Tiles for houses and space schuttle orbiters.

Shuttle orbiters use a system of 30,000 tiles made of a silica compound that does not ablate, but does rapidly radiate heat away from the orbiter. These tiles are made of ceramic materials and must be able to withstand a temperature of nearly 1650 C. The orbiter's outer structural skin is constructed primarily of aluminum and graphite epoxy. The high-temperature Reusable Surface Insulation (HRSI) tiles are made of a low-density, high-purity silica 99.8 % amorphous fiber insulation that is made rigid by ceramic bonding. Because 90% of the tile is void and the remaining 10% is material, the tile weighs approximately 144 kg/m3.

31 - What is concrete? Historical evidences of concrete development and application.

Concrete is a manmade building material that when hardened looks like stone. Combining cement with aggregate and sufficient water makes concrete. Water allows it to set and bind the materials together. Concrete is a compound material made from sand, gravel and cement. The cement is a mixture of various minerals which when mixed with water, hydrate and rapidly become hard. The oldest known surviving concrete is to be found in the former Yugoslavia and was thought to have been laid in 5,600 BC using red lime as the cement. The first major concrete users were the Egyptians in around 2,500 BC and the Romans from 300 BC. The Romans found that by mixing a pink sand-like material which they obtained from Pozzuoli with their normal lime-based concretes they obtained a far stronger material. The Romans made many developments in concrete technology including the use of lightweight aggregates as in the roof of the Pantheon, and embedded reinforcement in the form of bronze bars. Laid in the shape of arches, vaults and domes, and, it quickly hardened into a rigid mass, free from many of the internal thrusts and strains which trouble the builders of similar structures in stone or brick.

32 - What are the main chemical admixtures of concrete? For what they are required?

Chemical admixtures are materials in the form of powder that are added to the concrete to give it certain characteristics not obtainable with plain concrete mixes. In normal use, admixture dosages are less than 5% by mass of cement, and are added to the concrete at the time of batching/mixing. The most common types of admixtures are: accelerators (speed up the hydration of the concrete), acrylic retarders (slow the hydration of concrete), air entrainments (add and distribute tiny air bubbles in the concrete, which will reduce damage during freeze-thaw cycles thereby increasing the concrete's durability), plasticizers (increase the workability of plastic or "fresh" concrete, allowing it be placed more easily, with less consolidating effort), pigments (can be used to change the color of concrete), corrosion inhibitors (used to minimize the corrosion of steel and steel bars in concrete) and bonding agents (used to create a bond between old and new concrete).

33 - What is pozzolana? For what it is used?

Pozzolana is any siliceous or siliceous and aluminous material which possesses little or no cementitious value in itself but will, if finely divided and mixed with water, chemically react with calcium hydroxide to form compounds with cementitious properties.This product was the first 'pozzolanic' cement.

34 - What is Portland cement? How it made?

The Portland cement is the most widely used type of cement, and is used as a binder in the preparation of the concrete. Portland cement was first used in concrete in the early 1840s when inventor Joseph Aspdin invented Portland cement. He made concrete by burning grounded chalk and finely crushed clay in a limekiln till the carbon dioxide evaporated, resulting in strong cement.

35 - What is reinforced concrete? What materials are used for reinforcement? For what it is used

Reinforced concrete (RC) is a composite material in which concrete's relatively low tensile strength and ductility are counteracted by the inclusion of reinforcement having higher tensile strength. The reinforcements are usually steel reinforcing bars and is usually embedded passively in the concrete before the concrete sets. It was invented in 1849 for tolerating heavy loads. Known as the strongest building material, concrete has found major uses in dams, highways, buildings and many different kinds of building and construction.

36 - What three principles should satisfy a good building?

A good building should satisfy the three principles: durability (firmitas) - it should stand up robustly and remain in good condition; utility (utilitas) - it should be useful and function well for the people using it; beauty (venustas) - it should delight people and raise their spirits.

37 - What architectural monuments of ancient world do you know?

I know many architectural monuments ancient world: palace of Knossos in Crete; The Taj Mahal in India; The Parthenon in Athens; the temple of Hera in Paestum; The Pantheon in Rome; Villa Adriana in Tivoli; The Domus Aurea in Rome; The Colosseum in Rome; Hagia Sophia in Istanbul; The Ziggurat of Ur; the Temple of Jerusalem; the Palatine Chapel, the Zisa and Cuba in Palermo; the Pyramid of Cheops in Egypt.

38 - What is Vernacular architecture?

Vernacular architecture is a building designed by an amateur without any training in design. The function of the building would be the dominant factor. The aesthetic considerations, though present to some small degree, being quite minimal. Local materials would be used as a matter of course.

