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This document discusses different types of shell structures used in construction. It begins by defining shell structures as thin curved membranes or slabs, usually of reinforced concrete, that function as both structure and covering. It then describes various forms of curvature for shells including surfaces of revolution, translation, and ruled surfaces. It discusses developable and non-developable shells and provides examples of different shell structures like barrel vaults, domes, folded plates, and more. It also covers topics like suitable materials, centering, and construction of reinforced concrete barrel vaults.
Study of Folded Plates for understanding their use, types, technology along with suitable case studies. This is a specific type of Methodology adopted for construction over long spans column free spaces. How structurally Folded plates surpases the need of column grids and conventional methods of construction with the proper design and technology is the motive of this study.
This document provides information on various types of shell structures and folded plate structures. It discusses thin shell structures and the differences between shell structures and plate structures. It then describes various types of shell structures including barrel vaults, domes, folded plates, and intersection shells. It provides details on the design and analysis of these structures, including their elements, behaviors, and reinforcement.
A tensile structure carries only tension and no compression or bending forces. It uses a fabric material stretched over a framework to provide stability. Tension roofs are loaded only in tension with no resistance to compression or bending. Tensile structures have environmental benefits like longer lifecycles, reusability, and recyclability with less construction debris. They provide flexible design aesthetics, translucency, durability, lightweight construction, and cost benefits from reduced energy usage. Common types include free-standing, mast-supported, and arch-supported structures.
This document discusses and compares cable-stayed and suspension bridge structures. It defines cables as flexible structural components that can only support tensile loading. There are two main types of cable structures: suspension and stayed cables. Suspension bridges hang the deck below suspension cables on vertical suspenders, while cable-stayed bridges support the deck with cables running directly from towers. Cable-stayed bridges have advantages like faster construction and higher stiffness compared to more flexible suspension bridges.
Folded plate and shell structures are thin-walled building structures that are lightweight yet rigid. Folded plate roofs use simpler calculations and formwork than shells. Modern folded plates are made of cast-in-place or precast concrete or steel. Shell structures come in various types including concrete shells, lattice shells, and membrane structures. Common shell structures include hyperbolic shells, parabolic shells, and cylindrical shells, with examples like the Calgary Saddledome. Paraboloids are a type of curved surface that can be elliptical, hyperbolic, or a combination to create rigid structural forms.
This document discusses different types of structural systems. It defines structure and explains that structures can be man-made or natural. Man-made structures are constructed by humans, while natural structures occur without human involvement. The document then discusses four main types of structural systems: section/bulk active systems using rigid elements to redirect forces through bending; vector active systems using tension and compression elements; form active systems relying on flexible elements and particular shapes; and surface active systems using planar elements under tension, compression or shear. Examples are provided for each type of structural system.
Folded plate structures are assemblies of flat plates rigidly connected along their edges that can carry loads without internal beams. They are simpler to manufacture than other shell structures using less material. Folded plates have intrinsic rigidity and high load capacity, making them economical for long spans without obstructions. Types include prismatic, pyramidal, and prismoidal plates in frames, roofs, or spatial configurations. Folded plates are used for gymnasium roofs, chapel walls, floor decking, and retaining sheet piles.
The document provides information about space frames. It discusses that a space frame is a truss-like, lightweight rigid structure constructed from interlocking struts in a geometric pattern. Space frames can span large areas with few interior supports because they are strong due to the inherent rigidity of triangles and how loads are distributed as tension and compression along struts. The document outlines different types of space frame configurations based on curvature and number of grid layers, and discusses their properties, design, construction, and historical development.
Tensile structures provide large column-free interior spaces through the use of tensioned fabric membranes maintained under tension by cable or truss networks. They offer several advantages over conventional structures like flexibility in design, natural daylighting, low costs, and minimal maintenance. However, the lightweight nature of fabric requires careful consideration of structural form finding, static and dynamic load analysis, and material patterning during the design process to develop stable, efficient tensile structures.
The document discusses cable structure systems used in architectural design. It defines a cable structure as a form-active structure system that uses tension to support loads through non-rigid, flexible materials shaped into a certain configuration. The key components of cable structure systems are described, including the cable materials (PTFE-coated fiberglass fabric, steel, rubber), construction method of attaching cables to anchor points, and issues of dynamic wind effects that require strategies like adding guy cables. Advantages are highlighted such as lightweight construction, large spans, design freedom, and cost efficiency, while disadvantages include potential issues with maintenance and vulnerability to damage.
Portal frames are low-rise structures comprising columns and horizontal or pitched rafters connected by moment-resisting connections. They provide clear unobstructed spans and are efficient for enclosing large volumes, making them useful for industrial, commercial, and agricultural buildings. Girder-slab systems combine a structural steel frame with prefabricated concrete girders and slabs for fast construction of mid-to-high rise buildings. Shell structures are thin curved concrete structures that function as both structure and enclosure through their strength and rigidity provided by their form. Common shell structures include folded plate, barrel vaults, and domes of revolution.
Taipei 101 is a 508-meter tall skyscraper in Taipei, Taiwan. It was the tallest building in the world from 2004 to 2010. The tower has 101 floors above ground and 5 floors underground. It was designed to withstand typhoons and earthquakes common in the area. The building uses a tube-in-tube structural system with a reinforced concrete core and steel perimeter columns. Outrigger trusses connect the core columns to the perimeter columns every eight floors to provide increased stability and resistance to strong winds.
Cable structures are made of small steel strands twisted together into larger cables. Cables are flexible structural components that can be used in suspension bridges and roofs. There are two main types of cable structures: suspension bridges, where cables support a stiff girder, and cable-stayed bridges, where cables support a continuous girder from towers.
Tensile structures carry only tension forces and no compression or bending. Common tensile structures include fabric membranes stretched over a framework and tension roofs with all parts in tension. Membranes take anticlastic or synclastic shapes to remain stable.
Common tensile membrane materials include PVC, PTFE, and FRP. PVC and PTFE membranes
This document discusses sun shading devices used to control solar radiation entering buildings. It describes different types of internal and external shading devices, including curtains, blinds, louvers and overhangs. It explains how shading devices improve thermal comfort and energy efficiency by reducing heat gains and cooling loads. The document also discusses how to select and design shading devices based on factors like orientation, climate and sun path. It describes how to calculate the horizontal and vertical shadow angles needed to determine a shading device's size and effectiveness.
The bundled tube structure meant that "buildings no longer need be boxlike in appearance: they could become sculpture." Hybrids. Hybrids include a varied category of structures where the basic concept of tube is used, and supplemented by other structural support(s).
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The document discusses various bulk active structural systems including columns, walls, beams, and slabs. It provides examples of different types of columns, walls, beams, and their configurations. Specific structures are described like the Torino Exhibition Hall with its thin corrugated vaulted roof made of precast ferrocement components. The Clamart Sports Center in France is also summarized, which has a complex curved roof structure made of over 1000 unique steel assemblies to follow the landscape.
