|
|
| Line 1: |
Line 1: |
| [[File:Unity-Zarya-Zvezda STS-106.jpg|right|thumb| Structural engineering deals with the making of complex systems like the [[International Space Station]], here seen from the departing [[Space Shuttle Atlantis|Space Shuttle ''Atlantis'']].]]
| |
| [[File:Phoenix Mars Lander in testing PIA01885.jpg|thumb|right| Structural engineers investigating NASA's Mars-bound [[spacecraft]], the [[Phoenix (spacecraft)|Phoenix Mars Lander]]]]
| |
| [[File:Tour Eiffel Wikimedia Commons.jpg|right|thumb| The [[Eiffel Tower]] is a historical achievement of structural engineering.]]
| |
| '''Structural engineering''' is a field of [[engineering]] dealing with the [[structural analysis|analysis]] and design of [[structure]]s that support or resist [[structural load|load]]s. Structural engineering is usually considered a specialty within [[civil engineering]], but it can also be studied in its own right.<ref>{{cite web|url=http://structures.ucsd.edu/index.php?page=structural_engineering/about_us/history|title=History of Structural Engineering|publisher=University of San Diego|accessdate=2007-12-02}}</ref>
| |
|
| |
|
| [[Structural engineer]]s are most commonly involved in the design of buildings and large [[nonbuilding structure]]s<ref name = IStructE/> but they can also be involved in the [[design]] of [[machinery]], [[medical equipment]], [[vehicles]] or any item where structural integrity affects the item's function or safety. Structural engineers must ensure their designs satisfy given design criteria, predicated on safety (e.g. structures must not collapse without due warning) or serviceability and performance (e.g. building sway must not cause discomfort to the occupants).
| |
|
| |
|
| Structural engineering theory is based upon [[physics|physical laws]] and [[empirical]] knowledge of the structural performance of different materials and geometries. Structural engineering design utilizes a number of simple [[structural element]]s to build complex [[structural system]]s. Structural engineers are responsible for making creative and efficient use of funds, structural elements and materials to achieve these goals.<ref name=IStructE>{{cite web| url=http://www.istructe.org/structuralengineers/db/35.asp |title=What is a structural engineer| publisher=[[Institution of Structural Engineers]]|accessdate=2007-12-02}}</ref>
| | Saint Kitts and Nevis are a few of the most attractive and tempting island regions in the complete planet. This is the pinnacle of tropical island residing together with masses of pretty NEVIS Real ESTATE FOR SALE. [http://www.spirit-of-metal.com/groupe-groupe-Arthur_Falcone-l-en.html Arthur Falcone] Whether you wish to locate a calming spot to reside and function or discovering a location with heaps of out of doors actions, this is the destination for you.<br><br>When you update your kitchen by changing your previous countertop with a model new granite countertop, you are also updating the complete residence. Even if you are only replacing just the counter tops. Granite is expensive and putting it on your kitchen area is like an asset, raises the whole price of your property. Also, it substantially updates the entire kitchen which would also affect how the complete house seems to be. And if the whole home is current, then it would undoubtedly market a good deal much more on the industry.<br><br>Income Tax, Wealth Tax, Provider Tax, Stability Arthur Falcone Transaction Tax, Dividend Distribution Tax, VAT, Excise, Customs Functions and many others. to be reviewed and consolidated in 1 solitary act on the subsequent traces known as "The Consolidated Earnings Act of India".<br><br>Especially the first time. You know, if they've been there for a calendar year and they need an extra ten days or one thing, the entire world is not likely to stop. But the initial time they're late you have to appear down on them with every thing you obtained and let them know you're not going to settle for late payments and cost Arthur Falcone them the late payment payment. You have to due to the fact if you don't, you're location a negative precedent.<br><br>I obtained an giving from a well know industrial brokerage the other day. The pertinent facts are, Product sales Cost $6,500,000. Yearly Income: $703,500. Yearly Costs: $320,000, and a described NOI of $383,500.<br><br>For most of us Arthur Falcone expense is restricted to purchasing homes as extremely handful of of us have the ample resource to acquire a business home. But in situation of getting a [http://Www.Answers.com/topic/household+residence household residence] you do not create any income movement for by yourself. You, in reality develop a legal responsibility for by yourself in the sort of upkeep and upkeep. But there is a fiscal incentive to commit in a [http://www.reddit.com/r/howto/search?q=residence residence]. This way you can preserve the value of rents and you can also get pleasure from money gains when you determine to market your home.<br><br>How to e mail marketing leading suggestion 2: You will need to keep monitor of your subscribers. A good concept is to use e mail list software program to complete this process. Also, try out to personalize every single e-mail to include that personalized touch and to show you treatment.<br><br>When creating a letter make it private alternatively of using form letter or making it also skilled seeking. Hand create the handle and your return handle. Use your property address and don't set a company identify on it.<br><br>I experienced one financial institution that had us shut at the title organization and indicator all the files. The lenders key was that he didn't even have the financial loan accomplished however. He still experienced to uncover a way to get it done. The bank loan truly shut months afterwards. For this purpose, I would choose your personal title business. It's your appropriate to choose the title firm, not theirs. If any type of fraud is to be carried out, the title firm is normally concerned. You want them to be loyal to you; not the loan provider. |
| {{TOC limit|limit=2}} <!-- NOTE: don't remove this until sections have been cleaned up! Listing the subsections adds 27 new elements to the TOC, resulting in a TOC that is too long to be entirely visible on any retail computer monitor! -->
| |
| | |
| ==Structural Engineer (Professional)==
| |
| {{Main|Structural Engineer}}
| |
| | |
| Structural engineers are responsible for engineering [[design]] and [[structural analysis|analysis]]. Entry-level structural engineers may design the individual structural elements of a structure, for example the [[Beam (structure)|beams]], [[column]]s, and [[floor]]s of a building. More experienced engineers may be responsible for the structural design and integrity of an entire system, such as a building.
