Mabey Logistic Support Bridge
Encyclopedia
The Mabey Logistic Support Bridge (in the United States, the Mabey-Johnson Bridge) is a portable pre-fabricated
truss
bridge
, designed for use by military engineering units to upgrade routes for heavier traffic, replace civilian bridges damaged by enemy action or floods etc, replace assault
and general support bridges and to provide a long span floating bridge capability. The bridge is a variant of the Mabey Compact 200 bridge, with alterations made to suit the military user as well as a ramp system that will provides ground clearance to civilian and military vehicles.
The Mabey Logistic Support Bridge originated from the Bailey bridge
concept. Compared with World War II
material in use throughout the world, LSB is manufactured with chosen modern steel grades, with a strong steel deck system. With strong deep transoms, there are only two per bay instead of the four previously needed on Bailey.
Beyond the need for the re-opening of communications, Logistic Support Bridge-based equipment (Compact 200) can be used as a rescue bridge for relief in natural disaster situations or as a civilian bridge for semi-permanent bridging to open up communications in some of the most remote regions of the world.
, Gloucestershire (Mabey Group has another factory in Chepstow
which manufactures bridge girders). The name LSB was given by the British Army
(Royal Engineers
) to supply bridging to satisfy their specific requirements for a logistic or line of communication bridging. The LSB went into service with the British Army on 21 December 2001. The system is proved and approved by a number of NATO forces.
Armies from a number of countries around the world own equipment or have trained and deployed on the system, notably during the crisis in the Balkans
. These Armies include Argentina
, Austria
, Belgium
, Brazil
, Bulgaria
, Cambodia
, Canada
, Chile
, Denmark
, Ecuador
, Finland
, France
, Germany
, Greece
, Hungary
, Ireland
, Italy
, Malaysia, Nepal
, Netherlands
, Romania
, Sri Lanka
, Slovakia
, Slovenia
, Spain
, Sweden
, Switzerland
, Tanzania
, Turkey
, Venezuela
, United Kingdom
, United States
.
The bridge has been built in many locations across Iraq and Afghanistan by the U.S. Naval Mobile Construction Battalion
s (Seabees) and the U.S. Army Corps of Engineers.
After pushing the bridge over the gap, the launching nose is dismantled and the bridge is jacked down onto its bearings. The launching nose is largely constructed from standard bridge components.
If the bridge is relatively short in terms of the number of spans, it may be possible to launch the complete bridge from one bank. On a long span bridge, launching intermediate spans and floating them into position on intermediate piers is more practical.
Prefabrication
Prefabrication is the practice of assembling components of a structure in a factory or other manufacturing site, and transporting complete assemblies or sub-assemblies to the construction site where the structure is to be located...
truss
Truss
In architecture and structural engineering, a truss is a structure comprising one or more triangular units constructed with straight members whose ends are connected at joints referred to as nodes. External forces and reactions to those forces are considered to act only at the nodes and result in...
bridge
Bridge
A bridge is a structure built to span physical obstacles such as a body of water, valley, or road, for the purpose of providing passage over the obstacle...
, designed for use by military engineering units to upgrade routes for heavier traffic, replace civilian bridges damaged by enemy action or floods etc, replace assault
Armoured vehicle-launched bridge
An armoured vehicle-launched bridge is a combat support vehicle, sometimes regarded as a subtype of combat engineering vehicle, designed to assist militaries in rapidly deploying tanks and other armoured fighting vehicles across rivers. The AVLB is usually a tracked vehicle converted from a tank...
and general support bridges and to provide a long span floating bridge capability. The bridge is a variant of the Mabey Compact 200 bridge, with alterations made to suit the military user as well as a ramp system that will provides ground clearance to civilian and military vehicles.
Description
The Logistic Support Bridge is a non-assault bridge for the movement of supplies and the re-opening of communications. It is a low-cost system that can be used widely throughout the support area, as well as for a range of defined applications. All types of vehicles including civilian vehicles with low ground clearances are accommodated.The Mabey Logistic Support Bridge originated from the Bailey bridge
Bailey bridge
The Bailey bridge is a type of portable, pre-fabricated, truss bridge. It was developed by the British during World War II for military use and saw extensive use by both British and the American military engineering units....
concept. Compared with World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
material in use throughout the world, LSB is manufactured with chosen modern steel grades, with a strong steel deck system. With strong deep transoms, there are only two per bay instead of the four previously needed on Bailey.
Beyond the need for the re-opening of communications, Logistic Support Bridge-based equipment (Compact 200) can be used as a rescue bridge for relief in natural disaster situations or as a civilian bridge for semi-permanent bridging to open up communications in some of the most remote regions of the world.
Users
The bridge is manufactured by Mabey & Johnson at their factory in LydneyLydney
Lydney is a small town and civil parish in the English county of Gloucestershire. It is located on the west bank of the River Severn, close to the Forest of Dean. The town lies on the A48 road, next to the Lydney Park gardens with its Roman temple in honour of Nodens.-Transport:The Severn Railway...