The document discusses different types of roof trusses including king post truss, queen post truss, Howe truss, Pratt truss, fan truss, and north light roof truss. It describes the advantages of roof trusses such as being cost effective, allowing for quick installation, and providing stability. Tubular steel trusses are discussed as being used for large span constructions over 25-30 meters. The advantages of tubular steel trusses include reduced maintenance costs and corrosion resistance compared to other materials.
The document discusses space frames, which are lightweight, truss-like structures constructed from interlocking struts in a geometric pattern. Space frames can span large areas with few interior supports by transmitting loads through tension and compression along the length of each strut. They are made of steel or timber and can be used for applications like sports arenas, assembly halls, airports, and workshops. Space frames come in single, double, or triple layer configurations and use node connectors to link the elements. Their advantages include being light, stiff, economical to construct, and allowing freedom of longer spans. Their disadvantage is they can be difficult to engineer due to complex force distributions.
Pneumatic structures are membrane structures stabilized by compressed air pressure. They are round in shape to create the greatest volume with the least material. The pressure needs to be uniformly distributed for stability. Common types are air supported structures, which use air pressure above atmospheric to support the envelope, and air inflated structures, which have supporting frames inflated with high pressure air while the interior remains at atmospheric pressure. Pneumatic structures offer advantages like light weight, rapid erection, and ability to span large distances, but require continuous air pressurization and have a relatively short lifespan. Common materials for the envelope include fiberglass, polyester, ETFE, and nylon.
This presentation is an attempt of a comprehensive study about Gridshell Structures.To understand the structure and it's principles we are going to take a look at it's definition. advantages, form development,materials, construction process and joint connections
In order to gain a better understanding of the structure, existing Gridshells have been analysed and studied in depth. Structures Analysed are The Savill Building, Mannheim Multihalle and Centre Pompidou Metz.
The document discusses trussed tube structures, which use diagonal bracing on the exterior of the building. This bracing transfers both gravity and lateral loads, allowing the structure to resist wind and seismic forces more effectively. It eliminates the need for interior columns, increasing interior space flexibility. Examples given are the John Hancock Center, with distinctive x-bracing that absorbs forces in all dimensions, and the Onterie Center, with perimeter diagonal shear walls that allow for fewer, more widely spaced columns and larger windows than framed tube structures.
structural glazing and curtain wall
MATERIAL USED
parts of structural glazing and curtain wall
history of glazing
glass description
case study according material
Tube structures and its type with comparison .Udayram Patil
Hollow tube section always provide greater strength. So the same concept is applied to the building. Tubed system is designed to act like a three dimensional hollow tube structure which result in increased load resistance .
The Turning Torso is a 190-meter residential skyscraper located in Malmo, Sweden that was designed by architect Santiago Calatrava. Some key details:
- It has a twisting form composed of nine concrete cubes that twist 90 degrees from the base to the top.
- The central concrete core provides structural support, containing elevators and staircases. An exterior steel exoskeleton transfers wind loads and allows the concrete floors to cantilever.
- Construction began in 2001 and was completed in 2005, using a unique climbing form system to pour the concrete floors which rotated 1.6 degrees with each level.
- The skyscraper contains residential units and office space and utilizes sustainable design principles
Folded plate structures are assemblies of flat plates rigidly connected along edges to form a structure without additional beams. They were first used in 1923 for an aircraft hangar. The principle is inspired by folding in nature like leaves and wings. Structural behavior depends on folding pattern and connections. Types include folded plate surfaces, frames, and spatial structures made of materials like concrete, metal, wood, and glass. Applications include roofs, walls, floors, and steel sheet piles. Advantages are light construction and longer spans while disadvantages include complex formwork and labor. Examples are the Air Force Academy Chapel and Yokohama Passenger Terminal. The document recommends using folded plates for portable homeless shelters in Bangladesh.
Shell structures are lightweight constructions that use curved shell elements, like those seen in aircraft fuselages, boat hulls, and large building roofs. A thin shell is defined as a structure with thickness small compared to other dimensions, where deformations are not large relative to thickness. Concrete shells are a common type of thin shell structure that provides open, unobstructed interiors through curved concrete forms without internal supports. Concrete shells can be made in single or double curvature designs and require centering during construction to support their curved shapes until the concrete cures.
The document provides information about space frames. It discusses that a space frame is a truss-like, lightweight rigid structure constructed from interlocking struts in a geometric pattern. Space frames can span large areas with few interior supports because they are strong due to the inherent rigidity of triangles and how loads are distributed as tension and compression along struts. The document outlines different types of space frame configurations based on curvature and number of grid layers, and discusses their properties, design, construction, and historical development.
Tensile structures provide large column-free interior spaces through the use of tensioned fabric membranes maintained under tension by cable or truss networks. They offer several advantages over conventional structures like flexibility in design, natural daylighting, low costs, and minimal maintenance. However, the lightweight nature of fabric requires careful consideration of structural form finding, static and dynamic load analysis, and material patterning during the design process to develop stable, efficient tensile structures.
The document discusses cable structure systems used in architectural design. It defines a cable structure as a form-active structure system that uses tension to support loads through non-rigid, flexible materials shaped into a certain configuration. The key components of cable structure systems are described, including the cable materials (PTFE-coated fiberglass fabric, steel, rubber), construction method of attaching cables to anchor points, and issues of dynamic wind effects that require strategies like adding guy cables. Advantages are highlighted such as lightweight construction, large spans, design freedom, and cost efficiency, while disadvantages include potential issues with maintenance and vulnerability to damage.
Portal frames are low-rise structures comprising columns and horizontal or pitched rafters connected by moment-resisting connections. They provide clear unobstructed spans and are efficient for enclosing large volumes, making them useful for industrial, commercial, and agricultural buildings. Girder-slab systems combine a structural steel frame with prefabricated concrete girders and slabs for fast construction of mid-to-high rise buildings. Shell structures are thin curved concrete structures that function as both structure and enclosure through their strength and rigidity provided by their form. Common shell structures include folded plate, barrel vaults, and domes of revolution.
Taipei 101 is a 508-meter tall skyscraper in Taipei, Taiwan. It was the tallest building in the world from 2004 to 2010. The tower has 101 floors above ground and 5 floors underground. It was designed to withstand typhoons and earthquakes common in the area. The building uses a tube-in-tube structural system with a reinforced concrete core and steel perimeter columns. Outrigger trusses connect the core columns to the perimeter columns every eight floors to provide increased stability and resistance to strong winds.
Cable structures are made of small steel strands twisted together into larger cables. Cables are flexible structural components that can be used in suspension bridges and roofs. There are two main types of cable structures: suspension bridges, where cables support a stiff girder, and cable-stayed bridges, where cables support a continuous girder from towers.
Tensile structures carry only tension forces and no compression or bending. Common tensile structures include fabric membranes stretched over a framework and tension roofs with all parts in tension. Membranes take anticlastic or synclastic shapes to remain stable.
Common tensile membrane materials include PVC, PTFE, and FRP. PVC and PTFE membranes
This document discusses sun shading devices used to control solar radiation entering buildings. It describes different types of internal and external shading devices, including curtains, blinds, louvers and overhangs. It explains how shading devices improve thermal comfort and energy efficiency by reducing heat gains and cooling loads. The document also discusses how to select and design shading devices based on factors like orientation, climate and sun path. It describes how to calculate the horizontal and vertical shadow angles needed to determine a shading device's size and effectiveness.
