post lintel structure for architects
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Post lintel structure is a simple construction method that uses vertical posts or columns supporting a horizontal beam or lintel. It has been commonly used for centuries to support weight above openings. The key components are the post, which must support the lintel without crushing, and the lintel, which must bear loads without deforming or breaking. Materials used include stone, wood, steel and concrete. Advantages include faster construction and better insulation, while disadvantages include limited span and load capacity. Proper design of foundations, connections and consideration of forces like tension and compression are important for structural integrity.
post lintel structure for architects
- 1. Report on Post Lintel Structure
- 2. CONTENT Introduction -01 Building as Structure -02 Classification of structural System -03 General Properties -04 Definition -05 History -06 Concept -07 Meterals -08 Post -09 Lintel -10 Foundation-11-12 Span Material Relations-13 Cantilever Beans-14 Failures-15 CONTENT 00 Failures-15 Advantage-16 Disadvantage-17 Force on structure-18 Load-19-21 Load & support in conostuction -22 THERMAL MOVEMENT OF STRUCTURAL STEEL-23 Other Structure & bridge structure-24-27 Modern Uses -28 Examples - 29-31 Conclusion -32
- 3. INTRODUCTION Building systems can be post-and-lintel, vaulted or internal structures. There are several ways to build according to the type and location. How to build depends on the technological level of the community that builds and the needs they manifest. In any case, the construction system uses by a community reflects part of his personality as the building is a way to transform the environment adapted to the human needs. Ever since man left the shelter that provided the cave, until now, there have been three different building systems: lintel, domed and internal structures. The building method of post and lintel has been used for centuries. All structural openings have evolved from this system, which is seen in pure form only in framed structures, because the posts of doors, windows, ceilings, and roofs normally form part of the wall. Post and lintel construction is recognized by its simple vertical and horizontal design, in which a pair of vertical supports are set in the ground or a foundation, and a horizontal structure is balanced on top of them. 01
- 4. Building as a structure Building as a structure : A building is a structure, or a system. On a system of organized elements, which are these elements ? A building can serve as a structure in many ways, depending on the purpose of it to the human been, the place were it is built or to understand reason. - Skin - Importance of the Location. Landmark -Tall buildings: feet, torso, head - Patrimonial structure -Shelter -Shell 02
- 5. Classification of the Structural Systems Classification of the Structural Systems: MASSIVE STRUCTURES: They are those in which the resistance and the stability are obtained by means of the mass, even though the completely solid structure not. RETICULAR STRUCTURES: It consists of a network of assembled elements SUPERFICIAL STRUCTURES: They can have high performance due to his double function like structure and surrounding, they can be very stable and strong. SYSTEMS FORMED BY BARS. With adjustments of bars very diverse structural schemes can form, of which I could become one first subdivision between triangular adjustments, type armor, and adjustments type frame. In the first external loads they resist essentially by axial forces in the members. In the adjustments nontriangulados, or type frame, the transmission of the loads implies the appearance of sharp flexion and. SYSTEMS WITH PLATES. By means of vertical adjustments (walls) and horizontals (slabs) systems of diverse characteristics can be formed, those that in general can be denominated type drawer. The over position of plates simply supported in a single direction and walls, Integra a system equivalent to the post and the threshold and that has similar limitations. The lack of continuity in the supports makes very vulnerable before accidental actions that can introduce vertical tensions or sharp efforts in the connection. 03
- 6. The general properties The general properties: Form: natural, remolded or reconstituted. Weight : like contributor to the gravitational loads of the structure. Fire resistance: combustion, conductivity, point of fusion and general behavior of high temperatures. Coefficient of thermal expansion: related to the dimensional changes due to the temperature variations. Durability: resistance to the climate, insects and wearing downs. Appearance: natural or modified. 04
- 7. Definition Definition Is a simple construction method using a lintel, header, or architrave as the horizontal member over a building void supported at its ends by two vertical columns, pillars, or posts. This architectural system and building method has been commonly used for centuries to support the weight of the structure located above the openings created by windows and doors in a bearing wall. A structure is formed generally by an adjustment of basic elements. The adjustment must take advantage of the peculiar characteristics, each element obtain the most efficient form of the global structural system, fulfilling the restrictions imposed by the operation of the construction and many other aspects. 05