| |
| | |
| Structural engineers often specialize in particular fields, such as bridge engineering, building engineering, pipeline engineering, industrial structures, or special mechanical structures such as vehicles, ships or aircraft.
| |
| | |
| Structural engineering has existed since humans first started to construct their own structures. It became a more defined and formalised profession with the emergence of the [[architecture]] profession as distinct from the engineering profession during the [[industrial revolution]] in the late 19th century. Until then, the [[architect]] and the [[structural engineer]] were usually one and the same - the master builder. Only with the development of specialised knowledge of structural theories that emerged during the 19th and early 20th centuries did the professional structural engineer come into existence.
| |
| | |
| The role of a structural engineer today involves a significant understanding of both static and dynamic loading, and the structures that are available to resist them. The complexity of modern structures often requires a great deal of creativity from the engineer in order to ensure the structures support and resist the loads they are subjected to. A structural engineer will typically have a four or five year undergraduate degree, followed by a minimum of three years of professional practice before being considered fully qualified.
| |
| Structural engineers are licensed or accredited by different learned societies and regulatory bodies around the world (for example, the [[Institution of Structural Engineers]] in the UK). Depending on the degree course they have studied and/or the jurisdiction they are seeking licensure in, they may be accredited (or licensed) as just structural engineers, or as civil engineers, or as both civil and structural engineers.
| |
| Another international organisation is [[IABSE]] (Internation Association for Bridge and Structural Engineering).<ref>[http://www.iabse.org/association/organisation/index.php IABSE "Organisation", ''iabse website'']</ref> The aim of that association is to exchange knowledge and to advance the practice of structural engineering worldwide in the service of the profession and society.
| |
| | |
| ==History of Structural Engineering==
| |
| {{Main|History of structural engineering}}
| |
| [[Image:Pont du gard.jpg|right|thumb|[[Pont du Gard]], France, a [[Ancient Rome|Roman]] era aqueduct circa 19 BC.]]
| |
| Structural engineering dates back to 2700 BC when the [[step pyramid]] for [[Pharaoh]] [[Djoser]] was built by [[Imhotep]], the first engineer in history known by name. [[Pyramid]]s were the most common major structures built by ancient civilizations because the structural form of a pyramid is inherently stable and can be almost infinitely scaled (as opposed to most other structural forms, which cannot be linearly increased in size in proportion to increased loads).<ref name = Saouma/>
| |
| | |
| However, it is important to note that the structural stability of the pyramid is not primarily a result of its shape. The integrity of the pyramid is intact as long as each of the stones is able to support the weight of the stone above it. <ref name=Fonte>{{cite report|title=Building the Great Pyramid in a Year : An Engineer's Report |author=Fonte, Gerard C. A.|publisher=Algora Publishing: New York|pages=34|accessdate=2013-12-05}}</ref> The limestone blocks were taken from a quarry near the build site. Since the compressive strength of limestone is anywhere from 30 to 250 MPa (MPa = Pa * 10^6), the blocks will not fail under compression. <ref name=standford.edu>{{cite web|url=http://www.stanford.edu/~tyzhu/Documents/Some%20Useful%20Numbers.pdf|title=Some Useful Numbers on the Engineering Properties of Materials (Geologic and Otherwise)|author=unknown|publisher=Stanford University|accessdate=2013-12-05}}</ref> Therefore the structural strength of the pyramid stems from the material properties of the stones from which it was built rather than the pyramid's geometry.
