Name: Umaru Mohammed
TABLE OF CONTENT
INTRODUCTION ... 5 STRUCTURAL SYSTEMS ... 5 FOUNDATION SYSTEMS ... 6 SHALLOW FOUNDATION ... 6 DEEP FOUNDATIONS ... 6BEARING WALL SYSTEM ... 7
APPLICATION ... 7
POST AND LINTEL ... 8
PRECAST BUILDING SYSTEM ... 9
TENDENCIES IN PRECAST CONCRETE ... 11
Advantages of Precast Concrete ... 11
Disadvantage of precast concrete ... 11
CAST-IN-PLACE CONCRETE SYSTEM ... 11
CONCRETE... 12
COMPOSITION OF CONCRETE ... 12
The advantages of concrete are; ... 13
Its major disadvantages are; ... 13
STEEL ... 13
The advantages of steel are ... 13
WOOD ... 14
Major advantages of wood are: ... 14
Major disadvantages are: ... 14
Composite of wood ... 15
BRICK ... 15
Kind of brick shapes ... 16
Advantages of brick include ... 16
IRON ... 18
The advantages of iron are ... 18
Its disadvantages are ... 18
STONE... 19
Types of stone ... 19
GRANITE: ... Error! Bookmark not defined. LIMESTONE: ... 20
MARBLE: ... 20
The advantages of stone are ... 21
Its disadvantages include ... 21
MOTAR ... 22
SPACE STRUCTURAL SYSTEMS ... 24
General Introduction ... 24 FRAMING SYSTEM ... 24 Interior partitions... 25 Balloon framing: ... 25 Platform framing: ... 26 Truss Construction ... 26 Advantages of truss: ... 26 Types of Trusses ... 27
Heavy Timber Truss Systems ... 27
Characteristics ... 27
Light Weight Wooded Truss Systems ... 28
Metal Truss Systems ... 28
Types of truss designs ... 29
ARCHES ... 32
Construction process ... 32
Types of arch ... 32
Other types ... 34
VIERENDEEL GIRDERS ... 34
Characteristics ... 35
Schematic forms of vierendeel girders and frames ... 36
Features of vierendeel girder at Yale University ... 36
INTRODUCTION
Generally, structure is a necessary part of architecture; with reason being that it ensures the stability of buildings. In engineering design process, structural members should be design to enable the resolution and transfer of forces to the ground. This is achieved by various structural systems, depending on what kind of structure is to be built. Some of these structural systems include;
Foundation systems Bearing wall systems
STRUCTURAL SYSTEMS
Skeleton Structures systems Compound systems
Folded Plates and shells system Tensile Structures
Space structures
FOUNDATION SYSTEMS
Foundation design in the past has always been very much a matter of inspired guesswork on a background of past experiences. Ancient methods were pathetically crude. Winchester cathedral was built originally on a foundation of short Oak piles and bundles of wattles in a bed of peat. This has survived for 750 years due to the
preservative qualities of the peat. It was until the spread of rational thought processes in France in the 18th century that led to the development by coulomb of his theory of earth pressure against retaining walls. The Montauk building (10 storeys) was the first to use a steel grillage foundation and the stock exchange building 1894 became the first to use large diameter concrete piles.
Except in few cases where a level bed of rock is sufficient foundation, concrete is the principal material use for foundations, with some steel for reinforcement. The
stability of the building depends on its foundation thus it’s important to ensure that these materials are of satisfactory qualities.
Foundations are generally broken into two categories: Shallow foundations
Deep foundations.
SHALLOW FOUNDATION
Shallow foundation are usually embedded a meter into the soil. One common type is the spread foundation which consists of strips or pads of concrete (or other materials) which extend below the frost line and transfer the weight from wall and columns to the soil or bedrock. Another common type is the slab-on-grade foundation where the weight of the building is transferred to the soil through a concrete slab placed at the surface.
DEEP FOUNDATIONS
Deep foundations are used to transfer a load from a structure through an upper weak layer of soil to a stronger deeper layer of soil. There are different types of deep foundations including piles, impact driven piles, drilled shafts, caissons, piers, and earth stabilized columns. The naming conventions for different types of foundations vary between different engineers. Historically, piles were wood, later steel,
reinforced concrete, and pre-tensioned concrete.
condition. This kind of foundation is call Earthquake-protective foundations.
