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60-582: Malaccamax is a naval architecture term for the largest tonnage of ship capable of fitting through the 25-metre-deep (82 ft) Strait of Malacca . Bulk carriers and supertankers have been built to this tonnage, and the term is chosen for very large crude carriers (VLCC). They can transport oil from Arabia to China. A typical Malaccamax tanker can have a maximum length of 333 m (1,093 ft), beam of 60 m (197 ft), draught of 20.5 m (67.3 ft), and tonnage of 300,000 DWT . Similar terms Panamax , Suezmax and Seawaymax are used for

120-443: A 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. The forces which parts of a machine are subjected to can vary significantly and can do so at

180-741: 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. A truss is a structure comprising members and connection points or nodes. When members are connected at nodes and forces are applied at nodes members can act in tension or compression. Members acting in compression are referred to as compression members or struts while members acting in tension are referred to as tension members or ties . Most trusses use gusset plates to connect intersecting elements. Gusset plates are relatively flexible and unable to transfer bending moments . The connection

240-708: 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

300-634: 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 can endure such loading for their entire design life without failing. These works can require mechanical structural engineering: Aerospace structure types include launch vehicles, ( Atlas , 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

360-406: A means of transportation on water . The principal elements of naval architecture are detailed in the following sections. Hydrostatics concerns the conditions to which the vessel is subjected while at rest in water and to its ability to remain afloat. This involves computing buoyancy , displacement , and other hydrostatic properties such as trim (the measure of the longitudinal inclination of

420-421: A more defined and formalized profession with the emergence of architecture as a distinct profession from engineering during the industrial revolution in the late 19th century. Until then, the architect and the structural engineer were usually one and the same thing – the master builder. Only with the development of specialized knowledge of structural theories that emerged during the 19th and early 20th centuries, did

480-416: A partial collapse of the three-story schoolhouse that sent neighbors fleeing. The final collapse killed 94 people, mostly children. In other cases structural failures require careful study, and the results of these inquiries have resulted in improved practices and a greater understanding of the science of structural engineering. Some such studies are the result of forensic engineering investigations where

540-427: 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

600-479: A structure to move freely with the ground. Civil structural engineering includes all structural engineering related to the built environment. It includes: 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

660-427: A vessel's shape was judged by looking at a half-model of a vessel or a prototype. Ungainly shapes or abrupt transitions were frowned on as being flawed. This included rigging, deck arrangements, and even fixtures. Subjective descriptors such as ungainly , full , and fine were used as a substitute for the more precise terms used today. A vessel was, and still is described as having a ‘fair’ shape. The term ‘fair’

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720-461: Is IABSE(International Association for Bridge and Structural Engineering). 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. 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 that fulfills its functional requirements and

780-409: Is a complex non-linear relationship. 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. Beams are elements that carry pure bending only. Bending causes one part of the section of

840-494: Is being applied to predict the response of a floating body in a random sea. Due to the complexity associated with operating in a marine environment, naval architecture is a co-operative effort between groups of technically skilled individuals who are specialists in particular fields, often coordinated by a lead naval architect. This inherent complexity also means that the analytical tools available are much less evolved than those for designing aircraft, cars and even spacecraft. This

900-444: Is due primarily to the paucity of data on the environment the marine vehicle is required to work in and the complexity of the interaction of waves and wind on a marine structure. A naval architect is an engineer who is responsible for the design, classification, survey, construction, and/or repair of ships, boats, other marine vessels, and offshore structures, both commercial and military, including: Some of these vessels are amongst

960-509: Is equal to the weight of the body, in other words, the mass of the body is equal to the mass of the water displaced by the body. This adds an upward force to the body by the amount of surface area times the area displaced in order to create an equilibrium between the surface of the body and the surface of the water. The stability of a ship under most conditions is able to overcome any form or restriction or resistance encountered in rough seas; however, ships have undesirable roll characteristics when

1020-475: Is meant to denote not only a smooth transition from fore to aft but also a shape that was ‘right.’ Determining what is ‘right’ in a particular situation in the absence of definitive supporting analysis encompasses the art of naval architecture to this day. Modern low-cost digital computers and dedicated software , combined with extensive research to correlate full-scale, towing tank and computational data, have enabled naval architects to more accurately predict

1080-418: Is needed to ensure that the assumed collapse mechanism is realistic. 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 carry forces in compression in one direction only, which

1140-738: 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 structural design for a building must ensure that the building can 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 , cracking, and imposed loads. It must also ensure that

1200-426: Is sturdy enough to hold itself together the main force it has to overcome is longitudinal bending creating a strain against its hull, its structure must be designed so that the material is disposed as much forward and aft as possible. The principal longitudinal elements are the deck, shell plating, inner bottom all of which are in the form of grillages, and additional longitudinal stretching to these. The dimensions of

1260-416: 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

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1320-418: Is usually arranged so that the lines of force in the members are coincident at the joint thus allowing the truss members to act in pure tension or compression. Trusses are usually used in large-span structures, where it would be uneconomical to use solid beams. 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

1380-473: 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 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