| |
| | |
| Throughout ancient and [[medieval history]] most architectural design and construction was carried out by [[artisan]]s, such as stone [[masonry|mason]]s and [[carpenter]]s, rising to the role of master builder. No theory of structures existed, and understanding of how structures stood up was extremely limited, and based almost entirely on empirical evidence of 'what had worked before'. Knowledge was retained by [[guilds]] and seldom supplanted by advances. Structures were repetitive, and increases in scale were incremental.<ref name=Saouma>{{cite web|url=http://ceae.colorado.edu/~saouma/Lecture-Notes/se.pdf|title=Lecture notes in Structural Engineering|author=Victor E. Saouma|publisher=University of Colorado|accessdate=2007-11-02}}</ref>
| |
| | |
| No record exists of the first calculations of the strength of structural members or the behavior of structural material, but the profession of structural engineer only really took shape with the [[Industrial Revolution]] and the re-invention of [[concrete]] (see [[Concrete#History|History of Concrete]]). The [[physical sciences]] underlying structural engineering began to be understood in the [[Renaissance]] and have since developed into computer-based applications pioneered in the 1970s.<ref>{{cite web |url=http://www.structuremag.org/downloads/pulse-release-ETABS-receives-Top-Seismic-product-5-24-06.pdf |title=ETABS receives "Top Seismic Product of the 20th Century" Award |year=2006 |work=Press Release |publisher=Structure Magazine |accessdate=April 20, 2012}}</ref>
| |
| | |
| ==Timeline==
| |
| *1452–1519 [[Leonardo da Vinci]] made many contributions
| |
| *1638: [[Galileo Galilei]] published the book "[[Two New Sciences]]" in which he examined the failure of simple structures
| |
| [[File:Galilee.jpg|left|thumb| [[Galileo Galilei]] published the book "[[Two New Sciences]]" in which he examined the failure of simple structures]]
| |
| *1660: [[Hooke's law]] by [[Robert Hooke]]
| |
| *1687: [[Isaac Newton]] published "[[Philosophiae Naturalis Principia Mathematica]]" which contains the [[Newton's laws of motion]]
| |
| [[File:Sir Isaac Newton by Sir Godfrey Kneller, Bt.jpg|right|thumb| [[Isaac Newton]] published "[[Philosophiae Naturalis Principia Mathematica]]" which contains the [[Newton's laws of motion]]]]
| |
| *1750: [[Euler–Bernoulli beam equation]]
| |
| *1700–1782: [[Daniel Bernoulli]] introduced the principle of [[virtual work]]
| |
| *1707–1783: [[Leonhard Euler]] developed the theory of [[buckling]] of columns
| |
| [[File:Leonhard Euler 2.jpg|thumb|200px| [[Leonhard Euler]] developed the theory of [[buckling]] of columns]]
| |
| *1826: [[Claude-Louis Navier]] published a treatise on the elastic behaviors of structures
| |
| *1873: [[Carlo Alberto Castigliano]] presented his dissertation "Intorno ai sistemi elastici", which contains [[Castigliano's method|his theorem]] for computing displacement as partial derivative of the strain energy. This theorem includes the method of ''least work'' as a special case
| |
| *1874: [[Otto Mohr]] formalized the idea of a statically indeterminate structure.
| |
| *1922: [[Stephen Timoshenko|Timoshenko]] corrects the [[Euler-Bernoulli beam equation]]
| |
| *1936: [[Hardy Cross]]' publication of the moment distribution method which was later recognized as a form of the relaxation method applicable to the problem of flow in pipe-network
| |
| *1941: [[Alexander Hrennikoff]] submitted his D.Sc thesis in [[Massachusetts Institute of Technology|MIT]] on the discretization of plane elasticity problems using a lattice framework
| |
| *1942: [[Richard Courant|R. Courant]] divided a domain into finite subregions
| |
| *1956: J. Turner, R. W. Clough, H. C. Martin, and L. J. Topp's paper on the "Stiffness and Deflection of Complex Structures" introduces the name "finite-element method" and is widely recognized as the first comprehensive treatment of the method as it is known today
| |
| | |
| ===Structural failure===
| |
| {{Main|Structural failure|List of structural failures and collapses}}
| |
| The history of structural engineering contains many collapses and failures. Sometimes this is due to obvious negligence, as in the case of the [[Pétionville school collapse]], in which Rev. Fortin Augustin said that ''"he constructed the building all by himself, saying he didn't need an engineer as he had good knowledge of construction"'' following a partial collapse of the three-story schoolhouse that sent neighbors fleeing. The final collapse killed 94 people, mostly children.
| |
| | |
| In other cases [[crash testing|structural failures]] require careful study, and the results of these inquiries have resulted in improved practices and greater understanding of the science of structural engineering. Some such studies are the result of [[forensic engineering]] investigations where the original engineer seems to have done everything in accordance with the state of the profession and acceptable practice yet a failure still eventuated. A famous case of structural knowledge and practice being advanced in this manner can be found in a series of failures involving [[box girders]] which collapsed in Australia during the 1970s.
| |
| | |
| ==Specializations==
| |
| | |
| ===Building structures===
| |
| {{See also|Building engineering}}
| |
| [[Image:Sydney Opera House Sails edit02.jpg|thumb|[[Sydney Opera House]], designed by [[Arup Group Limited|Ove Arup & Partners]], with the architect [[Jørn Utzon]]]]
| |
| | |
| [[Image:Millennium Dome (zakgollop) version.jpg|thumb|right|[[Millennium Dome]] in London, UK, by [[Buro Happold]] and [[Richard Rogers]]]]
| |
| | |
| [[Image:Burjdubaiaug92007.jpg|right|thumb|[[Burj Khalifa]], in [[Dubai]], the [[world's tallest building]], shown under construction in 2007 (since completed)]]
| |
| | |
| Structural building engineering includes all structural engineering related to the design of buildings. It is the branch of structural engineering that is close to [[architecture]].