Folded plate structures are assemblies of flat plates rigidly connected along edges to form a structure without additional beams. They were first used in 1923 for an aircraft hangar. The principle is inspired by folding in nature like leaves and wings. Structural behavior depends on folding pattern and connections. Types include folded plate surfaces, frames, and spatial structures made of materials like concrete, metal, wood, and glass. Applications include roofs, walls, floors, and steel sheet piles. Advantages are light construction and longer spans while disadvantages include complex formwork and labor. Examples are the Air Force Academy Chapel and Yokohama Passenger Terminal. The document recommends using folded plates for portable homeless shelters in Bangladesh.
Shell structures are lightweight constructions that use curved shell elements, like those seen in aircraft fuselages, boat hulls, and large building roofs. A thin shell is defined as a structure with thickness small compared to other dimensions, where deformations are not large relative to thickness. Concrete shells are a common type of thin shell structure that provides open, unobstructed interiors through curved concrete forms without internal supports. Concrete shells can be made in single or double curvature designs and require centering during construction to support their curved shapes until the concrete cures.
Shells can be classified in several ways, including by the material used and thickness. Thin concrete shells are lightweight structures made of reinforced concrete without internal supports. Common thin concrete shell types include barrel shells, folded plates, hyperbolic paraboloids, domes, and translation shells. Barrel shells carry loads longitudinally and transversally, while domes provide a strong, stiff structure with double curvature. Thin concrete shells offer wide open interior spaces but require sealing and ventilation to prevent moisture issues.
Shells are curved structures that can transmit loads in multiple directions and are constructed using thin materials like concrete or reinforced concrete. They distribute loads across their surfaces through compressive, tensile and shear stresses. Large spherical domes are often constructed using inflated membranes as forms which provide support during construction. Domes over 300 feet require a grid structure to provide sufficient stiffness while minimizing weight. Shells and folded plates are constructed as uniform thin surfaces rather than stacked discrete pieces like frames. Domes, vaults, and barrel shells are examples of shell structures used in building construction.
The topic is about the basic concepts of shell structure. Shell structures are light weight construction using shell elements. These elements are typically curve and are assembled to make large structured.
Space frames are truss-like, lightweight rigid structures constructed from interlocking struts arranged in a geometric pattern. They were independently developed in the early 1900s and 1950s to span large areas with few interior supports. Space frames transfer loads through a three-dimensional arrangement of linear elements subjected only to axial tension or compression. Common materials used include steel and timber. Connections are made through various joint types, and space frames can be single, double or triple layered grids. They provide advantages like light weight, stiffness and versatility compared to other structures.
Space frames are three-dimensional structures composed of interconnected linear elements that transfer loads through a grid-like network. They are designed without intermediate columns, creating large open interior spaces. Space frames come in various types including two-way and three-way grids, and can be single, double, or triple-layered. They consist of tubular members and specialized connectors, such as tuball nodes, nodus connectors, and triodetic connectors. Space frames are light, economical, stiff structures that allow freedom in building design and easy integration of services. Examples include the San Siro Stadium in Milan and Stansted Airport in London.
Dokumen tersebut membahas tentang struktur cangkang. Struktur cangkang adalah bentuk struktural tiga dimensi yang kaku dan tipis dengan permukaan lengkung. Dokumen tersebut menjelaskan pengertian, sifat, persyaratan struktur, klasifikasi berdasarkan bentuk geometri dan penyaluran beban pada struktur cangkang. Beberapa contoh struktur cangkang dijelaskan seperti Sydney Opera House, Teater Imax Keong Emas
Shell structures are thin curved membranes or slabs that function as both structure and covering. They derive their strength from their thin, naturally curved form. Common types include barrel vaults with single curvature and domes with double curvature. Reinforced concrete is well-suited for constructing shells due to its ability to take any shape in formwork. Shells provide efficient, aesthetically pleasing roofing but require accurate formwork and specialized construction techniques.
Shell structure, In building construction, a thin, curved plate structure shaped to transmit applied forces by compressive, tensile, and shear stresses that act in the plane of the surface.
Skeleton or braced frame works are also called latticed structures or space frames. They are categorized based on their Gaussian curvature as having positive, negative, or zero curvature. Braced barrel vaults are a type of skeletal structure with single curvature. Shell structures are thin curved structures that function as both structure and enclosure. They can have single or double curvature and forms include domes, hyperboloids, conoids, and hyperbolic paraboloids. Centering is required to construct shell structures which adds to the cost but shell structures are aesthetically pleasing and efficient due to their light weight. An example is the Sydney Opera House which used precast concrete shell segments and tensioned steel cables to span over 350km and
Module - III.pptx shell structures and folded platesPrajaktaRahate2
Shell structures have been used for thousands of years, with early evidence of vaulted structures in Mesopotamia from 3000 BC. Shell structures are thin, curved plate structures that transmit applied forces through compressive, tensile, and shear stresses in the plane of the surface. They can be classified based on their curvature (single or double), shape (surface of revolution, translation, ruled), surface type (developable or non-developable), and material used (reinforced concrete, steel, etc.). Folded plate structures are assemblies of flat plates inclined in different directions and joined along edges, allowing slab and beam action to carry loads without additional internal supports.
This document discusses the geometric classification of folds in geology. It defines what folds are and describes their key features like hinge lines, axial planes, limbs, and amplitudes. It then categorizes folds based on various criteria such as the sense of curvature (anticline, syncline), direction of younging (anticlinal, synclinal), symmetry (symmetrical, asymmetrical), nature of the hinge line (cylindrical, non-cylindrical), plunge, interlimb angle, thickness, orientation, and shape of the hinge. It provides examples of different fold types and discusses parasitic folds. The document serves as a comprehensive overview of how folds are classified geometrically in structural geology.
1. The document discusses different types of folds classified based on their geometry, mode of occurrence, and causes of folding.
2. Key fold types include chevron, conjugate, cuspate, and cylindrical folds. Folds commonly occur in groups called anticlinoria, domes, and basins.
3. Folds form due to tectonic forces like tangential compression or due to intrusions, with flexural, flowage, and shear folding occurring under compression. Differential compression during sedimentation can also cause folding.