Examples of vernacular architecture in Italy are the trulli in Puglia and the Aeolian architecture.

39 - What the main peculiarities of Olmec, Maya, Inca, Nasca architecture?

The Olmec civilization is the name given to a sophisticated central American culture with its heyday between 1200 and 400 BC. The most recognized aspect of the Olmec civilization are the enormous helmeted heads. It is now generally accepted that these heads are portraits of rulers. The heads range in size from 3.4 m high to 1.47 m.

The first clearly “Maya” settlements were established in approximately 1800 BC. The most notable monuments are the stepped pyramids they built in their religious centers. The Maya centers went into decline during the 8th and 9th centuries.

The Inca people began as a tribe in the Cuzco area around the 12th century AD. The Inca civilization was the largest civilization in the Americas when the Spanish conquistadors arrived in the early 16th century. Known for their unique writing system, a magnificent road system, and the lovely residence called Machu Picchu. Inca architecture was by far the most important of the Inca arts. The Incas had no iron or steel, but they had developed an alloy of bronze. The Incas introduced to South America the tin / copper alloy which is today commonly associated with "Bronze Age" metallurgy.

The Nasca civilization was located in the Nasca region on the southern coast of Peru. The Nasca culture is characterized by its beautiful polychrome pottery painted with at least 15 distinct colors. The Nasca had no writing system, in contrast to the contemporary Maya, thus the iconography or symbols painted on their ceramics served as a means of communication. The Nasca are also known for their technically complex textiles. The Nasca people created an hydraulic system to sustain life in the exceedingly arid environment. This irrigation system was made up of underground channels, known as puquios, which tapped into the subsurface water beneath the ground. The channels were dug into the mountainside until they reached the aquifers under the surface. The famous remnants of Nasca civilization are the Nazca Lines – vast line drawings of animals and abstract figures that can be seen from Space.

40 - What the main peculiarities of Egipt architecture?

In many ancient civilizations, like the Egyptians', architecture and urbanism reflected the constant engagement with the divine and the supernatural. The Egyptian civilization has left us some of the most magnificent monuments of antiquity: the pyramids, perfect prism four-sided pyramid triangolari.Una is however a building of special nature. Intended for burial, it was made up of interior, of impenetrable access. The pyramids, therefore, presented themselves as the gigantic structures, most architectures that do not true. The pyramids were built in a period between 2,650 and 2,350 BC, later fell into disuse, and the pharaohs, for their tombs built temples with columns shaped papyrus. The Egyptians adopted, therefore, the system trilithic. These temples were characterized by huge rooms filled with tall columns at close range. The Egyptian architecture, in its character of great grandeur, fixed one of the rules followed by the more forward planning, that of symmetry. Stone was built only then all that was to last forever, and in fact are today the only remaining buildings: tombs and temples. The architecture is the ultimate expression of Egyptian art and is mainly linked to religious themes. The Egyptians were the indefatigable builders and great technical expertise to the point of lift huge boulders weighing tons to enormous heights. Despite the enormity of the buildings, these elements are never looming heaviness. The private architecture and civil is not much documented.

41 - What the main peculiarities of Greek and Roman civilizations architecture?

Ancient Greek and Roman civilization have made many lasting contributions to western civilization.

The architecture and urbanism of the Classical civilizations such as the Greek and the Roman evolved from civic ideals rather than religious or empirical ones and new building types emerged.

The temple and theatre was the most common and best-known forms of Greek public architecture. Common materials of Greek architecture were:

wood, used for supports and roof beams; plaster, used for sinks and bathtubs; unbaked brick, used for walls, especially for private homes; limestone and marable, used for columns, walls, and upper portions of temples and public buildings; terracotta, used for roof tiles and ornaments; metals, especially bronze, used for decorative details.

The Architecture of Ancient Rome adopted the external Greek architecture around 12th century B.C. for their own purposes, creating a new architectural style. The Roman use of the arch and their improvements in the use of concrete and bricks facilitated the building of the many aqueducts throughout the empire. The dome permitted construction of vaulted ceilings and provided large covered public space such as the public baths and basilicas. Ancient Roman developments in housing and public hygiene are impressive, especially given their day and age. Clear examples are public and private baths and latrines, and under-floor heating, double glazing, and piped water. Some of the most impressive public buildings are the amphitheatres, over 220 being known and many of which are well preserved, such as the Colosseum in Rome.

42 - What the main peculiarities of Renaissance architecture?