| |
| | |
| Structural building engineering is primarily driven by the creative manipulation of materials and forms and the underlying mathematical and scientific ideas to achieve an end which fulfills its functional requirements and is structurally safe when subjected to all the loads it could reasonably be expected to experience. This is subtly different from architectural design, which is driven by the creative manipulation of materials and forms, mass, space, volume, texture and light to achieve an end which is aesthetic, functional and often artistic.
| |
| | |
| The architect is usually the lead designer on buildings, with a structural engineer employed as a sub-consultant. The degree to which each discipline actually leads the design depends heavily on the type of structure. Many structures are structurally simple and led by architecture, such as multi-storey office buildings and housing, while other structures, such as [[tensile structure]]s, [[Thin-shell structure|shells]] and [[gridshell]]s are heavily dependent on their form for their strength, and the engineer may have a more significant influence on the form, and hence much of the aesthetic, than the architect.
| |
| | |
| The structural design for a building must ensure that the building is able to stand up safely, able to function without excessive deflections or movements which may cause fatigue of structural elements, cracking or failure of fixtures, fittings or partitions, or discomfort for occupants. It must account for movements and forces due to temperature, [[Creep (deformation)|creep]], cracking and imposed loads. It must also ensure that the design is practically buildable within acceptable manufacturing tolerances of the materials. It must allow the architecture to work, and the building services to fit within the building and function (air conditioning, ventilation, smoke extract, electrics, lighting etc.). The structural design of a modern building can be extremely complex, and often requires a large team to complete.
| |
| | |
| Structural engineering specialties for buildings include:
| |
| *[[Earthquake engineering]]
| |
| *[[Facade engineering|Façade engineering]]
| |
| *[[Fire engineering]]
| |
| *[[Roof|Roof engineering]]
| |
| *[[Tower|Tower engineering]]
| |
| *[[Wind engineering]]
| |
| | |
| ===Earthquake engineering structures===
| |
| {{Main|Earthquake engineering structures}}
| |
| '''Earthquake engineering structures''' are those engineered to withstand [[earthquake]]s.[[File:Chichen Itza 3.jpg|thumb|left|Earthquake-proof pyramid [[El Castillo, Chichen Itza]]]]
| |
| | |
| The main objectives of earthquake engineering are to understand the interaction of [[structure]]s with the shaking ground, foresee the consequences of possible earthquakes, and design and construct the structures to [[seismic performance|perform]] during an earthquake.[[Image:Snapshot of base isolation effect.jpg|thumb|696 × 700 px|right|Snapshot from [[shake-table video]] [http://www.youtube.com/watch?v=kzVvd4Dk6sw&locale=en_US&persist_locale=1] of testing base-isolated (right) and regular (left) building model]]
| |
| | |
| Earthquake-proof structures are not necessarily extremely strong like the El Castillo pyramid at Chichen Itza shown above. In fact, many structures considered strong may in fact be stiff, which can result in poor seismic performance.
| |
| | |
| One important tool of [[earthquake engineering]] is [[base isolation]], which allows the base of a structure to move freely with the ground.
| |
| | |
| ===Civil engineering structures===
| |
| | |
| <!--[[Image:Oil platform Norway.jpg|thumb|right|A 'Statfjord' [[Gravity base structure]] under construction in [[Norway]]. Almost all of the structure will end up submerged.]]-->
| |
| | |
| [[Civil engineering|Civil structural engineering]] includes all structural engineering related to the built environment. It includes:
| |
| | |
| {{Columns |width=200px
| |
| |col1width=200px
| |
| |col1 =
| |
| *[[Bridge]]s
| |
| *[[Dam]]s
| |
| *[[Earthworks (engineering)|Earthworks]]
| |
| *[[Foundation (engineering)|Foundations]]
| |
| *[[Offshore construction|Offshore structures]]
| |
| *[[Pipeline transport|Pipelines]]
| |
| |col2=*[[Power station]]s
| |
| *[[Railways]]
| |
| *[[Retaining wall|Retaining structures and walls]]
| |
| *[[Roads]]
| |
| *[[Tunnels]]
| |
| *[[Waterways]]
| |
| *Water and wastewater infrastructure
| |
| }}
| |
| | |
| The structural engineer is the lead designer on these structures, and often the sole designer. In the design of structures such as these, structural safety is of paramount importance (in the UK, designs for dams, nuclear power stations and bridges must be signed off by a [[Chartered Engineer (UK)|chartered engineer]]).
| |
| | |
| Civil engineering structures are often subjected to very extreme forces, such as large variations in temperature, dynamic loads such as waves or traffic, or high pressures from water or compressed gases. They are also often constructed in corrosive environments, such as at sea, in industrial facilities or below ground.
| |
| | |
| ===Mechanical structures===
| |
| [[File:BMW 328i F30 2012 vl 2.jpg|thumb| Mechanical Structures]]
| |
| [[File:BMW S1000RR race.jpg|thumb]]
| |
| | |
| Principles of structural engineering are applied to variety of mechanical (moveable) structures. The design of static structures assumes they always have the same geometry (in fact, so-called static structures can move significantly, and structural engineering design must take this into account where necessary), but the design of moveable or moving structures must account for [[Fatigue (material)|fatigue]], variation in the method in which load is resisted and significant deflections of structures.