, Gloucestershire (Mabey Group has another factory in Chepstow
Chepstow
Chepstow is a town in Monmouthshire, Wales, adjoining the border with Gloucestershire, England. It is located on the River Wye, close to its confluence with the River Severn, and close to the western end of the Severn Bridge on the M48 motorway...
which manufactures bridge girders). The name LSB was given by the British Army
British Army
The British Army is the land warfare branch of Her Majesty's Armed Forces in the United Kingdom. It came into being with the unification of the Kingdom of England and Scotland into the Kingdom of Great Britain in 1707. The new British Army incorporated Regiments that had already existed in England...
(Royal Engineers
Royal Engineers
The Corps of Royal Engineers, usually just called the Royal Engineers , and commonly known as the Sappers, is one of the corps of the British Army....
) to supply bridging to satisfy their specific requirements for a logistic or line of communication bridging. The LSB went into service with the British Army on 21 December 2001. The system is proved and approved by a number of NATO forces.
Armies from a number of countries around the world own equipment or have trained and deployed on the system, notably during the crisis in the Balkans
Balkans
The Balkans is a geopolitical and cultural region of southeastern Europe...
. These Armies include Argentina
Argentina
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...
, Austria
Austria
Austria , officially the Republic of Austria , is a landlocked country of roughly 8.4 million people in Central Europe. It is bordered by the Czech Republic and Germany to the north, Slovakia and Hungary to the east, Slovenia and Italy to the south, and Switzerland and Liechtenstein to the...
, Belgium
Belgium
Belgium , officially the Kingdom of Belgium, is a federal state in Western Europe. It is a founding member of the European Union and hosts the EU's headquarters, and those of several other major international organisations such as NATO.Belgium is also a member of, or affiliated to, many...
, Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
, Bulgaria
Bulgaria
Bulgaria , officially the Republic of Bulgaria , is a parliamentary democracy within a unitary constitutional republic in Southeast Europe. The country borders Romania to the north, Serbia and Macedonia to the west, Greece and Turkey to the south, as well as the Black Sea to the east...
, Cambodia
Cambodia
Cambodia , officially known as the Kingdom of Cambodia, is a country located in the southern portion of the Indochina Peninsula in Southeast Asia...
, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
, Chile
Chile
Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...
, Denmark
Denmark
Denmark is a Scandinavian country in Northern Europe. The countries of Denmark and Greenland, as well as the Faroe Islands, constitute the Kingdom of Denmark . It is the southernmost of the Nordic countries, southwest of Sweden and south of Norway, and bordered to the south by Germany. Denmark...
, Ecuador
Ecuador
Ecuador , officially the Republic of Ecuador is a representative democratic republic in South America, bordered by Colombia on the north, Peru on the east and south, and by the Pacific Ocean to the west. It is one of only two countries in South America, along with Chile, that do not have a border...
, Finland
Finland
Finland , officially the Republic of Finland, is a Nordic country situated in the Fennoscandian region of Northern Europe. It is bordered by Sweden in the west, Norway in the north and Russia in the east, while Estonia lies to its south across the Gulf of Finland.Around 5.4 million people reside...
, France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
, Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
, Greece
Greece
Greece , officially the Hellenic Republic , and historically Hellas or the Republic of Greece in English, is a country in southeastern Europe....
, Hungary
Hungary
Hungary , officially the Republic of Hungary , is a landlocked country in Central Europe. It is situated in the Carpathian Basin and is bordered by Slovakia to the north, Ukraine and Romania to the east, Serbia and Croatia to the south, Slovenia to the southwest and Austria to the west. The...
, Ireland
Ireland
Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...
, Italy
Italy
Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...
, Malaysia, Nepal
Nepal
Nepal , officially the Federal Democratic Republic of Nepal, is a landlocked sovereign state located in South Asia. It is located in the Himalayas and bordered to the north by the People's Republic of China, and to the south, east, and west by the Republic of India...
, Netherlands
Netherlands
The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...
, Romania
Romania
Romania is a country located at the crossroads of Central and Southeastern Europe, on the Lower Danube, within and outside the Carpathian arch, bordering on the Black Sea...
, Sri Lanka
Sri Lanka
Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka is a country off the southern coast of the Indian subcontinent. Known until 1972 as Ceylon , Sri Lanka is an island surrounded by the Indian Ocean, the Gulf of Mannar and the Palk Strait, and lies in the vicinity of India and the...
, Slovakia
Slovakia
The Slovak Republic is a landlocked state in Central Europe. It has a population of over five million and an area of about . Slovakia is bordered by the Czech Republic and Austria to the west, Poland to the north, Ukraine to the east and Hungary to the south...
, Slovenia
Slovenia
Slovenia , officially the Republic of Slovenia , is a country in Central and Southeastern Europe touching the Alps and bordering the Mediterranean. Slovenia borders Italy to the west, Croatia to the south and east, Hungary to the northeast, and Austria to the north, and also has a small portion of...
, Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...
, Sweden
Sweden
Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
, Switzerland
Switzerland
Switzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition....
, Tanzania
Tanzania
The United Republic of Tanzania is a country in East Africa bordered by Kenya and Uganda to the north, Rwanda, Burundi, and the Democratic Republic of the Congo to the west, and Zambia, Malawi, and Mozambique to the south. The country's eastern borders lie on the Indian Ocean.Tanzania is a state...