BEARING WALL SYSTEM
A load-bearing wall or bearing wall, is one in which a wall of a structure bears the weight and force resting upon it, conducting the vertical load from the upper
structure to the foundation. Load-bearing walls are one of the earliest forms of construction.
APPLICATION
Depending on the type of building and the number of stories, load-bearing walls are gauged to the appropriate thickness to carry the weight above it. Without doing so, it is possible that an outer wall could become unstable if the load exceeds the strength of the material used, potentially leading to the collapse of the structure
POST AND LINTEL
• This is the simplest of structural systems.
• It is made up of a vertical column that transfers the load of the horizontal lintel to the ground.
• This is the main construction system of ancient Egyptian temples and Greek architecture.
• It is also the most common form of modern construction
.
• Other available structural systems include shells, air supported structures, cable supported structures etc.
Every construction material & system has its own characteristics which to a greater or less extend influence the layout, span length, construction depth, stability system, etc. This is also the case for precast concrete, not only in comparison to steel, Wood, & masonry structures, but also with respect to cast in-place concrete.
PRECAST BUILDING SYSTEM
Architectural precast concrete provides architects with an exciting medium when designing facades for a wide range of buildings, from healthcare facilities to shopping malls, commercial office buildings to sports stadiums. Most of its members include;
• Precast concrete frame • Precast concrete wall • Precast concrete floor
PRIMARY FUNCTIONS SECONDARY FUNCTIONS Keep water out
prevent air leakage control light
Control radiation of heat control conduction of heat control sound
Resist wind forces control water vapour adjust to movement thermal & moisture expansion/contraction structural movements resist fire Weather gracefully Easy to install
Precast concrete frames involve an entire structure being fabricated off-site. In addition, structural components can be supplied for incorporation into a structure on- site. Frames can simultaneously achieve both structural and decorative design
requirements - a wide variety of mixes, colours and finishes can be accommodated. Precast wall are used for internal & external walls, lift shafts, central cores etc. Precast wall systems are mostly used in domestic construction, both for individual housing & for apartments. The precast walls can be load bearing or only partition
walls. Precast walls offer the advantage of speed of construction, smooth surface finishing, acoustic insulation & fire resistance.
Likewise, precast concrete floor can either be; • Hollow core floors
• Ribbed floors
• Concrete roof elements • Massive slab floors
TENDENCIES IN PRECAST CONCRETE
Structural efficiency
Flexibility in use
Optimum use of
materials Speed of
construction Quality
consciousness
Adaptability
Protection of the environment
Advantages of Precast Concrete
less expensive than real brick.
does not require an extensive footing like a real masonry wall. Can be reset should it ever shift.
More durable than real masonry - no mortar joints to let water in. Installs quickly and easily - most can be done in one day.
Maintenance free - No need to paint or periodically replace slats as you would with wood fences.
Disadvantage of precast concrete
System building is less flexible in its design concept than purpose-mode structures
Most design briefs can be fulfilled without too much modification to the original concept
Structural connection between the precast concrete units can present both design & contractual problems
CAST-IN-PLACE CONCRETE SYSTEM
Cast-in-place concrete consists of concrete which is poured into forms, onto decking, or on the ground at its final location in the building. Although cast-in-place concrete has many typical uses (such as slabs on grade or topping for roof and floor decks), this use of concrete is probably the most expensive and the
slowest of structural systems available. Cast-in-place concrete can be a
competitive solution for high-rise buildings if the structural components also are used for floor, ceiling and wall components.
CONCRETE
Romans were the first during civilization to use concrete. They used it to achieve very big structures with huge interiors. Use of concrete was discontinued in the middle Ages. Came into use again after 1824 when Portland cement was developed. The addition of steel reinforcement that followed this development increased the use of concrete as a construction material.
COMPOSITION OF CONCRETE
The main composition of concrete is; a) Cement
b) Aggregate c) Sand
d) Water
The advantages of concrete are;
its fire resistance,
inexpensive manufacturing process, durable nature,
its structural versatility,
High compressive strength and Ability to pre-cast it
Its major disadvantages are;
The fact that casting must be controlled, and so it cannot be mixed far away from the site.