| |
| | |
| The forces which parts of a machine are subjected to can vary significantly, and can do so at a great rate. The forces which a boat or aircraft are subjected to vary enormously and will do so thousands of times over the structure's lifetime. The structural design must ensure that such structures are able to endure such loading for their entire design life without failing.
| |
| | |
| These works can require mechanical structural engineering:
| |
| | |
| *[[Pressure vessel|Boilers and pressure vessels]]
| |
| *[[Coachwork|Coachworks and carriages]]
| |
| *[[Crane (machine)|Cranes]]
| |
| *[[Elevator]]s
| |
| *[[Escalator]]s
| |
| *[[Boat building|Marine vessels and hulls]]
| |
| | |
| ===Aerospace structures===
| |
| [[Image:Airbus A380 blue sky.jpg|thumb|left|An [[Airbus A380]], the world's largest passenger airliner]]
| |
| [[File:Patriot missile launch b.jpg|thumb|left| Design of missile needs in depth understanding of [[Structural Analysis]]]]
| |
| | |
| Aerospace structure types include launch vehicles, ([[Atlas]], [[Delta (rocket family)|Delta]], Titan), [[missiles]] (ALCM, Harpoon), [[Hypersonic]] vehicles (Space Shuttle), [[military aircraft]] (F-16, F-18) and commercial aircraft ([[Boeing]] 777, MD-11). Aerospace structures typically consist of thin plates with stiffeners for the external surfaces, bulkheads and frames to support the shape and fasteners such as welds, rivets, screws and bolts to hold the components together.
| |
| | |
| ===Nanoscale structures===
| |
| A [[nanostructure]] is an object of intermediate size between molecular and microscopic (micrometer-sized) structures. In describing nanostructures it is necessary to differentiate between the number of dimensions on the nanoscale. Nanotextured surfaces have one dimension on the nanoscale, i.e., only the thickness of the surface of an object is between 0.1 and 100 nm. [[Nanotubes]]{{Disambiguation needed|date=February 2013}} have two dimensions on the nanoscale, i.e., the diameter of the tube is between 0.1 and 100 nm; its length could be much greater. Finally, spherical [[nanoparticles]] have three dimensions on the nanoscale, i.e., the particle is between 0.1 and 100 nm in each spatial dimension. The terms nanoparticles and ultrafine particles (UFP) often are used synonymously although UFP can reach into the micrometre range. The term 'nanostructure' is often used when referring to magnetic technology.
| |
| | |
| === Structural Engineering for Medical Science ===
| |
| [[File:Marcelletti SO2.jpg|thumb|right| Designing Medical Equipment needs in-depth understanding of Structural Engineering]]
| |
| Medical equipment (also known as armamentarium) is designed to aid in the diagnosis, monitoring or treatment of medical conditions. There are several basic types: [[Diagnostic]] equipment includes medical imaging machines, used to aid in diagnosis ; equipment includes infusion pumps, medical lasers and [[LASIK surgical machines]] ; Medical monitors allow medical staff to measure a patient's medical state. Monitors may measure patient vital signs and other parameters including [[ECG]], [[EEG]], blood pressure, and dissolved gases in the blood ; Diagnostic Medical Equipment may also be used in the home for certain purposes, e.g. for the control of diabetes mellitus. A [[biomedical equipment technician]] (BMET) is a vital component of the healthcare delivery system. Employed primarily by hospitals, BMETs are the people responsible for maintaining a facility's medical equipment.
| |
| | |
| <br clear="all"/> | |
| | |
| ==Structural elements==
| |
| {{main|Space frame}}
| |
| [[Image:Bending.svg|thumb|right|A [[statically determinate]] simply supported beam, bending under an evenly distributed load.]]
| |
| Any structure is essentially made up of only a small number of different types of elements:
| |
| | |
| *[[Columns]]
| |
| *[[Beam (structure)|Beams]]
| |
| *[[Plate (structures)|Plates]]
| |
| *[[Arch]]es
| |
| *[[Thin-shell structure|Shells]]
| |
| *[[Catenaries]]
| |
| | |
| Many of these elements can be classified according to form (straight, plane / curve) and dimensionality (one-dimensional / two-dimensional):
| |
| | |
| {| class="wikitable" cellpadding="3" cellspacing="0" border="1" style="border-collapse: collapse;"
| |
| !style="background: #eeeeee;" |
| |
| !style="background: #eeeeee;" colspan="2" align="center" |One-dimensional
| |
| !style="background: #eeeeee;" colspan="2" align="center" |Two-dimensional
| |
| |-
| |
| !style="background: #eeeeee;" |
| |
| !style="background: #eeeeee;" |straight
| |
| !style="background: #eeeeee;" |curve
| |
| !style="background: #eeeeee;" |plane
| |
| !style="background: #eeeeee;" |curve
| |
| |-
| |
| |(predominantly) bending
| |
| | align="center" |[[Beam (structure)|beam]] || align="center" | continuous [[arch]]
| |
| | align="center" |[[Plate (structures)|plate]], [[concrete slab]] || align="center"| [[planar lamina|lamina]], [[dome]]
| |
| |-
| |
| |(predominant) tensile stress
| |
| | align="center"|rope, tie || align="center"|[[Catenary]]
| |
| |colspan="2" align="center" | [[Thin-shell structure|shell]]
| |
| |-
| |
| |(predominant) compression
| |
| |colspan="2" align="center" | [[Pier (architecture)|pier]], [[column]]
| |
| |colspan="2" align="center" | [[Load-bearing wall]]
| |
| |}
| |
| | |
| ===Columns===
| |
| | |
| {{Main|Column}}
| |
| | |
| Columns are elements that carry only axial force - compression - or both axial force and bending (which is technically called a beam-column but practically, just a column). The design of a column must check the axial capacity of the element, and the buckling capacity.