A Review on Thin-shell Structures: Advances and TrendsA Makwana
This paper provides a review of research advances and trends in the area of thin shell structures. The art of building thin-shell structures has been with us since ancient times. In practical civil engineering, the necessity of covering large column free open areas with shell surfaces is often an issue. Over the course of time, this shell form became very popular to engineers due to a number of advantages it offers, and started drawing the attention of a number of researchers. A thin shell is a term not in itself as readily understandable by the layman as the terms dome or vault would be. It is in a sense a word coined on the basis of its structural connotations, as exhibited in the artifacts it creates. There are many interesting aspects of the use of shells in engineering, but one alone stands out as being of paramount importance: it is the structural aspect. At the beginning of this century, under the influence of the art movement and the dominance of industrialized building materials, any remnants of curvilinear architecture were mercilessly banished. Within that period avant-garde art emphatically proclaimed a total repudiation of the traditions and classical revivals that in architecture were symbolized mostly by arches and vaults. Ready-to-use rectilinear steel beams and columns and easy-to build rectilinear concrete forms struck a lethal blow to the curvilinear approach in architecture. Rectilinearity became synonymous with rationality, while curvilinearity came to symbolize decadence. Remember, for instance, the negative stigma given to the baroque for its assumed pomposity in glorifying curves. In practical terms such an attitude in design is clearly manifested in the present cityscapes that are totally free of arches, domes, shells, and any other form that is not rectilinear. With today‟s almost unlimited computer technology and the knowledge that can be gained from understanding the domes and vaults built both in the past and present, it is hoped that this research work on the review aspects of curvilinear forms will contribute to further exploration and encourage the application of thin shells by the engineers and architects to whom it is addressed. Masonry domes, concrete shells, and large steel contemporary domes are presented in historical terms as case studies and in conceptual terms from the architectural and structural point of view.
Three business basics to always remember! People don't care about your brand. They care about what you can do for them. Back to basics... Give people what they want, do it consistently and do it better than your competition.
How to Craft Your Company's Storytelling Voice by Ann Handley of MarketingProfsMarketingProfs
You know your company's story, but what's the right voice to use in telling it? Find out how to craft your company's storytelling voice. Ann Handley, chief content officer of MarketingProfs and author of "Content Rules" shares tips and ideas for crafting your brand's storytelling voice.
This document outlines Netflix's culture of freedom and responsibility. Some key points:
- Netflix focuses on attracting and retaining "stunning colleagues" through a high-performance culture rather than perks. Managers use a "Keeper Test" to determine which employees they would fight to keep.
- The culture emphasizes values over rules. Netflix aims to minimize complexity as it grows by increasing talent density rather than imposing processes. This allows the company to maintain flexibility.
- Employees are given significant responsibility and freedom in their roles, such as having no vacation tracking or expense policies beyond acting in the company's best interests. The goal is to avoid chaos through self-discipline rather than controls.
- Providing
How To Embed SlideShare Shows Into WordPress.comKathy Gill
This document provides instructions for embedding a SlideShare presentation into a WordPress.com blog post or page. It outlines finding the desired SlideShare presentation, clicking embed or share, customizing options and copying the shortcode, pasting the shortcode into the WordPress post or page, and credits the author.
This document outlines Seth Familian's presentation on working with big data. It discusses key concepts like what constitutes big data, popular tools for working with big data like Splunk and Segment, and techniques for building dashboards and inferring customer segments from large datasets. Specific examples are provided of automated data flows that extract, load, transform and analyze big data from various sources to generate insights and populate customized dashboards.
We'd like to take a break on presentation techniques and share with our viewers a slideshow featuring leadership lessons from former South African President Nelson Mandela.
Transcript Below:
1.) “A good leader can engage in a debate frankly and thoroughly, knowing that at the end he and the other side must be closer, and thus emerge stronger. You don't have that idea when you are arrogant, superficial, and uninformed.”
“I learned that courage was not the absence of fear, but the triumph over it. The brave man is not he who does not feel afraid, but he who conquers that fear.”
2.) “It is better to lead from behind and to put others in front, especially when you celebrate victory when nice things occur. You take the front line when there is danger. Then people will appreciate your leadership.”
“Resentment is like drinking poison and then hoping it will kill your enemies.”
3.) “Long speeches, the shaking of fists, the banging of tables and strongly worded resolutions out of touch with the objective conditions do not bring about mass action and can do a great deal of harm to the organization and the struggle we serve.”
“Do not judge me by my successes, judge me by how many times I fell down and got back up again.”
4.) “Real leaders must be ready to sacrifice all for the freedom of their people.”
"Action without vision is only passing time, vision without action is merely day dreaming, but vision with action can change the world."
5.) “What counts in life is not the mere fact that we have lived. It is what difference we have made to the lives of others that will determine the significance of the life we lead.”
“Courageous people do not fear forgiving, for the sake of peace.”
We hope you enjoyed our latest SlideShare presentation!
24 Books You've Never Heard Of - But Will Change Your LifeRyan Holiday
Ryan Holiday provides a list of 24 books that are often overlooked but can profoundly change one's life. He argues that reading only popular books means not learning anything new, and encourages carving one's own path by exploring unexpected books. For the past 5 years, Holiday has recommended hundreds of amazing books through a monthly email newsletter. The document then summarizes each of the 24 books highlighted in the list.
Institute of Business Management- National Service Schemesumantabasak09
During Mahatma Gandhi’s Birth Centenary year, the National Service Scheme (NSS) started its journey in 1969. The scheme was first launched in 37 universities comprising of 40,000 students. Today, NSS has become the largest Government organization of students in the country, with members spanning from +2 levels to college and also at the university level. The number of volunteers has now increased to more than thirty lakhs, which makes NSS one of the largest student forces in the world.
How To Add Search Panel In Odoo 17 - Odoo SlidesCeline George
The slide will show how to add Search Panel in Odoo 17. The Search Panel provides a simplified filtering experience by allowing users to select predefined categories and filters, eliminating the need to manually enter search criteria.
Guru Gobind Singh Indraprastha University.pdfvignesh1012
Guru Gobind Singh Indraprastha University (GGSIPU), established in 1998, is a premier state university located in Delhi. Named after the revered Sikh Guru Gobind Singh, the university is known for its commitment to academic excellence and professional education. It serves as a hub for various disciplines, offering undergraduate, postgraduate, and doctoral programs in fields such as engineering, management, law, and health sciences. The university's vision is to achieve excellence in professional education and research while fostering values of integrity and service to society. Its mission includes providing quality education, promoting innovation, and creating a conducive environment for intellectual and personal growth. The institution aims to shape skilled professionals ready to meet the challenges of a dynamic world. GGSIPU boasts modern infrastructure. https://www.iesonline.co.in/guru-gobind-singh-indraprastha-university-new-delhi/
This brochure is being mailed to every library, archive, historical society, and genealogical society in all 120 Kentucky counties. You can download your copy of it here and feel free to share it with those who may benefit from it.
2. INTRODUCTION
LATTICE AND PORTAL FRAME BUILDINGS CONSIST OF A STRUCTURAL FRAME WHICH SUPPORTS SLAB, ROOF AND WALL
COVERING. THIS FRAME SERVES PURELY AS THE STRUCTURAL SUPPORT AND PROVIDES PROTECTION AGAINST WEATHER.
THE ROOF AND WALL COVERING ADD NOTHING TO THE STRENGTH THE RIGIDITY OF STRUCTURAL FRAME.
A SHELL STRUCTURE IS A THIN CURVED MEMBRANE OR SLAB USUALLY OF REINFORCED CONCRETE THAT FUNCTIONS
BOTH AS STRUCTURE AND COVERING.
THE TERM “SHELL” IS USED TO DESCRIBE THE STRUCTURES WHICH POSSESS STRENGHT AND RIGIDITY DUE TO ITS THIN,
NATURAL AND CURVED FORM SUCH AS SHELL OF EGG, A NUT, HUMAN SKULL, AND SHELL OF TORTISE.