It is also subject to rapid deterioration in hostile environments
STEEL
Steel became popular after 1856, when H. Bessemer developed a process for introducing carbon into the smelting process. Steel, as used in a structural system, typically consists of steel beams, columns and floor and roof decks.
Typical shapes
Angle
Structural steel shape resembling L. Used in trusses and built-up girders. Channel
Structural steel shape which has a cross-section resembling [. Used in trusses and built- up girders.
Plate
Sheet steel with a width of more than eight inches, with a thickness ranging from one quarter of an inch to more than one.
Flat-rolled steel
Reinforcing Bar (Rebar) Sheet
Its extreme strength and rigidity,
Its superior joining capabilities and the fact that you can have a highly controlled manufacturing process for it.
Structural steel generally is more economical as a framing system than concrete.
Structural steel typically takes less time than concrete to fabricate and erect.
Steel is a more economical means of spanning open spaces such as dayrooms. Steel is a very durable material if detailed properly.
One disadvantage is the need to fireproof structural members in many instances, although this cost alone doesn't make it more expensive than concrete. It becomes more expensive when the fireproofing also must be covered by expensive finish systems that are accessible to inmates.
The cost can be more than concrete. Moreover, it liquefies when subjected to very high temperature.
WOOD
This structural system consists of wood columns, beams and framing for floors, roofs and walls, as commonly found in smaller commercial or residential buildings of up to three floors
.
It’s
among earliest materials used in construction Early stone age people built huts with wood
Currently used for Post and Beam and frame construction Also used for interior decoration and furnishing
Major advantages of wood are:
its compressive and tensile strength, the ease in shaping and carving it, its lightweight and
abundant supply
Major disadvantages are:
its inflammable nature,
its subjectivity to rot and insect damage and the limitation in its length
Composite of wood
Element % of dry weight
Carbon 49
Hydrogen 6
Oxygen 44
Nitrogen Slight amount
Ash 0.2 – 1.
BRICK
Brick is used in locations where there are no wood and stone. Romans were among the first civilizations to use brick extensively. They also used brick as a formwork for concrete.
Commercial mass production of brick introduced in 1628 made brick the predominant building material in England.
Manufacturing processes for brick
Various process are been used for brick manufacture, some of which are; • Stiff Mud - Extrusion Process
Kind of brick shapes
Advantages of brick include
lightweight,
its uniform size, density and color, and
the fact that it can be manufactured in a variety of colors, textures and sizes
Disadvantages include
the labor intensive installation process,
its ineffectiveness in tension and
Mortar used in bonding brick is usually the weakest element and vulnerable to water penetration.IRON
• Iron became popular in after Thomas Darby discovered in 1777 that high temperature causes iron to liquefy and become malleable.
• The first architectural applications were in bridges and railroads.
• Cast iron (2-4% carbon) was used for structural applications and wrought (0.1% carbon) iron for ornamental work.
The advantages of iron are
– its high strength, – light nature and
– mass production potential
Its disadvantages are
– its subjectivity to corrosion and – its brittle nature
STONE
The Ancient Egyptians used stone extensively. Stone was also the favored building material of the Mycenaean and Greek people. Stone construction varies by location depending on the type of stone available.
Types of stone
The types of stone in construction are; Granite Limestone Marble Travertine Sandstone Bluestone Slate. GRANITE:
A very hard, crystalline, igneous rock, gray to pink in color, composed of feldspar, quartz, and ferromagnesian materials. Black "granites" are similar to true "granites" in structure and texture, but are composed of different minerals (basalt, gabbros, and diabase).
LIMESTONE:
A sedimentary rock composed primarily of calcite or dolomite. The varieties of limestone used as dimensional stone are usually well consolidated and exhibit a minimum of graining or bedding direction.
MARBLE:
A metamorphic (re-crystallized) limestone capable of being polished and used for architectural and ornamental purposes. The color varies including white, black, yellow, red, and green, and frequently beautifully veined or clouded.