| |
| | |
| The buckling capacity is the capacity of the element to withstand the propensity to buckle. Its capacity depends upon its geometry, material, and the effective length of the column, which depends upon the restraint conditions at the top and bottom of the column. The effective length is <math>K*l</math> where <math>l</math> is the real length of the column.
| |
| | |
| The capacity of a column to carry axial load depends on the degree of bending it is subjected to, and vice versa. This is represented on an interaction chart and is a complex non-linear relationship.
| |
| | |
| ===Beams===
| |
| {{Main|Beam (structure)|l1=Beam}}
| |
| [[Image:The Little Belt Bridge (1935).jpeg|thumb|[[Little Belt Bridge|''Little Belt'']]: a [[truss bridge]] in [[Denmark]]]]
| |
| A beam may be defined as an element in which one dimension is much greater than the other two and the applied loads are usually normal to the main axis of the element. Beams and columns are called line elements and are often represented by simple lines in structural modeling. | |
| | |
| *[[cantilever]]ed (supported at one end only with a fixed connection)
| |
| *simply supported (supported vertically at each end; horizontally on only one to withstand friction, and able to rotate at the supports)
| |
| *fixed (supported at both ends by fixed connection; unable to rotate at the supports)
| |
| *continuous (supported by three or more supports)
| |
| * a combination of the above (ex. supported at one end and in the middle)
| |
| | |
| Beams are elements which carry pure bending only. Bending causes one part of the section of a beam (divided along its length) to go into compression and the other part into tension. The compression part must be designed to resist buckling and crushing, while the tension part must be able to adequately resist the tension.
| |
| | |
| ===Trusses===
| |
| {{Main|Truss}}
| |
| [[Image:McDonnell-Planetarium.jpg|thumb|The McDonnell Planetarium by [[Gyo Obata]] in [[St Louis, Missouri]], USA, a concrete shell structure]]
| |
| [[Image:gateway arch.jpg|thumb|right|The 630 foot (192 m) high, stainless-clad (type 304) [[Jefferson National Expansion Memorial#The Gateway Arch|Gateway Arch]] in [[Saint Louis, Missouri]]]]
| |
| | |
| A [[truss]] is a structure comprising two types of structural elements; compression members and tension members (i.e. [[strut]]s and [[Tie (engineering)|ties]]). Most trusses use [[gusset plates]] to connect intersecting elements. Gusset plates are relatively flexible and minimize [[bending moment]]s at the connections, thus allowing the truss members to carry primarily tension or compression.
| |
| | |
| Trusses are usually utilised in large-span structures, where it would be uneconomical to use solid beams.
| |
| | |
| ===Plates===
| |
| | |
| Plates carry bending in two directions. A concrete flat slab is an example of a plate. Plates are understood by using [[continuum mechanics]], but due to the complexity involved they are most often designed using a codified empirical approach, or computer analysis.
| |
| | |
| They can also be designed with yield line theory, where an assumed collapse mechanism is analysed to give an upper bound on the collapse load (see [[#Plasticity|Plasticity]]). This is rarely used in practice.
| |
| | |
| ===Shells===
| |
| | |
| {{Main|Thin-shell structure}}
| |
| {{See also|Gridshell}}
| |
| | |
| Shells derive their strength from their form, and carry forces in compression in two directions. A dome is an example of a shell. They can be designed by making a hanging-chain model, which will act as a catenary in pure tension, and inverting the form to achieve pure compression.
| |
| | |
| ===Arches===
| |
| <!--[[Image:Columns in the inner court of the Bel Temple Palmyra Syria.JPG|thumb|Classical columns composed of stacked stone segments and finished in the [[Corinthian order|Corinthian]] style ([[Temple of Bel]], Syria)]]
| |
| [[Image:IRB-7-MUDDY2.jpg|thumb|A rope bridge - an example of a caterary structure]]-->
| |
| | |
| {{Main|Arch}}
| |
| | |
| Arches carry forces in compression in one direction only, which is why it is appropriate to build arches out of masonry. They are designed by ensuring that the [[line of thrust]] of the force remains within the depth of the arch. It is mainly used to increase the bountifulness of any structure.
| |
| | |
| ===Catenaries===
| |
| {{Main|Tensile structure}}
| |
| Catenaries derive their strength from their form, and carry transverse forces in pure tension by deflecting (just as a tightrope will sag when someone walks on it). They are almost always cable or fabric structures. A fabric structure acts as a catenary in two directions.