1440-569: The Sunda Strait , between the Indonesian islands of Java and Sumatra would become too shallow for large ships. Other routes would therefore be required: Artificially excavated new routes might also be a possibility: Naval architecture The word "vessel" includes every description of watercraft , mainly ships and boats , but also including non-displacement craft, WIG craft and seaplanes , used or capable of being used as

1500-463: The structural design drawings or models, followed by erection and launching . Other joining techniques are used for other materials like fibre reinforced plastic and glass-reinforced plastic . The process of construction is thought-out cautiously while considering all factors like safety, strength of structure, hydrodynamics, and ship arrangement. Each factor considered presents a new option for materials to consider as well as ship orientation. When

1560-613: The Renaissance and have since developed into computer-based applications pioneered in the 1970s. The history of structural engineering contains many collapses and failures. Sometimes this is due to obvious negligence, as in the case of the Pétion-Ville school collapse , in which Rev. Fortin Augustin " constructed the building all by himself, saying he didn't need an engineer as he had good knowledge of construction" following

1620-477: The United States are accredited with Naval Architecture & Marine Engineering programs. The United States Naval Academy is home to one of the most knowledgeable professors of Naval Architecture; CAPT. Michael Bito, USN. Structural engineering Structural engineering is a sub-discipline of civil engineering in which structural engineers are trained to design the 'bones and joints' that create

1680-448: The ability to bring together the often-conflicting demands of the various design constraints to produce a product which is fit for the purpose. In addition to this leadership role, a naval architect also has a specialist function in ensuring that a safe, economic, environmentally sound and seaworthy design is produced. To undertake all these tasks, a naval architect must have an understanding of many branches of engineering and must be in

1740-517: The balance of oscillations in roll is two times that of oscillations in heave, thus causing the ship to capsize. Structures involves selection of material of construction, structural analysis of global and local strength of the vessel, vibration of the structural components and structural responses of the vessel during motions in seaway . Depending on type of ship, the structure and design will vary in what material to use as well as how much of it. Some ships are made from glass reinforced plastics but

1800-421: The body known as the hydrostatic pressures. The forces acting on the body must be of the same magnitude and same line of motion in order to maintain the body at equilibrium. This description of equilibrium is only present when a freely floating body is in still water, when other conditions are present the magnitude of which these forces shifts drastically creating the swaying motion of the body. The buoyancy force

1860-402: The center of gravity and the longitudinal meta-center. In other words, the basis in which the ship maintains its center of gravity is its distance set equally apart from both the aft and forward section of the ship. While a body floats on a liquid surface it still encounters the force of gravity pushing down on it. In order to stay afloat and avoid sinking there is an opposed force acting against

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1920-409: The column. The effective length is K ∗ l {\displaystyle K*l} where l {\displaystyle l} is the real length of the column and K is the factor dependent on the restraint conditions. 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

1980-441: 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 analyzed to give an upper bound on the collapse load. This technique is used in practice but because the method provides an upper-bound (i.e. an unsafe prediction of the collapse load) for poorly conceived collapse mechanisms, great care

2040-602: 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 structures are those engineered to withstand earthquakes . The main objectives of earthquake engineering are to understand

2100-645: The design of machinery, medical equipment, and vehicles where structural integrity affects functioning and safety. See glossary of structural engineering . Structural engineering theory is based upon applied physical laws and empirical knowledge of the structural performance of different materials and geometries. Structural engineering design uses a number of relatively simple structural concepts to build complex structural systems . Structural engineers are responsible for making creative and efficient use of funds, structural elements and materials to achieve these goals. Structural engineering dates back to 2700 B.C. when

2160-457: The design of structures, with the functionality to assist in the drawing, analyzing and designing of structures with maximum precision; examples include AutoCAD , StaadPro, ETABS , Prokon, Revit Structure, Inducta RCB, etc. Such software may also take into consideration environmental loads, such as earthquakes and winds. Structural engineers are responsible for engineering design and structural analysis. Entry-level structural engineers may design

2220-429: The external surfaces, bulkheads, and frames to support the shape and fasteners such as welds, rivets, screws, and bolts to hold the components together. 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

2280-485: The forefront of high technology areas. He or she must be able to effectively utilize the services provided by scientists, lawyers, accountants, and business people of many kinds. Naval architects typically work for shipyards , ship owners, design firms and consultancies, equipment manufacturers, Classification societies , regulatory bodies ( Admiralty law ), navies , and governments. A small majority of Naval Architects also work in education, of which only 5 universities in

2340-466: The form and shape of human-made structures . Structural engineers also must understand and calculate the stability , strength, rigidity and earthquake-susceptibility of built structures for buildings and nonbuilding structures . The structural designs are integrated with those of other designers such as architects and building services engineer and often supervise the construction of projects by contractors on site. They can also be involved in

2400-672: The individual structural elements of a structure, such as the beams and columns 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 types of structures, such as buildings, bridges, pipelines, industrial, tunnels, vehicles, ships, aircraft, and spacecraft. Structural engineers who specialize in buildings may specialize in particular construction materials such as concrete, steel, wood, masonry, alloys and composites. Structural engineering has existed since humans first started to construct their structures. It became