- 8. History HistoryI From prehistoric times to the Roman Empire, the post and lintel system was the root of architectural design. The interiors of Egyptian temples and the exteriors of Greek temples are delineated by columns covered by stone lintels. The Greeks opened their interior spaces by substituting wooden beams for stone, since the wood required fewer supports. The development of the arch and vault challenged the system but could not diminish its importance either in masonry construction or in wood framing, by its nature dependent on posts and beams . Ancient Egyptian, Greek, and Roman architects made extensive use of Post- and-lintel construction to support the roofs of temples and public places. Such ancient structures as Stonehenge, in Britain, were constructed on the post-and-lintel system, which was the basis of architecture from prehistoric to Roman times. The interiors of Egyptian temples and the exteriors of Greek temples are delineated by columns covered by stone lintels. The Greeks substituted wooden beams for stone because the wood required fewer supports and opened up the interior spaces. One of the earliest and most renowned post and lintel example is the prehistoric Stonehenge monument in England, where massive stone blocks were placed in a circle in the support-and-overhead design. Pure post and lintel construction also can be found in a variety of early shelters, including huts, cottages and stables. The Romans developed a variation of post and lintel construction with the arch, which added stability and support, and by the Catholic Church in Europe with the introduction of buttresses to support massive cathedral walls . 06
- 9. Concept Concept Post and lintel, or in contemporary usage Post and beam, is a simple construction method using a lintel, or header as the horizontal member over a building void supported at its ends by two vertical columns, pillars, or posts. This architectural system and building method has been commonly used for centuries to support weight, such as a roof or deck, depending on the vertical posts it rests on. It can support a huge amount of weight, and is effective for reinforcing tall buildings or heavy structures. The post refers to the vertical support, which is paired with an identical support to form the full design. Posts can be columns, poles or beams, modified to meet as architectural designs. There are two main force vectors acting upon the post and lintel system: weight carrying compression at the joint between lintel and post, and tension induced by deformation of self-weight and the load above between the posts. The two posts are under compression from the weight of the lintel (or beam) above. . 07
- 10. Material Material. The posts must support the lintel and its loads without crushing or buckling. Post material must be especially strong in compression . Post and lintel construction can incorporate wood, metal and stone. Stone has this property and is more versatile in its use as a post than as a lintel. Under heavy loads, stone is superior to wood but not to iron, steel, or reinforced concrete. When used in doorways, wood and steel are the most common materials. Depending on building requirements and ordinances, the supports in windows may be made of plastic or fiberglass, while wood or metal form the surrounding frame. Masonry posts, including those of brick, may be highly efficient, because loads compress the joints and add to their cohesiveness .The most important detail about post and lintel construction is the pieces must fit together exactly, so they are often prefabricated in mills and shops, and then assembled on-site. . 08
- 11. Post and lintel system Post and lintel system : Two upright members (post, columns, piers) Third member (lintel, beam, girder, rafter) The basis for the evolution of all openings To support the weight of the structure located above the openings Post : The job of the post is to support the lintel and its loads without crushing or buckling. Failure occurs, as in lintels, from excessive weakness or length, but the difference is that the material must be especially strong in compression. Stone, which has this property, is more versatile as a post than as a lintel; under heavy loads it is superior to wood but not to iron, steel, or reinforced concrete. Masonry post, including those of brick, may be highly efficient, since the loads compress the joints and add to their cohesiveness. Although monolithic stone columns are used, they are extravagant to produce for large structures, and columns are usually built up of a series of cylindrical blocks called drums. The job of the post is to support the lintel and its loads without crushing or buckling. Masonry post, including those of brick, may be highly efficient, since the loads compress the joints and add to their cohesiveness. 09
- 12. Post and lintel system Beam: The job of the beam or lintel is to bear loads that rest on it, also includes its own wheigth -The beam has to be able to do this without deformor break Made of wood, stone, steel or reinforced or pre-tensioned concrete Stone lintels must be short, weak in bending Materials strong in bending, bigger span, greater openings Mansory lintels are inefficient cohesiveness of mortar 10 load BEAM or LINTEL