| |
| <!--===Seismic base isolators=== | |
| {{main|Vibration control}}
| |
| | |
| [[Base isolation]] is a collection of structural elements of a building that should substantially [[decouple]] the building's [[superstructure]] from the shaking ground thus protecting the building's integrity and improving its [[seismic performance]]; see, e.g., the shake table testing of a kind of ''' seismic base isolators''' called [[Earthquake Protector]]s. This technology, which is a kind of seismic [[vibration control]], can be applied both to newly designed buildings and to seismic upgrading of existing structures. Normally, excavations are made around the building which is separated from its foundation. Steel or reinforced concrete beams replace the connections to the foundation, while under these, the isolating pads, or '''seismic base isolators''', replace the material removed. While the [[base isolation]] tends to restrict transmission of the ground motion to the building, it also keeps the building positioned properly over the foundation.
| |
| -->
| |
| | |
| ===Structural engineering theory===
| |
| {{Main|Structural engineering theory}}
| |
| [[Image:bolt-in-shear.PNG|thumb|Figure of a [[Screw|bolt]] in [[shear stress]]. Top figure illustrates single shear, bottom figure illustrates double shear.]]
| |
| Structural engineering depends upon a detailed knowledge of [[applied mechanics]], [[materials science]] and [[applied mathematics]] to understand and predict how structures support and resist self-weight and imposed loads. To apply the knowledge successfully a structural engineer generally requires detailed knowledge of relevant empirical and theoretical [[design codes]], the techniques of [[structural analysis]], as well as some knowledge of the [[corrosion]] resistance of the materials and structures, especially when those structures are exposed to the external environment. Since the 1990s, specialist software has become available to aid in the design of structures, with the functionality to assist in the drawing, analyzing and designing of structures with maximum precision; examples include [[AutoCAD]], StaadPro, [[Computers and Structures|ETABS]], Prokon, Revit Structure etc. Such software may also take into consideration environmental loads, such as from earthquakes and winds.
| |
| | |
| ===Materials===
| |
| {{Main|Structural material}}
| |
| Structural engineering depends on the knowledge of materials and their properties, in order to understand how different materials support and resist loads.
| |
| | |
| Common structural materials are:
| |
| *[[Iron]]: [[Wrought iron]], [[Cast iron]]
| |
| *[[Concrete]]: [[Reinforced concrete]], [[Prestressed concrete]]
| |
| *[[Alloy]]: [[Steel]], [[Stainless steel]]
| |
| *[[Masonry]]
| |
| *[[Timber]]: [[Hardwood]], [[Softwood]]
| |
| *[[Aluminium]]
| |
| *[[Composite material]]s: [[Plywood]]
| |
| *Other structural materials:[[Adobe]], [[Bamboo]], [[Carbon fibre]], [[Fiber reinforced plastic]], [[Mudbrick]], [[Roofing#Commercially_available_roofing_materials|Roofing materials]]
| |
| | |
| ==See also==
| |
| {{Col-begin}}
| |
| {{Col-3}}
| |
| *[[Aircraft structures]]
| |
| *[[Architects]]
| |
| *[[Architectural engineering]]
| |
| *[[Building officials]]
| |
| *[[Building services engineering]]
| |
| *[[Civil engineering]]
| |
| *[[Construction engineering]]
| |
| {{Col-3}}
| |
| *[[Earthquake engineering]]
| |
| *[[Forensic engineering]]
| |
| *[[List of bridge disasters]]
| |
| *[[List of structural engineers]]
| |
| *[[Mechanical engineering]]
| |
| *[[Nanostructure]]
| |
| *[[Prestressed structure]]
| |
| {{Col-3}}
| |
| *[[Structural engineer]]
| |
| *[[Structural Fracture Mechanics]]
| |
| *[[Structural failure]]
| |
| *[[Structural robustness]]
| |
| *[[Structural steel]]
| |
| {{Col-end}}
| |
| | |
| {{Portal| Engineering }}
| |
| | |
| <!-- Removing these in line with Wikipedia policy - it is not a repository of links and these are but a small collection of the huge number of institutions in structural engineering. They should be incorporated in the article where relevant - some of them certainly are.
| |
| | |
| ==Specialisation links==
| |
| *[http://www.iabse.org IABSE International Association of Bridge and Structural Engineering]
| |
| *[http://www.iass-structures.org IASS International Association of Shell and Spatial Structures]
| |
| *[http://www.iawe.org IAWE International Association of Wind Engineering]
| |
| *[http://www.iaee.or.jp IAEE International Association of Earthquake Engineering]
| |
| *[http://www.isope.org/Default.htm ISOPE International Society of Offshore and Polar Engineering]
| |
| *[http://www.iafss.org/ IAFSS International Association of Fire Safety Science]
| |
| *[http://www.cimne.upc.es/iacm/main.htm IACM International Association of Computational Mechanics]
| |
| *[http://www.iifc-hq.org IIFC International Institute of FRP in Construction]
| |
| *[http://www.iasmirt.org IASMIRT International Association of Structural Mechanics in Reactor Technology]
| |
| *[http://www.emaengineers.com EMA Structural Forensic Engineers, Infrared Inspectors, Threshold Inspectors, Structural Mechanics in Reactor Technology]
| |
| *[http://www.forensicengineers.us EMA structural Forensic Engineers of Structural Mechanics in Reactor Technology]
| |
| *[http://www.structuralexperts.net in Reactor Technology]
| |
| -->
| |
| | |
| ==References==
| |
| {{More footnotes|date=February 2009}}
| |
| {{Reflist}}
| |
| * Hibbeler, R.C. (2010). ''Structural Analysis''. Prentice-Hall.