SHELLS OCCURING IN NATURE
3. SINGLE OR DOUBLE CURVATURE SHELLS
SINGLE CURVATURE SHELL: ARE CURVED ON ONE LINEAR AXIS AND ARE A PART OF A CYLINDER OR CONE IN THE FORM OF
BARREL VAULTS AND CONOID SHELLS.
DOUBLE CURVATURE SHELL: ARE EITHER PART OF A SPHERE, OR A HYPERBOLOID OF REVOLUTION.
THE TERMS SINGLE CURVATURE AND DOUBLE CURVATURE DO NOT PROVIDE A PRECISE GEMOETRIC DISTINCTION
BETWEEN THE FORM OF SHELL BECAUSE A BARREL VAULT IS SINGLE CURVATURE BUT SO IS A DOME.
THE TERMS SINGLE AND DOULBE CURVATURE ARE USED TO DISTINGUISH THE COMPARITIVE RIGIDITY OF THE TWO
FORMS AND COMPLEXITY OF CENTRING NECESSARY TO CONSTRUCT THE SHELL FORM.
CONOID
DOME
BARREL VAULT
HYPERBOLOID
PARABOLOID
4. FORMS OF CURVATURE:
SURFACES OF REVOLUTION:
SURFACES OF REVOLUTION ARE GENERATED BY THE
REVOLUTION OF A PLANE CURVE, CALLED THE MERIDIONAL
CURVE,
ABOUT AN AXIS, CALLED THE AXIS OF REVOLUTION.
IN THE SPECIAL CASE OF CYLINDRICAL AND CONICAL
SURFACES, THE MERIDIONAL CURVE CONSISTS OF A LINE
SEGMENT.
E.G. : CYLINDERS, CONES,
SPHERICAL OR ELLIPTICAL DOMES,
HYPERBOLOIDS OF REVOLUTION, TOROIDS.
5. FORMS OF CURVATURE:
SURFACES OF TRANSLATION :
SURFACES OF TRANSLATION ARE GENERATED BY SLIDING A PLANE CURVE ALONG ANOTHER PLANE CURVE, WHILE
KEEPING THE ORIENTATION OF THE SLIDING CURVE CONSTANT.
THE LATTER CURVE, ON WHICH THE ORIGINAL CURVE SLIDES, IS CALLED THE GENERATOR OF THE SURFACE.
IN THE SPECIAL CASE IN WHICH THE GENERATOR IS A STRAIGHT LINE, THE RESULTING SURFACE IS CALLED A
CYLINDRICAL SURFACE.
SURFACES OF TRANSLATION WITH RECTANGULAR PLAN:
(A) ELLIPTIC PARABOLOID (B) CYLINDRICAL PARABOLOID (C) HYPERBOLIC PARABOLOID
6. FORMS OF CURVATURE:
SURFACES OF TRANSLATION :
IF TWO PARABOLAS ARE SIMILAR, THE SURFACE BECOMES A SURFACE OF REVOLUTION, CALLED PARABOLOID OF
REVOLUTION.
7. FORMS OF CURVATURE:
RULED SURFACES :
RULED SURFACES ARE GENERATED BY SLIDING EACH END OF A STRAIGHT LINE ON THEIR OWN GENERATING CURVE.
THESE LINES ARE NOT NECESSARILY AT RIGHT ANGLE TO THE PLANES CONTAINING THE END CURVES.
COOLING TOWER, GENERATED BY STRAIGHT
CONOID, GENERATED BY STRAIGHT LINE TRAVELING ALONG ANOTHER
LINES GOULD 1988
STRAIGHT LINE AT ONE END AND CURVED LINE AT OTHER END. JOEDICKE
1963
8. SHELLS
SINGLY CURVED
DOUBLY CURVED
(DEVELOPABLE SHELLS)
(NON DEVELOPABLE SHELLS)
SURFACES OF
REVOLUTION
CIRCULAR CYLINDER
(BARREL)
CONES
SURFACES OF
TRANSLATION/
RULED SURFACE
SYNCLASTIC
CIRCULAR OR
NON CIRCULAR CYLINDER
ANTYNCLASTIC
SURFACES OF
REVOLUTION
CONES
SURFACES OF
REVOLUTION
CIRCULAR DOMES
ELLIPSOID OF
REVOLUTION
PARABOLOIDS OF
REVOLUTION
SURFACES OF
TRANSLATION/
RULED SURFACE
ELLIPTIC
PARABOLOIDS
SURFACES OF
TRANSLATION/
RULED SURFACE
HYPERBOLOIDS OF
REVOLUTION OF
ONE SHEET
HYPERBOLIC
PARABOLOIDS
CONOIDS
PARABOLOIDS OF
REVOLUTION
HYPERBOLOIDS OF
REVOLUTION OF
ONE SHEET
9. FORMS OF CURVATURE:
DEVELOPABLE AND NONDEVELOPABLE SURFACES :
SURFACES WITH DOUBLE CURVATURE CANNOT BE DEVELOPED, WHILE THOSE WITH SINGLE CURVATURE CAN BE
DEVELOPED.
DEVELOPED
NONDEVELOPED
IN OTHER WORDS, SURFACES WITH POSITIVE AND NEGATIVE GAUSSIAN CURVATURE (I.E. SYNCLASTIC AND ANTICLASTIC
SURFACES) CANNOT BE DEVELOPED, WHILE THOSE WITH ZERO GAUSSIAN CURVATURE CAN BE DEVELOPED.
TYPES OF GAUSSIAN CURVATURE.
(A) POSITIVE GAUSSIAN
(B) ZERO GAUSSIAN
(C) NEGATIVE GAUSSIAN
10. FORMS OF CURVATURE:
DEVELOPABLE SURFACES (SINGLY CURVED) :
DEVELOPABLE SURFACE IS A SURFACE THAT CAN BE UNROLLED ONTO A FLAT PLANE WITHOUT TEARING OR STRETCHING
IT.
IT IS FORMED BY BENDING A FLAT PLANE, THE MOST TYPICAL SHAPE OF A DEVELOPABLE SHELL IS A BARREL, AND A
BARREL SHELL IS CURVED ONLY IN ONE DIRECTION.
BARREL :
ARCH ACTION & BEAM ACTION TOGETHER MAKE A BARREL.
THERE ARE MAINLY TWO TYPES OF BARREL :
- LONG BARRELS , ARCH ACTION IS PROMINENT
- SHORT BARRELS, BEAM ACTION IS PROMINENT
STRUCTURAL BEHAVIOR OF SHORT BARREL SHELLS:
THESE SHELLS ARE TYPICALLY SUPPORTED AT THE CORNERS
AND CAN BEHAVE IN ONE OR A COMBINATION OF THE
FOLLOWING WAYS:
STRUCTURAL BEHAVIOR OF LONG BARREL SHELLS:
THESE ARE TYPICALLY SUPPORTED AT THE CORNERS AND
BEHAVE STRUCTURALLY AS A LARGE BEAM.
11. FORMS OF CURVATURE:
NON-DEVELOPABLE SURFACES (DOUBLY CURVED) :
E.G., SPHERE OR HYPERBOLIC PARABOLOID.
