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Meghna Bridge
Meghna Bridge is a road bridge in Bangladesh. It was built with the assistance of Japan and officially named Japan Bangladesh Friendship Bridge 1, but it is popularly known as Meghna Bridge. According to a study conducted in 2004 by the Embassy of Japan in Bangladesh, residents living around the Meghna Bridge recognized several positive impacts after the construction of the bridge.The basic study on the present situation of the previous grant aid project for the bridges in Bangladesh ''Embassy of Japan in Bangladesh'' Location Meghna Bridge is southeast of Dhaka across the[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bangladesh
Bangladesh (}, ), officially the People's Republic of Bangladesh, is a country in South Asia. It is the eighth-most populous country in the world, with a population exceeding 165 million people in an area of . Bangladesh is among the most densely populated countries in the world, and shares land borders with India to the west, north, and east, and Myanmar to the southeast; to the south it has a coastline along the Bay of Bengal. It is narrowly separated from Bhutan and Nepal by the Siliguri Corridor; and from China by the Indian state of Sikkim in the north. Dhaka, the capital and largest city, is the nation's political, financial and cultural centre. Chittagong, the second-largest city, is the busiest port on the Bay of Bengal. The official language is Bengali, one of the easternmost branches of the Indo-European language family. Bangladesh forms the sovereign part of the historic and ethnolinguistic region of Bengal, which was divided during the Partition of India in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Expansion Joint
An expansion joint, or movement joint, is an assembly designed to hold parts together while safely absorbing temperature-induced expansion and contraction of building materials, and vibration, or to allow movement due to ground settlement or seismic activity. They are commonly found between sections of buildings, bridges, sidewalks, railway tracks, piping systems, ships, and other structures. Building faces, concrete slabs, and pipelines expand and contract due to warming and cooling from seasonal variation, or due to other heat sources. Before expansion joint gaps were built into these structures, they would crack under the stress induced. Bridge expansion joints Bridge expansion joints are designed to allow for continuous traffic between structures while accommodating movement, shrinkage, and temperature variations on reinforced and prestressed concrete, composite, and steel structures. They stop the bridge from bending out of place in extreme conditions, and also allow eno ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urbanization
Urbanization (or urbanisation) refers to the population shift from rural to urban areas, the corresponding decrease in the proportion of people living in rural areas, and the ways in which societies adapt to this change. It is predominantly the process by which towns and cities are formed and become larger as more people begin living and working in central areas. Although the two concepts are sometimes used interchangeably, urbanization should be distinguished from urban growth. Urbanization refers to the ''proportion'' of the total national population living in areas classified as urban, whereas urban growth strictly refers to the ''absolute'' number of people living in those areas. It is predicted that by 2050 about 64% of the developing world and 86% of the developed world will be urbanized. That is equivalent to approximately 3 billion urbanites by 2050, much of which will occur in Africa and Asia. Notably, the United Nations has also recently projected that nearly all gl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drainage
Drainage is the natural or artificial removal of a surface's water and sub-surface water from an area with excess of water. The internal drainage of most agricultural soils is good enough to prevent severe waterlogging (anaerobic conditions that harm root growth), but many soils need artificial drainage to improve production or to manage water supplies. History Early history The Indus Valley civilization had sewerage and drainage systems. All houses in the major cities of Harappa and Mohenjo-daro had access to water and drainage facilities. Waste water was directed to covered gravity sewers, which lined the major streets. 18th and 19th century The invention of hollow-pipe drainage is credited to Sir Hugh Dalrymple, who died in 1753. Current practices Geotextiles New storm water drainage systems incorporate geotextile filters that retain and prevent fine grains of soil from passing into and clogging the drain. Geotextiles are synthetic textile fabrics specially ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sidewalk
A sidewalk (North American English), pavement (British English), footpath in Australia, India, New Zealand and Ireland, or footway, is a path along the side of a street, street, highway, terminals. Usually constructed of concrete, pavers, brick, stone, or asphalt, it is designed for pedestrians. A sidewalk is normally higher than the carriageway, roadway, and separated from it by a kerb (spelled "curb" in North America). There may also be a Road verge, planted strip between the sidewalk and the roadway and between the roadway and the adjacent land. In some places, the same term may also be used for a paved path, trail or footpath that is not next to a road, for example, a path through a park. Terminology The term "sidewalk" is preferred in most of North America. The term "pavement" is more common in the United Kingdom and other members of the Commonwealth of Nations, as well as parts of the Mid-Atlantic United States such as Philadelphia and parts of New Jersey. Many Commonwea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weep Hole
A weep, a weep hole, or a weep-brick is a small opening that allows water to drain from within an assembly. Weeps are located at the bottom of the object to allow for drainage; the weep hole must be sized adequately to overcome surface tension. Weeps may also be necessary in a retaining wall, so water can escape from the retained earth, thus lessening the hydrostatic load on the wall and preventing damage to the wall from the excess water weight and possible moisture damage from freeze/thaw cycles. In such cases the weeps may consist of a plastic, clay or metal pipe extending through the wall to a layer of porous backfill. Typically, weeps are arranged to direct water which may have entered an assembly from outside, back to the outside. Weeps may also be found in metal windows and glazed curtain walls to permit interstitial condensation to escape. Automotive water pumps have weep holes to protect the bearings by letting out water that leaks past the seal. Masonry In building ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pier (architecture)