, Turkey
Turkey
Turkey , known officially as the Republic of Turkey , is a Eurasian country located in Western Asia and in East Thrace in Southeastern Europe...
, Venezuela
Venezuela
Venezuela , officially called the Bolivarian Republic of Venezuela , is a tropical country on the northern coast of South America. It borders Colombia to the west, Guyana to the east, and Brazil to the south...
, United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
, United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
.
The bridge has been built in many locations across Iraq and Afghanistan by the U.S. Naval Mobile Construction Battalion
Naval Mobile Construction Battalion
There are 9 active-duty Naval Mobile Construction Battalions — known as C.B.'s — in the United States Navy, split between the east and west coasts...
s (Seabees) and the U.S. Army Corps of Engineers.
Features
- The bridge takes military load class 80 Tracked, 110 Wheeled
- The bridge can span up to 61m
- LSB has a lane width of 4.2m
- Multi-span equipment enables the bridge to be built to any length on fixed or floating supports
- Built on a greenfield site using grillages, ground beams and ramps
- The bridge is normally built using a atc244 22 tonTonThe ton is a unit of measure. It has a long history and has acquired a number of meanings and uses over the years. It is used principally as a unit of weight, and as a unit of volume. It can also be used as a measure of energy, for truck classification, or as a colloquial term.It is derived from...
capacity craneCrane (machine)A crane is a type of machine, generally equipped with a hoist, wire ropes or chains, and sheaves, that can be used both to lift and lower materials and to move them horizontally. It uses one or more simple machines to create mechanical advantage and thus move loads beyond the normal capability of...
or a hydraulic excavatorExcavatorExcavators are heavy construction equipment consisting of a boom, stick, bucket and cab on a rotating platform . The house sits atop an undercarriage with tracks or wheels. A cable-operated excavator uses winches and steel ropes to accomplish the movements. They are a natural progression from the...
using a bucket with a lifting eye.
System description
The LSB combines standard off the shelf equipment with a range of purpose designed special equipment to meet the expectations of modern military loads and traffic expectations.- Panels —These are the main structural components of the bridge trusses. They are welded items comprising top and bottom chords interconnected by vertical and diagonal bracing. At the end of each panel, chords terminate in male lugs or eyes and at the other end in female lugs or eyes. This allows panels to be pinned together to form the bridge span. There are two different panels; a Super Panel and a High Shear Super Panel. The High Shear Super Panel is used at each end of the bridge span depending upon the loading criteria.
- Chord reinforcement —These are constructed in the same way as the chords of the bridge panels and are bolted to the panels to increase the bending capacity of the bridge. For the LSB a heavy chord reinforcement is used.
- Transoms —These are fabricated from universal beams and form the cross girders of the bridge, spanning between the panels and carrying the bridge deck. The transom is designed for the appropriate loading criteria and for LSB is designed to accommodate MLC80T/110W.
- Decks —Unlike wooden Bailey decks, the steel LSB decks are 1.05m x 3.05m and are manufactured using robotic welding technology. The decks are manufactured to have a long fatigue life and with durbar/checkered plate finish. The decks withstand both wheeled and tracked vehicles.
- Bracing —A variety of bracing members are used to connect panels to form the bridge trusses and to brace adjacent transoms to the bridge.
- Grillages and Ground Beams —On greenfield sites and when being used as an over bridge, ground beams are available that form an assembly which transmits all dead and live forces from the bridge into the ground. For a 40m (MLC80T/110W) bridge the ground bearing pressure is 200 kN/m2. The grillages are located on the top of the ground beams and accommodate the bridge bearings as well as the head of the ramp transom.
- Ramps —The slope or profile of the ramps can be adjusted to allow for the passage of a range of civilian and military traffic. The length of a standard ramp at each end of the bridge is 13.5m. The ramps are bolted to the grillages and use standard deck units supported on special transoms. These transoms can be positioned at a variety of heights depending upon the set adopted with a special ramp post. The interface between the ramp and ground is a special toe ramp unit (1.5m)
Construction
The bridge can be constructed by the cantilever launch method without the need for any temporary intermediate support. This is achieved by erecting a temporary launching nose at the front of the bridge and pushing the bridge over the gap on rollers.After pushing the bridge over the gap, the launching nose is dismantled and the bridge is jacked down onto its bearings. The launching nose is largely constructed from standard bridge components.
Floating variants
There are a number of floating versions of the Mabey LSB in use across Iraq: Floating Piers which consist of steel Flexifloat pontoon units, Landing Piers consisting of 16 pontoon units, and Intermediate Piers which consist of 8 pontoons each. Hand winches are mounted on steel trays which are bolted to the pontoons. The anchors are connected to the hand winches and pontoons via steel chain and polypropylene ropes. Special span junction decks allow for the rotation of the floating spans as the spans deflect under live load.If the bridge is relatively short in terms of the number of spans, it may be possible to launch the complete bridge from one bank. On a long span bridge, launching intermediate spans and floating them into position on intermediate piers is more practical.