The advantages of stone are
– its compressive strength,
– its ornamental and sculptural value, and – its durability
Its disadvantages include
– Poor tensile strength, – Excessive weight, and
– High cost in quarrying and finishing
Other materials that are commonly used in contemporary buildings include: – aluminium, – glass, – plastics, paper, – lead, – synthetics, – canvass,
Compressive Strength & Density of building materials Brick 2500 psi 100-140 pcf CMU Limestone Sandstone Marble Granite 1900 psi 3000 psi 4000 psi 9000 psi 15,600 psi 75-135 pcf 130-170 pcf 140-165 psf 165-170 pcf 165-170 pcf
MOTAR
It’s a bonding material like cement as earlier mentioned above. It is divided into four categories;
Type M Type S Type N Type O
Functions:
Bonding Sealing against Air and Water Accommodating Small Movements Levelling
Proportion & Strength Specifications Mortar Portland Cement Hydrated Lime Aggregate Strength M 1 1/4 S 1 1/4 ~ 1/2 N 1 1/2 ~ 1 1/4 O 1 1 1/4 ~ 2 1/2 2 1/4 ~ 3 2 1/4 ~ 3 2 1/4 ~ 3 2 1/4 ~ 3 2500 psi 1800 psi 750 psi 350 psi
SPACE STRUCTURAL SYSTEMS
General Introduction
The term 'space structure' refers to a structural system that involves three dimensions. This is in contrast with a 'plane structure', such as a plane truss, that involves no more than two dimensions. Space structures, encompasses
grids,
barrel vaults,
domes, towers, cable nets, membrane systems,
foldable assemblies and Tensegrity forms.
Space structures covers enormous shapes and are constructed using different materials such as; steel, aluminium, timber, concrete, fibre reinforced composites, glass, or a combination of these.
Space structures may be divided into three categories, namely,
'lattice space structures' that consist of discrete, normally elongated, elements, 'continuous space structures' that consist of components such as slabs, shells,
membranes, and
'Biform space structures' that consist of a combination of discrete and continuous
parts.
Space structures are been classified into; frames, trusses, arches, vierendeel girders.
FRAMING SYSTEM
Framing( light frame construction), is a building technique based around structural members, usually called studs, which provide a stable frame to which interior and
exterior wall coverings are attached, and covered by a roof comprising horizontal ceiling joists and sloping rafters (together forming a truss structure) or manufactured
pre-fabricated roof trusses, all of which are covered by various sheathing materials to give weather resistance.
When steel is used it’s called steel frame system comprising of vertical steel Column and horizontal I-beams,constructed in a rectangular grid to support the floors, roof and walls of a building which are all attached to the frame. The development of this
A two-story wooden-frame house under construction
Steel framed housing development.
Multiple parts of the building could be framed, some of which include, Wall
Conner Exterior wall Interior partitions Lintels (headers)
The kinds of framing system commonly used nowadays are;
Balloon framing:
Balloon framing is a method of wood construction used primarily in Scandinavia, Canada and the United States.It utilizes long continuous framing members (studs) that run from sill plate to eave line with intermediate floor structures nailed to them.
Though wood is a conventional material in this kind of area and readily available however, as a construction method the Balloon framing has several disadvantages
1. The creation of a path for fire to readily travel from floor to floor.
2. The lack of a working platform for work on upper floors. The requirement for long framing members.
3. In certain larger buildings, a noticeable down-slope of floors towards central walls, caused by the differential shrinkage of the wood framing members at the perimeter versus central walls.
Platform framing:
The framed structure sits atop a concrete (most common) or treated wood foundation. Mostly wood is used. However, wood isn’t the only material being imposed, metal plates also are used in some areas.
Light-gauge metal stud framing
Light-frame buildings are often erected on monolithic concrete slab foundations that serve both as a floor and as a support for the structure. Other light-frame buildings are built over a crawlspace or a basement, with wood or steel joists used to span between foundation walls, usually constructed of poured concrete or concrete blocks.
Truss Construction
Until the 1960s, almost all truss systems were two-dimensional. They had developed from timber roofs, which themselves had evolved from a basic triangular arrangement to more complex shapes.
Trusses are defined as structural systems in which the members are interlinked so that they are only subject to axial compressive or tensile forces. A truss is structural members joined together to form ridged frame work of a structure.