2460-461: The interaction of structures with the shaking ground, foresee the consequences of possible earthquakes, and design and construct the structures to perform during an earthquake. Earthquake-proof structures are not necessarily extremely strong like the El Castillo pyramid at Chichen Itza shown above. One important tool of earthquake engineering is base isolation , which allows the base of

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2520-412: 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

2580-484: The largest (such as supertankers ), most complex (such as aircraft carriers ), and highly valued movable structures produced by mankind. They are typically the most efficient method of transporting the world's raw materials and products. Modern engineering on this scale is essentially a team activity conducted by specialists in their respective fields and disciplines. Naval architects integrate these activities. This demanding leadership role requires managerial qualities and

2640-574: The largest ships capable of fitting through the Panama Canal , the Suez Canal and Saint Lawrence Seaway , respectively. Aframax tankers are those with a deadweight tonnage of 80,000 to 120,000. Some Chinamax and most Capesize and very large crude carriers cannot pass this strait. Ships such as Suezmax and Neopanamax can pass. Any post-Malaccamax ship would need to use even longer alternate routes because traditional seaways such as

2700-477: The longitudinal by about 3 or 4 meters, with the wide spacing this causes the traverse strength needed by displacing the amount of force the bulkheads provide. Arrangements involves concept design , layout and access, fire protection , allocation of spaces, ergonomics and capacity . Construction depends on the material used. When steel or aluminium is used this involves welding of the plates and profiles after rolling , marking, cutting and bending as per

2760-478: The micrometer range. The term 'nanostructure' is often used when referring to magnetic technology. 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

2820-508: The nanoscale, i.e., only the thickness of the surface of an object is between 0.1 and 100 nm. Nanotubes 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

2880-631: 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. 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

2940-411: The people responsible for maintaining a facility's medical equipment. Any structure is essentially made up of only a small number of different types of elements: Many of these elements can be classified according to form (straight, plane / curve) and dimensionality (one-dimensional / two-dimensional): Columns are elements that carry only axial force (compression) or both axial force and bending (which

3000-407: The performance of a marine vehicle. These tools are used for static stability (intact and damaged), dynamic stability, resistance, powering, hull development, structural analysis , green water modelling, and slamming analysis. Data are regularly shared in international conferences sponsored by RINA , Society of Naval Architects and Marine Engineers (SNAME) and others. Computational Fluid Dynamics

3060-451: The professional structural engineers 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

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3120-418: The pyramid, whilst primarily gained from its shape, relies also on the strength of the stone from which it is constructed, and its ability to support the weight of the stone above it. The limestone blocks were often taken from a quarry near the building site and have a compressive strength from 30 to 250 MPa (MPa = Pa × 10 ). Therefore, the structural strength of the pyramid stems from the material properties of

3180-478: The ship are in order to create enough spacing between the stiffeners in prevention of buckling. Warships have used a longitudinal system of stiffening that many modern commercial vessels have adopted. This system was widely used in early merchant ships such as the SS Great Eastern , but later shifted to transversely framed structure another concept in ship hull design that proved more practical. This system

3240-435: The step pyramid for Pharaoh Djoser was built by Imhotep , the first engineer in history known by name. Pyramids 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). The structural stability of

3300-463: The stones from which it was built rather than the pyramid's geometry. Throughout ancient and medieval history most architectural design and construction were carried out by artisans, such as stonemasons and carpenters, 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' and intuition . Knowledge

3360-519: The strength of the structure is considered the acts of ship collision are considered in the way that the ships structure is altered. Therefore, the properties of materials are considered carefully as applied material on the struck ship has elastic properties, the energy absorbed by the ship being struck is then deflected in the opposite direction, so both ships go through the process of rebounding to prevent further damage. Traditionally, naval architecture has been more craft than science. The suitability of

3420-463: The vast majority are steel with possibly some aluminium in the superstructure. The complete structure of the ship is designed with panels shaped in a rectangular form consisting of steel plating supported on four edges. Combined in a large surface area the Grillages create the hull of the ship , deck, and bulkheads while still providing mutual support of the frames. Though the structure of the ship

3480-403: The vessel) and stability (the ability of a vessel to restore itself to an upright position after being inclined by wind, sea, or loading conditions). While atop a liquid surface a floating body has 6 degrees of freedom in its movements, these are categorized in either translation or rotation. Longitudinal stability for longitudinal inclinations, the stability depends upon the distance between

3540-529: Was later implemented on modern vessels such as tankers because of its popularity and was then named the Isherwood System . The arrangement of the Isherwood system consists of stiffening decks both side and bottom by longitudinal members, they are separated enough so they have the same distance between them as the frames and beams. This system works by spacing out the transverse members that support

3600-565: Was retained by guilds and seldom supplanted by advances. Structures were repetitive, and increases in scale were incremental. No record exists of the first calculations of the strength of structural members or the behavior of structural material, but the profession of a structural engineer only really took shape with the Industrial Revolution and the re-invention of concrete (see History of Concrete ). The physical sciences underlying structural engineering began to be understood in

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