The architecture of the Renaissance is that phase of European, and especially Italian, which developed in the early fifteenth century in Florence, primarily thanks to the work of some artists and intellectuals such as Filippo Brunelleschi and Leon Battista Alberti. The term Renaissance was used to highlight the rediscovery of Roman architecture. Main index of this discovery was the resumption of the classical orders, the use of geometric shapes for the definition of the plants, the search for orthogonal joints and symmetrical, and the use of harmonic proportion in the individual parts of the building. He had a decisive influence also the study of perspective by Filippo Brunelleschi.

Main buildings constructed in this period were: the palaces and villas (eg Rucellai Palace and the Venetian villas of Palladio, the Rotunda); churches, famous is the story of the basilica of St. Peter in Rome, completed the project of Michelangelo; and finally they built numerous libraries, among these, the most popular is the Laurentian Library by Michelangelo.

43 - What the main peculiarities of to-day architecture?

Architecture today usually requires a team of specialist professionals, with the architect being one of many. The field of architecture saw the rise of specializations by project type, technological expertise or project delivery methods. There has been an increased separation of the 'design' architect from the 'project' architect. To satisfy the contemporary ethos a building should be constructed in a manner which is environmentally friendly. In terms of the production of its materials, its impact upon the natural and built environment of its surrounding area and the demands that it makes upon non-sustainable power sources for heating, cooling, water and waste management and lighting. In the late 20th century a new concept was added to those included in the compass of both structure and function, the consideration of sustainability. There has been an acceleration in the number of buildings which seek to meet green building sustainable design principles. An example of green building is the Dynamic Tower which will be powered by wind turbines and solar panels.

44 - What is Civil engineering? How it is classified by engineering areas?

Civil engineering is a professional engineering that deals with the design, construction and maintenance of built environment, including works such as bridges, roads, canals, dams and buildings. It is classified by engineering areas:

Coastal engineering is concerned with managing coastal areas and defence against flooding and erosion.

Construction engineering involves planning and execution of the designs from transportation, site development, hydraulic, environmental, structural and geotechnical engineers.

Earthquake engineering covers ability of various structures to withstand hazardous earthquake exposures at the sites of their particular location.

Environmental engineering deals with the treatment of chemical, biological, or thermal waste, the purification of water and air, and the remediation of contaminated sites.

Geotechnical engineering is an area of civil engineering concerned with the rock and soil that civil engineering systems are supported.

Water resources engineering is intimately related to the design of pipelines, water distribution systems, drainage facilities (including bridges, dams, channels, culverts, storm sewers), and canals.

Material engineering deals with ceramics such as concrete, mix asphalt concrete, metals such as aluminum and steel, and polymers and carbon fibers.

Structural engineering. Structural engineering is concerned with the structural design of buildings, bridges, towers, flyovers, tunnels and other structures. Design considerations will include strength, stiffness, and stability of the structure when subjected to loads which may be static or dynamic.

Transportation engineering is concerned with moving people and goods efficiently, safely, and in a manner conducive to a vibrant community. This involves specifying, designing, constructing, and maintaining transportation infrastructure which includes streets, canals, highways, rail systems, airports, ports, and mass transit.

45 - What is surveying? Why it very important for civil engineering?

Surveying is the process by which a surveyor measures certain dimensions that occur on the surface of the Earth. Surveying equipment, such as levels and theodolites, are used for accurate measurement of angular deviation, horizontal, vertical and slope distances. This information is then used by civil engineers to design structures.

The surveying is important because it allows to build, in modern architecture, buildings that require precision levels of 0.1mm.

Types of bridges.

There are six main types of bridges:

beam bridges (horizontal beams supported at each end by piers. Weight on top of the beam pushes straight down on the piers at either end of the bridge. They are made up mostly of wood or metal);

cantilever bridges (built using cantilevers—horizontal beams that are supported on only one end. Most cantilever bridges use two cantilever arms extending from opposite sides of the obstacle to be crossed, meeting at the center);

arch bridges (are arch-shaped and have abutments at each end. The earliest known arch bridges were built by the Greeks. The weight of the bridge is thrust into the abutments at either side);

suspension bridges (suspended from cables. The earliest suspension bridges were made of ropes. In modern bridges, the cables hang from towers that are attached to caissons or cofferdams);

cable-stayed bridges (like suspension bridges, cable-stayed bridges are held up by cables. However, in a cable-stayed bridge, less cable is required and the towers holding the cables are proportionately shorter. The first known cable-stayed bridge was designed in 1784);

truss bridges (are composed of connected elements. They have a solid deck and a lattice of pin-jointed or gusset-joined girders for the sides. Early truss bridges were made of wood, and later of wood with iron tensile rods, but modern truss bridges are made completely of iron and steel or sometimes of reinforced concrete).

Date: 2016-01-03; view: 924