Advantages of truss:
Over 60% of today’s structures use truss systems Truss material is lighter and less expensive Can be found in roof and floor systems
Trusses allow for larger openings in areas of a structure Easier and safer to handle during construction
Types of Trusses
Heavy Timber Floor and Roof Trusses
Light timber Floor and Roof trusses most common! Metal Floor and Roof Truss systems
Heavy Timber Truss Systems
Characteristics
Usually used to create large clear areas like Cathedral Ceilings Bolts are commonly used to connect truss members
Light Weight Wooded Truss Systems
Characteristics Made from 2x4, 2x6, and 2x8 sized lumber Found mostly in single family dwelling
Uses the lightest weight lumber necessary to support the anticipated load Gusset plates are usually used to connect truss system members.
Metal Truss Systems
Characteristics
Much stronger than Timber
Most common in commercial structures
Can be found in combination with other materials May use cable in the truss web.
Heavy metal truss
Types of truss designs
Triangular Trusses
Are the most common trusses used in single-family dwellings? Triangular trusses provide a peaked roof
Scissor Trusses
Are common in construction with cathedral ceilings. They are often found in churches.
Parallel Chord Trusses
Provide a flat roof or floor.
The top and bottom chords are parallel.
They are commonly used in single-family dwellings, row houses, apartment buildings, and smaller office buildings.
Bowstring Trusses
Get their name from the curved shape of the top chord.
Parapet walls may hide the curved roofline on large commercial buildings.
They are used in place of support columns to provide open floor space under the truss. Forms of trusses
ARCHES
An arch is a structure that spans a space while supporting weight (e.g. a doorway in a stone wall). Arches appeared as early as the 2nd millennium BC in Mesopotamian brick architecture, but their systematic use started with the Ancient Romans who were the first to apply the technique to a wide range of structures.
Construction process
An arch requires all of its elements to hold it together, raising the question of how an arch is constructed. One answer is to build a frame (historically, of wood) which exactly follows the form of the underside of the arch. This is known as a centre or
centering. The voussoirs are laid on it until the arch is complete and self-supporting. For an arch higher than head height, scaffolding would in any case be required by the
builders, so the scaffolding can be combined with the arch support.
Types of arch
Triangular arch
Round arch or
Semi-circular arch Segmental arch
Unequal round arch or Rampant round arch
Lancet arch Equilateral pointed arch
Shouldered flat arch Three-foiled cusped arch
Horseshoe arch Three-centred arch Elliptical arch Inflexed arch
Ogee arch Reverse ogee arch Tudor arch
Catenary or Parabolic arch
Other types
A blind arch is an arch in filled with solid construction so it cannot function as a window, door, or passageway.
A dome is a three-dimensional application of the arch, rotated about the center axis. Igloos are notable vernacular structures making use of domes.
Natural rock formations may also be referred to as arches. These natural arches are formed by erosion rather than being carved or constructed by man. See Arches National Park for examples
A special form of the arch is the triumphal arch, usually built to celebrate a victory in war. A famous example is the Arc de Triumphed in Paris, France.
A vault is an application of the arch extended horizontally in two dimensions; the groin vault is the intersection of two vaults.
VIERENDEEL GIRDERS
Characteristics
They occupy large horizontal span. They don’t require bracings
Schematic forms of vierendeel girders and frames
Vierendeel facade
Vierendeel element
Cross section
REFERENCES
Essence book on building- general editor J.H Cheetham, A.R.B.A ( V.C
launder)
Reinforced concrete fundamentals (Phil M. Ferguson)
o
4
thEdition S.I version
Building Construction Materials and types of Constructions
o
Huntington Mickadeit
o
5
thedition
o
www.shilstone.com
Bowyer, J. L., and R. L. Smith, 1998. The Nature of Wood and Wood
Products, University of Minnesota, Forest Products Management
Institute, Minneapolis, MN, 1998.
Steel structures (design and behaviour) 2
ndedition
o
Salmon Johnson.
National Design Specification for Wood Construction, American Forest
and Paper Association,
o
Washington, DC, 1997. http://www.cispi.org/handbook.htm
http://www.wsdot.wa.gov/fasc/EngineeringPublications/Manuals/S
S2004.PDF
[1] International Journal of Space Structures (currently in its twelfth
volume), Editors: H Nooshin and Z S Makowski, Published by
Multi-Science Publishing Co Ltd, 107 High Street, Brentwood, Essex CM14
4RX, UK
[2] Makowski, Z S. Steel Space Structures, Michael Joseph Ltd,
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