikipedia.org/wiki/Hedingham_Castle]]
Also known as a [http://en.wikipedia.org/wiki/Four-centred_arch '''four-centred arch'''], Tudor arches are a wider and flatter development of the Gothic arch. They are often seen above doorways and windows. Buildings with such large windows, divided up with tall slim [http://en.wikipedia.org/wiki/Mullions '''mullions'''] and filled with decorative stone [http://en.wikipedia.org/wiki/Tracery '''tracery'''] and [http://en.wikipedia.org/wiki/Stained_glass '''stained glass'''], were a feature of the [http://en.wikipedia.org/wiki/Perpendicular_architecture#Perpendicular_Gothic '''Perpendicular'''] style of architecture

There are few bridges which employ the Tudor arch but a Tudor style bridge replaced the orginal gatehouse/drawbridge at Hedingham Castle and is characteristic of most of the bridges on Brunel's railway line between Bristol and Bath - perhaps to reflect the Tudor architecture of Bristol.

=====Elliptical Arch=====
[[File:MaidenheadRailwayBridge.jpg|300px|right|Elliptical Arches under the Maidenhead Railway Bridge, Berkshire/Buckinghamshire, UK|link=https://en.wikipedia.org/wiki/Maidenhead_Railway_Bridge]]
The development and expansion of canals and railways during the 18th and 19th centuries greatly increased the need for bridges, often brick built, to cross rivers, valleys and roads.

Although used previously, segmented arches, sometimes elliptical and often in brick, provided a means of creating bridges that were wide in relation to their height, an important feature for Victorian engineers who needed keep gradients to a minimum for their railways, but this at the cost of increased side thrust at the abutments. Greater use of [http://en.wikipedia.org/wiki/Concrete '''concrete'''], [http://en.wikipedia.org/wiki/Cast_iron '''cast'''] and [http://en.wikipedia.org/wiki/Wrought_iron '''wrought iron'''] allowed the development of the [http://en.wikipedia.org/wiki/Through_arch_bridge '''Through Arch'''] to solve this problem.

The need for railway lines to avoid sharp bends, led to the development of the [http://en.wikipedia.org/wiki/Skew_arch '''Skew Arch'''] which enabled roads to be crossed at an angle.

=====Parabolic Arch=====
[[File:TyneBridge.jpg|300px|right]]
Modern arches of [http://en.wikipedia.org/wiki/Steel '''steel'''], [http://en.wikipedia.org/wiki/Reinforced_concrete '''reinforced'''] and [http://en.wikipedia.org/wiki/Pre-stressed_concrete '''pre-stressed concrete'''], or laminated wood are highly rigid and lightweight, so that the horizontal thrust against the supports is small; this thrust can be further reduced by stretching a tie between the ends of the arch and often in the form of a deck - creating a Through Arch.

The development of [http://en.wikipedia.org/wiki/Arch#Fixed_arch_vs_hinged_arch '''Two-Hinged'''] and [http://en.wikipedia.org/wiki/Arch#Fixed_arch_vs_hinged_arch '''Three-Hinged'''] arches reduce stress caused by thermal change which simplifies further the design of foundations.

For wider spans, a '''[[Parabola|parabola]]''' is now chosen as the curve used to create the arch and, more recently, a '''[[Catenary Arch|catenary]]''' ''(the curve naturally created by a hanging chain)''.

[[Category:Bridges]]