THEY ARE MAINLY CLASSIFIED AS : 1) SYNCLASTIC 2) ANTICLASTIC
SYNCLASTIC SHELLS:
THESE SHELLS ARE DOUBLY CURVED
AND HAVE A SIMILAR CURVATURE IN EACH DIRECTION. E.G. DOMES
A DOME IS A GOOD EXAMPLE OF A SYNCLASTIC SHELL, IT IS DOUBLY CURVED AND CAN BE FORMED BY ROTATING A
CURVED LINE AROUND AN AXIS.
A DOME CAN BE SPLIT UP INTO TWO DIFFERENT DIRECTIONS; VERTICAL SECTIONS SEPARATED BY LONGITUDINAL ARCH
LINES (ALSO CALLED MERIDIANS), AND HORIZONTAL SECTIONS SEPARATED BY HOOPS OR PARALLELS.
STRUCTURAL BEHAVIOR :
SIMILAR TO ARCHES UNDER A UNIFORM LOADING THE DOME IS UNDER COMPRESSION EVERYWHERE, AND THE STRESSES
ACT ALONG THE ARCH AND HOOP LINES.
12. FORMS OF CURVATURE:
NON-DEVELOPABLE SURFACES (DOUBLY CURVED) :
ANTICLASTIC SHELLS : ARE DOUBLY CURVED BUT EACH OF THE TWO CURVES HAVE
THE OPPOSITE DIRECTION TO THE OTHER. E.G. SADDLE POINTS.
ANTICLASTIC
CONOIDS, HYPERBOLIC PARABOLOID AND HYPERBOLOIDS ARE ALL CONSIDERED TO
THE ANTICLASTIC SHELL BECAUSE THEY ARE SADDLED SHAPE WITH DIFFERENT
CURVATURE IN EACH DIRECTION AND STRAIGHT LINES CAN BE DRAWN OF THE
SURFACE.
CONOID
CONOIDS: FORMED BY MOVING A ONE END OF A STRAIGHT LINE ALONG A CURVED
PATH AND THE OTHER ALONG A STRAIGHT PATH.
HYPERBOLOIDS: FORMED BY ROTATING A STRAIGHT LINE AROUND A VERTICAL AXIS.
HYPERBOLOID
PARABOLOID
13. FORMS OF CURVATURE:
NON-DEVELOPABLE SURFACES (DOUBLY CURVED) :
HYPERBOLIC PARABOLOID:
FORMED BY SWEEPING A CONVEX PARABOLA ALONG A CONCAVE
PARABOLA OR BY SWEEPING A STRAIGHT LINE OVER A STRAIGHT PATH AT
ONE END AND ANOTHER STRAIGHT PATH NOT PARALLEL TO THE FIRST.
STRUCTURAL BEHAVIORS:
DEPENDING ON THE SHAPE OF THE SHELL RELATIVE TO THE CURVATURE,
THERE WILL BE DIFFERENT STRESSES.
SHELL ROOFS, HAVE COMPRESSION STRESSES FOLLOWING THE CONVEX
CURVATURE AND THE TENSION STRESSES FOLLOW THE CONCAVE
CURVATURE.
14. FORMS OF CURVATURE:
TENSION TIE :
FIG. (A) REPRESENTS A DOUBLY CURVED SHELL WITH NO AXIS OF SYMMETRY,
SHOWS A SPHERICAL DOME SUPPORTED ON A WALL.
WHENEVER THE SHELLS ARE SUPPORTED VERTICALLY AT THEIR EDGES, A TENSION
TIE IS REQUIRED AROUND THE PERIMETER AT THE INTERSECTION OF THE DOME
AND THE WALL.
HOWEVER, IT IS IMPORTANT TO NOTE THAT THE TIE WILL BE FUNICULAR FOR ANY
SHAPE OF EITHER THE PLAN OR
ELEVATION.
FIG. (B) THE SHELL HAS POSITIVE CURVATURE AND
CONTINUOUS VERTICAL SUPPORT.
15. FORMS OF CURVATURE:
TENSION TIE :
THE SUPPORT MAY BE A CONTINUOUS WALL OR STIFF BEAMS
BETWEEN ADEQUATELY SPACED COLUMNS. IT IS INTERESTING THAT
THE STRAIGHT PARTS OF THE TIE IN FIG. (C) DO NOT REQUIRE TIES
ACROSS THE BUILDING.
THE THRUSTS ARE TAKEN BY SHEAR FORCES THROUGH THE WIDTH
OF THE SHELL, AND ONLY TENSION FORCES EXIST IN THE TIE.
CYLINDRICAL SHELL COMBINED WITH SPHERICAL SHELL
16. TYPES OF SHELL STRUCTURES:
FOLDED PLATE SHELLS:
THE DISTINGUISHING FEATURE OF THE FOLDED PLATE IS THE EASE IN FORMING PLANE
SURFACES. A FOLDED PLATE MAY BE FORMED FOR ABOUT THE SAME COST AS A
HORIZONTAL SLAB AND HAS MUCH LESS STEEL AND CONCRETE FOR THE SAME SPANS.
THE PRINCIPLE COMPONENTS IN A FOLDED PLATE STRUCTURE CONSIST OF :
1) THE INCLINED PLATES
2) EDGE PLATES WHICH MUST BE USED TO STIFFEN THE WIDE PLATES
3) STIFFENERS TO CARRY THE LOADS TO THE SUPPORTS AND TO HOLD THE PLATES IN LINE
CANOPIES
4) COLUMNS TO SUPPORT THE STRUCTURE IN THE AIR.
FOLDED PLATE TRUSS
Z SHELL
TAPERED FOLDED PLATES
THREE SEGMENT FOLDED PLATE
17. TYPES OF SHELL STRUCTURES:
CYLINDRICAL BARREL VAULTS:
BARREL VAULTS ARE PERHAPS THE MOST USEFUL OF THE SHELL STRUCTURES BECAUSE THEY CAN SPAN UPT O 150 FEET
WITH A MINIMUM OF MATERIAL. THEY ARE VERY EFFICIENT STRUCTURES BECAUSE THE USE THE ARCH FORM TO REDUCE
STRESSES AND THICKNESSES IN THE TRANSVERSE DIRECTION.
CORRUGATED CURVES
UNSTIFFENED EDGES
MULTIPLE BARRELS OUTSIDE STIFFENERS
THE LAZY S
18. TYPES OF SHELL STRUCTURES:
DOMES OF REVOLUTION:
A DOME IS A SPACE STRUCTURE COVERING A MORE OR LESS
SQUARE OR CIRCULAR AREA. THE BEST KNOWN EXAMPLE IS
THE DOME OF REVOLUTION, AND IT IS ONE OF THE EARLIEST
SPHERE SEGMENT
OF THE SHELL STRUCTURES. EXCELLENT EXAMPLES ARE STILL
IN EXISTENCE THAT WERE BUILT IN ROMAN TIMES. THEY ARE
FORMED BY A SURFACE GENERATED BY A CURVE OF ANY
FORM REVOLVING ABOUT A VERTICAL LINE. THIS SURFACE
HAS DOUBLE CURVATURE AND THE RESULTING STRUCTURE
IS MUCH STIFFER AND STRONGER THAN A SINGLE CURVED
SURFACE, SUCH AS A CYLINDRICAL SHELL.