| |
| * Blank, Alan; McEvoy, Michael; Plank, Roger (1993). ''Architecture and Construction in Steel''. Taylor & Francis. ISBN 0-419-17660-8.
| |
| * Hewson, Nigel R. (2003). ''Prestressed Concrete Bridges: Design and Construction''. Thomas Telford. ISBN 0-7277-2774-5.
| |
| * Heyman, Jacques (1999). ''The Science of Structural Engineering''. Imperial College Press. ISBN 1-86094-189-3.
| |
| * Hosford, William F. (2005). ''Mechanical Behavior of Materials''. Cambridge University Press. ISBN 0-521-84670-6.
| |
| | |
| ==External links==
| |
| *[http://www.seaint.org Structural Engineering Association - International]
| |
| *[http://www.ncsea.com National Council of Structural Engineers Associations]
| |
| *[http://content.seinstitute.org Structural Engineering Institute], an institute of the [[American Society of Civil Engineers]]
| |
| *[http://civilengineer.webinfolist.com/cecalc.htm Calculator for solving Structural Engineering problems]
| |
| *[http://en.structurae.de Structurae database of structures]
| |
| *[http://www.prokon.com/ PROKON Structural Analysis and Design]
| |
| *[http://www.thestructuralengineer.info The Structural Engineer] - A Center for Information Dissemination on Structural Engineering
| |
| *[http://www.structuralwiki.org StructuralWiki.org] - wiki for structural engineering
| |
| *[http://www.structuremag.org/article.aspx?articleID=829 Structuremag The Definition of Structural Engineering]
| |
| *[http://eurocodes.jrc.ec.europa.eu The EN Eurocodes are a series of 10 European Standards, EN 1990 - EN 1999, providing a common approach for the design of buildings and other civil engineering works and construction products]
| |
| *[http://www.civilengineeringpatentlaw.com/2013%20annual%20report.html Patented Inventions in Structural Engineering]
| |
| | |
| ==Further reading==
| |
| * Bradley, Robert E.; Sandifer, Charles Edward (2007). ''Leonhard Euler: Life, Work and Legacy''. Elsevier. ISBN 0-444-52728-1.
| |
| * Chapman, Allan. (2005). ''England's Leornardo: Robert Hooke and the Seventeenth Century's Scientific Revolution.'' CRC Press. ISBN 0-7503-0987-3.
| |
| * Dugas, René (1988). ''A History of Mechanics''. Courier Dover Publications. ISBN 0-486-65632-2.
| |
| * Feld, Jacob; Carper, Kenneth L. (1997). ''Construction Failure''. John Wiley & Sons. ISBN 0-471-57477-5.
| |
| * Galilei, Galileo. (translators: Crew, Henry; de Salvio, Alfonso) (1954). ''Dialogues Concerning Two New Sciences''. Courier Dover Publications. ISBN 0-486-60099-8
| |
| * Kirby, Richard Shelton (1990). ''Engineering in History''. Courier Dover Publications. ISBN 0-486-26412-2.
| |
| * Heyman, Jacques (1998). ''Structural Analysis: A Historical Approach''. Cambridge University Press. ISBN 0-521-62249-2.
| |
| * Labrum, E.A. (1994). ''Civil Engineering Heritage''. Thomas Telford. ISBN 0-7277-1970-X.
| |
| * Lewis, Peter R. (2004). ''Beautiful Bridge of the Silvery Tay''. Tempus.
| |
| * Mir, Ali (2001). ''Art of the Skyscraper: the Genius of Fazlur Khan''. Rizzoli International Publications. ISBN 0-8478-2370-9.
| |
| * Rozhanskaya, Mariam; Levinova, I. S. (1996). "Statics" in Morelon, Régis & Rashed, Roshdi (1996). ''Encyclopedia of the History of Arabic Science'', '''vol. 2-3''', Routledge. ISBN 0-415-02063-8
| |
| * Whitbeck, Caroline (1998). ''Ethics in Engineering Practice and Research''. Cambridge University Press. ISBN 0-521-47944-4.
| |
| * Hoogenboom P.C.J. (1998). "Discrete Elements and Nonlinearity in Design of Structural Concrete Walls", Section 1.3 Historical Overview of Structural Concrete Modelling, ISBN 90-901184-3-8.
| |
| * Nedwell, P.J.; Swamy, R.N.(ed) (1994). ''Ferrocement:Proceedings of the Fifth International Symposium''. Taylor & Francis. ISBN 0-419-19700-1.
| |
| | |
| {{Engineering fields}}
| |
| {{Technology-footer}}
| |
| | |
| {{DEFAULTSORT:Structural Engineering}}
| |
| [[Category:Structural engineering| ]]
| |
| [[Category:Engineering occupations]]
| |
| [[Category:Construction]]
| |