A pier, in architecture, is an upright support for a structure or superstructure such as an arch or bridge. Sections of structural walls between openings (bays) can function as piers. External or free-standing walls may have piers at the ends or on corners. Description The simplest cross section of the pier is square, or rectangular, but other shapes are also common. In medieval architecture, massive circular supports called drum piers, cruciform (cross-shaped) piers, and compound piers are common architectural elements. Columns are a similar upright support, but stand on a round base. In buildings with a sequence of bays between piers, each opening (window or door) between two piers is considered a single bay. Bridge piers Single-span bridges have abutments at each end that support the weight of the bridge and serve as retaining walls to resist lateral movement of the earthen fill of the bridge approach. Multi-span bridges require piers to support the ends of spans betwe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abutment
An abutment is the substructure at the ends of a bridge span or dam supporting its superstructure. Single-span bridges have abutments at each end which provide vertical and lateral support for the span, as well as acting as retaining walls to resist lateral movement of the earthen fill of the bridge approach. Multi-span bridges require piers to support ends of spans unsupported by abutments. Dam abutments are generally the sides of a valley or gorge, but may be artificial in order to support arch dams such as Kurobe Dam in Japan. The civil engineering term may also refer to the structure supporting one side of an arch, or masonry used to resist the lateral forces of a vault.Pevsner, N. (1970) ''Cornwall''; 2nd ed. Harmondsworth: Penguin; p. 245 The impost or abacus of a column in classical architecture may also serve as an abutment to an arch. The word derives from the verb "abut", meaning to "touch by means of a mutual border". Use in engineering An abutment may be us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deep Foundation
A deep foundation is a type of foundation that transfers building loads to the earth farther down from the surface than a shallow foundation does to a subsurface layer or a range of depths. A pile or piling is a vertical structural element of a deep foundation, driven or drilled deep into the ground at the building site. There are many reasons that a geotechnical engineer would recommend a deep foundation over a shallow foundation, such as for a skyscraper. Some of the common reasons are very large design loads, a poor soil at shallow depth, or site constraints like property lines. There are different terms used to describe different types of deep foundations including the pile (which is analogous to a pole), the pier (which is analogous to a column), drilled shafts, and caissons. Piles are generally driven into the ground in situ; other deep foundations are typically put in place using excavation and drilling. The naming conventions may vary between engineering discip ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caisson (engineering)
In geotechnical engineering, a caisson ( or ; borrowed from French ''caisson'', from Italian ''cassone'', meaning ''large box'', an augmentative of ''cassa'') is a watertight retaining structure used, for example, to work on the foundations of a bridge pier, for the construction of a concrete dam, or for the repair of ships. Caissons are constructed in such a way that the water can be pumped out, keeping the work environment dry. When piers are being built using an open caisson, and it is not practical to reach suitable soil, friction pilings may be driven to form a suitable sub-foundation. These piles are connected by a foundation pad upon which the column pier is erected. Caisson engineering has been used at least since the 18th century, and was notably used in the construction of the Brooklyn Bridge, which was completed in 1883. Types To install a caisson in place, it is brought down through soft mud until a suitable foundation material is encountered. While bedrock is pref ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Foundation (engineering)
In engineering, a foundation is the element of a structure which connects it to the ground, transferring loads from the structure to the ground. Foundations are generally considered either shallow or deep. Foundation engineering is the application of soil mechanics and rock mechanics (geotechnical engineering) in the design of foundation elements of structures. Purpose Foundations provide the structure's stability from the ground: * To distribute the weight of the structure over a large area in order to avoid overloading the underlying soil (possibly causing unequal settlement). * To anchor the structure against natural forces including earthquakes, floods, droughts, frost heaves, tornadoes and wind. * To provide a level surface for construction. * To anchor the structure deeply into the ground, increasing its stability and preventing overloading. * To prevent lateral movements of the supported structure (in some cases). Requirements of a good foundation The design and the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Span (architecture)
Span is the distance between two intermediate supports for a structure, e.g. a beam (structure), beam or a bridge. A span can be closed by a solid beam or by a rope. The first kind is used for bridges, the second one for power lines, overhead telecommunication lines, some type of Antenna (radio), antennas or for aerial tramways. The span is a significant factor in finding the strength and size of a beam as it determines the maximum bending moment and Deflection (engineering), deflection. The maximum bending moment M_ and deflection \delta_in the pictured beam is found using: :M_ = \frac :\delta_ = \frac = \frac where :q = Uniformly distributed load :L = Length of the beam between two supports (span) :E = Modulus of elasticity :I = Area moment of inertia Note that the maximum bending moment and deflection occur midway between the two supports. From this it follows that if the span is doubled, the maximum moment (and with it the tensile stress, stress) will quadruple, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