HALF SPHERE
DOMES - SQUARE IN PLAN
19. MOST SUITABLE MATERIAL
THE MATERIAL MOST SUITED FOR CONSTRUCTION OF SHELL STRUCTURE IS CONCRETE BECAUSE IT IS A HIGHLY PLASTIC
MATERIAL WHEN FIRST MIXED WITH WATER THAT CAN TAKE UP ANY SHAPE ON CENTERING OR INSIDE FORMWORK.
SMALL SECTIONS OF REINFORCING BARS CAN READILY BE BENT TO FOLLOW THE CURVATURE OF SHELLS.
ONCE THE CEMENT HAS SET AND THE CONCERETE HAS HARDENED THE R.C.C MEMBRANE OR SLAB ACTS AS A STRONG,
RIGID SHELL WHICH SERVES AS BOTH STRUCTURE AND COVERING TO THE BUILDING.
20. CENTERING OF SHELLS
CENTERING IS THE TERM USED TO DESCRIBE THE NECESSARY
TEMPORARY SUPPORT ON WHICH THE CURVED R.C.C SHELL
STRUCTURE IS CAST.
THE CENTERING OF A BARREL VAULT, WHICH IS PART OF A
CYLINDER WITH SAME CURVATURE ALONG ITS LENGTH; IS
LESS COMPLEX. THE CENTERING OF CONOID, DOME AND
HYPERBOLOID OF REVOLUTION IS MORE COMPLEX DUE TO
ADDITIONAL LABOUR AND WASTEFUL CUTTING OF
MATERIALS TO FORM SUPPORT FOR SHAPES THAT ARE NOT
OF UNIFORM LINEAR CURVATURE.
THE ATTRACTION OF SHELL STRUCTURES LIES IN THE
ELEGANT SIMPLICITY OF CURVED SHELL FORMS THAT UTILISE
THE NATURAL ATRENGTH AND STIFFNESS OF SHELL FORMS
WITH GREAT ECONOMY IN THE USE OF MATERIALS.
THE DISADVANTAGE OF SHELL STRUCTURE IS THEIR COST.
THE SHELL STRUCTURE IS MORE EXPENSIVE DUE TO
CONSIDERABLE LABOUR REQUIRED TO CONSTRUCT THE
CENTERING ON WHICH THE SHELL IS CAST.
21. CONSTRUCTION OF R.C.C BARREL VAULT
THE BARREL VAULT IS THE MOST STRAIGHT FORWARD
SINGLE CURVATURE SHELL CONSTRUCTION. IT IS THE PART
OF A CYLINDER OR BARREL WITH SAME CURVATUREALONG
ITS LENGTH.
ANY NUMBER OF CONTINUOUS BARRELS OR CONTINUOUS
SPANS ARE POSSIBLE EXCEPT THAT EVENTUALLY
PROVISION IS MADE FOR THE EXPANSION OF THE JOINTS
IN A LARGE STRUCTURES.
THE BARREL VAULTS ARE USED AS PARKING, MARKET
PLACE, ASSEMBLY HALL ,ETC.
TYPES OF BARREL VAULTS
1. SHORT SPAN BARREL VAULTS
2. LONG SPAN BARREL VAULTS
22. CONSTRUCTION OF R.C.C BARREL VAULT
SHORT SPAN BARREL VAULT
SHORT SPAN BARREL VAULTS ARE THOSE IN WHICH SPAN IS
SHORTER THAN ITS WIDTH. IT IS USED FOR THE WIDTH OF
THE ARCH RIBS BETWEEN WHICH THE BARREL VAULT SPAN.
LONG SPAN BARREL VAULT
LONG SPAN BARREL VAULTS ARE THOSE IN WHICH SPAN IS
LARGER THAN ITS WIDTH.
STRENGTH OF THE STRUCTURE LIES AT THE RIGHT ANGLES
TO THE CURVATURE TO THAT SPAN IS LONGITUDINAL TO
THE CURVATURE.
USUAL SPAN OF THE LONGITUDINAL BARREL VAULT IS
FROM 12-30 M WITH ITS WIDTH BEING ABOUT 1/2 THE SPAN
AND RISE IS 1/5 OF THE WIDTH.
TO COVER LARGER AREAS MULTIBAY ,MULTI SPAN ROOFS
CAN BE USED WHERE THE ROOF IS EXTENDED ACROSS THE
WIDTH OF THE VAULT AS A MULTIBAY .
23. CONSTRUCTION OF R.C.C BARREL VAULT:
STIFFENING BEAMS AND ARCHES:
UNDER LOCAL LOADS THE THIN SHELL OF THE BARREL
VAULT WILL TEND TO DISTORT AND LOSE SHAPE AND EVEN
COLLAPSE IF THE RESULTANT STRESSES WERE MORE. TO
STRENGTHEN THE SHELL AGAINST THIS POSSIBILITY,
STIFFENING BEAMS OR ARCHES ARE CAST INTEGRALLY
WITH THE SHELL.
THE COMMON PRACTICE IS TO PROVIDE A STIFFENING
MEMBER BETWEEN THE COLUMN SUPPORTING THE SHELL.
DOWNSTAND STIFFENING RCC BEAM IS MOST EFFICIENT
BECAUSE OF ITS DEPTH, BUT THIS INTERRUPTS THE LINE OF
SOFFIT OF VAULTS, FOR THIS UPSTAND STIFFENING BEAM
IS USED.
THE DISADVANTAGE OF UPSTAND BEAM IS THAT IT BREAKS
UP THE LINE OF ROOF AND NEED PROTECTIONS AGAINST
WEATHER.
24. CONSTRUCTION OF R.C.C BARREL VAULT:
EDGE AND VALLEY BEAMS:
DUE TO SELF WEIGHT AND IMPOSED LOAD THE THIN SHELL WILL TEND TO SPREAD AND ITS CURVATURE FLATTEN OUT. TO
RESIST THIS RCC EDGE BEAMS ARE CAST BETWEEN COLUMNS.
EDGE BEAMS MAY BE CAST AS DROPPED BEAMS OR UPSTAND BEAMS OR PARTIALLY AS BOTH. IN HOT CLIMATE THE
DROPPED BEAM IS USED WHEREAS IN TEMPERATE CLIMATE UPSTAND BEAM IS USED TO FORM DRAINAGE CHANNEL FOR
RAIN WATER.
IN MULTI-BAY STRUCTURES, SPREADING OF THE VAULTS IS LARGELY TRANSMITTED TO THE ADJACENT SHELLS, SO DOWN
STAND AND FEATHER VALLEY BEAM IS USED.
25. CONSTRUCTION OF R.C.C BARREL VAULT:
EXPANSION JOINTS:
THE CHANGE IN TEMPERATURE CAUSES THE
EXPANSION AND CONTRACTION IN CONCRETE
STRUCTURES, WHICH CAUSES THE STRUCTURES TO
DEFORM OR COLLAPSE.
TO LIMIT THIS CONTINUOUS EXPANSION JOINTS ARE
FORMED AT THE INTERVAL OF ABOUT 30M, ALONG THE
SPAN AND ACROSS THE WIDTH OF THE MULTI-BAY AND
MULTI-SPAN BARREL VAULT ROOFS. LONGITUDINAL
EXPANSION JOINTS ARE FORMED IN A UP STAND
VALLEY.
26. CONSTRUCTION OF R.C.C BARREL VAULT:
ROOF LIGHTS:
TOP LIGHT CAN BE PROVIDED BY DECK LIGHT FORMED IN THE CROWN OF VAULT OR BY DOME LIGHT. THE DECK LIGHT
CAN BE CONTINUOUS OR FORMED AS INDIVIDUAL LIGHTS.ROOF LIGHTS ARE FIXED TO AN UPSTAND CURB CAST
INTEGRALLY WITH THE SHELL.
ADVANTAGE OF THE SHELL IS THAT ITS CONCAVE SOFFIT REFELECTS AND HELPS TO DISPERSE LIGHT OVER AREA BELOW.
DISADVANTAGE IS THAT TOP LIGHT MAY CAUSE OVER HEATING AND GLARE.
ROOF COVERING:
SHELLS MAY BE COVERED WITH NON-FERROUS SHEET METAL, ASPHALT, BITUMEN FELT, A PLASTIC MEMBRANE OR A
LIQUID RUBBER BASE COATING.
ROOF INSULATION:
THE THIN SHELL OFFERS POOR RESISTANCE TO TRANSFER OF HEAT. THE NEED TO ADD SOME FORM OF INSULATING
LINING ADDS CONSIDERABLY TO COST OF SHELL.
THE MOST SATISFACTORY METHOD OF INSULATION IS TO SPREAD A LIGHT WEIGHT SCREED OVER THE SHELL.
DIFFICULTIES OF PROVIDING INSULATION AND MAINTING THE ELEGANCE OF CURVED SHAPE MAKES THESE STRUCTURES
LARGELY UNSUITED TO HEATED BUILDINGS IN TEMPERATE CLIMATE.
28. ADVANTAGES AND DIS-ADVANTAGES OF SHELLS:
ADVANTAGES:
1. VERY LIGHT FORM OF CONSTRUCTION. TO SPAN 30.0 M SHELL THICKNESS REQUIRED IS 60MM
2. DEAD LOAD CAN BE REDUCED ECONOMIZING FOUNDATION AND SUPPORTING SYSTEM
3. THEY FURTHER TAKE ADVANTAGE OF THE FACT THAT ARCH SHAPES CAN SPAN LONGER
4. FLAT SHAPES BY CHOOSING CERTAIN ARCHED SHAPES
5. ESTHETICALLY IT LOOKS GOOD OVER OTHER FORMS OF CONSTRUCTION
DIS-ADVANTAGES:
1. SHUTTERING PROBLEM
2. GREATER ACCURACY IN FORMWORK IS REQUIRED
3. GOOD LABOUR AND SUPERVISION NECESSARY
4. RISE OF ROOF MAY BE A DISADVANTAGE
30. CASE STUDY- SYDNEY OPERA HOUSE:
SYSTEM SPANS AND EFFECTIVE SPANS:
THE SYDNEY OPERA HOUSE SPANS UP TO 164 FEET.
THE ARCHES ARE SUPPORTED BY OVER 350KM OF
TENSIONED STEEL CABLE.
THE SHELL THICKNESS GOES FROM 3 TO 4 INCHES.
ALL SHELLS WEIGHT A TOTAL OF 15 TONS.
THIS INVOLVED LAYING THE FOUNDATIONS AND BUILDING A PODIUM 82 FEET (25 M) ABOVE SEA LEVEL. MORE THAN
39,239 CUBIC FEET (30,000 M3) OF ROCK AND SOIL WERE REMOVED BY EXCAVATORS.
THE FOUNDATION WAS BUILT ATOP A LARGE ROCK THAT SAT IN SYDNEY HARBOUR. THE SECOND STAGE SAW THE BUILDING
OF THE SHELLS, THE PODIUM STRUCTURE, THE STAGE TOWER, AND THE NECESSARY MACHINERY.
CABLE BEAMS WERE BUILT AND REINFORCED BY STEEL CABLES TO RELEASE THE STRESS OF THE WEIGHT. THE STRENGTH OF
THE CABLES WAS TESTED BY LOADING ADDITIONAL WEIGHTS. WHEN THE BUILDERS WERE SATISFIED THAT THE CABLES
WOULD SUPPORT, THE BEAMS WERE MADE EXTENDABLE BY OTHER BEAMS.
31. CASE STUDY- SYDNEY OPERA HOUSE:
SYSTEM SPANS AND EFFECTIVE SPANS:
THE "SHELLS" WERE PERCEIVED AS A SERIES OFPARABOLAS SUPPORTED BY PRECAST CONCRETE RIBS. THE FORMWORK FOR
USING IN-SITU CONCRETE WOULD HAVE BEEN PROHIBITIVELY EXPENSIVE, BUT, BECAUSE THERE WAS NO REPETITION IN ANY
OF THE ROOF FORMS, THE CONSTRUCTION OF PRE-CAST CONCRETE FOR EACH INDIVIDUAL SECTION WOULD POSSIBLY HAVE
BEEN EVEN MORE EXPENSIVE.
THE DESIGN TEAM WENT THROUGH AT LEAST 12 ITERATIONS OF THE FORM OF THE SHELLS TRYING TO FIND AN
ECONOMICALLY ACCEPTABLE FORM (INCLUDING SCHEMES WITH PARABOLAS, CIRCULAR RIBS AND ELLIPSOIDS) BEFORE A
WORKABLE SOLUTION WAS COMPLETED. IN MID-1961, THE DESIGN TEAM FOUND A SOLUTION TO THE PROBLEM: THE SHELLS
ALL BEING CREATED AS SECTIONS FROM A SPHERE. THIS SOLUTION ALLOWS ARCHES OF VARYING LENGTH TO BE CAST IN A
COMMON MOULD, AND A NUMBER OF ARCH SEGMENTS OF COMMON LENGTH TO BE PLACED ADJACENT TO ONE ANOTHER,
TO FORM A SPHERICAL SECTION.
33. CASE STUDY- SYDNEY OPERA HOUSE:
1. SYDNEY OPERA HOUSE STEEL REINFORCING
3. SYDNEY OPERA HOUSE ON COMPLETION OF PODIUM 2
2. SYDNEY OPERA HOUSE ON COMPLETION OF PODIUM 1
4. SYDNEY OPERA HOUSE SHELL RIBS
34. CASE STUDY- SYDNEY OPERA HOUSE:
FINISHES:
ACTUAL CLAY, BRICK, AND STONE VENEER
GRANITE OR MARBLE CLADDING
EXPOSED AGGREGATE FINISH
SAND BLASTED FINISH
FORM LINER PATTERNS
THE SYDNEY OPERA HOUSE USES WHITE GLAZED GRANITE TILES.
1,056,000 TILES WERE USED TO COVER THE MASSIVE STRUCTURE.