- 13. Foundation Foundation: A foundation is a structure that transfers loads to the ground. Foundations are generally broken into two categories: shallow foundations deep foundations. Shallow foundations A shallow foundation is a type of foundation which tranfers building loads to the earth very near the surface, rather than to a subsurface layer or a range of depths as does a deep foundation. Shallow foundations include spread footing foundations and slab-on grade foundations Deep foundations.: A deep foundation is a type of foundation. Deep foundations are distinguished from shallow foundations by the depth they are embedded into the ground. There are many reasons why someone would recommend a deep foundation over a shallow foundation, but some of the common reasons are very large design loads, a poor soil at shallow depth, or site constraints (like property lines). There are different terms used to describe different types of deep foundations including piles. 11
- 14. Foundation Retaining wall : A retaining wall is a structure that holds back earth from a building or other structure. Retaining walls stabilize soil and/or rock from downslope movement or erosion and provide support for vertical or near-vertical grade changes. Cofferdams and bulkheads, structures that hold back water, are sometimes also considered retaining walls. Retaining walls are generally made of masonry, stone, brick, concrete, vinyl, steel or timber. They also decompose over time. 12
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- 17. Failure occurs when the material is to weak or the span is to long to support the load. This makes the beam bend or break. This aspect combined with others can cause many structural accidents, destroying the structure like a house of cards 15
- 18. Advantage: Building Time Homes constructed with a post and beam construction method can usually be assembled quicker that other types of construction. The frame and insulated wall sections of a home are usually preassembled in a shop and then transported to the site where the home is built. This allows the mortise and tenon joints to be premilled at a remote location, saving time at the building site. Aesthetics Post and beam construction is generally considered to be more aesthetically pleasing than other types of construction because the wood is exposed on both the interior and exterior of the home. This is a subjective judgment that is obviously up to the individual viewing the home. Fire Resistance Some building codes classify building materials into five different types based on the combustibility or fire resistance capability. Post and beam construction materials are classified as Type IV material, and the construction method is known for delaying the spread of exterior fires into the interior 16 Advantage Energy Efficiency The post and beam construction method is considered more energy efficient than houses constructed using alternative methods because it is easier to insulate the home. In a post and beam construction, cold air can penetrate only through the joints in between the individual timber beams. The insulation used has less of a cold air flow to protect against. A home constructed with wood studs nailed together and then covered with exterior and interior panels allows cold air to infiltrate anywhere along the frame, making it more difficult to insulate. Online References Many online sites exist to provide information on post and beam homes. Some of the sites include the Timber Frame Forum, and the Timber Engineering Reference Center. The URLs for these two sites are in the Resources section of this article. Open Living Spaces Homes that are constructed using post and beam methods have larger interior living spaces than houses constructed using alternative methods. This is because the timber frames are strong enough to avoid the use of interior load-bearing walls.
- 19. Disadvantage: The biggest disadvantage to a post and lintel construction is the limited weight that can be held up, and the small distances required between the posts. The tension induced by deformation of self-weight and the load above between the posts. 17 Disadvantage
- 21. 19 Load Gravity Loads Gravity loads include all forces that are acting in the vertical plane (see Figure 2). These types of forces are commonly broken down into dead loads and live loads in a uniform pounds per square foot loading nomenclature. Dead loads account for the anticipated weight of objects that are expected to remain in place permanently. Dead loads include roofing materials, mechanical equipment, ceilings, floor finishes, metal decking, floor slabs, structural materials, cladding, facades and parapets. Live loads are those loads that are anticipated to be mobile or transient in nature. Live loads include occupancy loading, office equipment and furnishings. Horizontal Loads Forces created by wind or seismic activity are considered to act in the horizontal plane. While seismic activity is capable of including vertical forces, this discussion will be based only on horizontal forces. The majority of this section will address wind forces and how they are transferred to the primary structural systems of the building (see Figure 3).
- 22. 20 Load Seismic Seismic activity induces horizontal forces, and at times, vertical loads. The discussions in this publication will focus on horizontal forces imposed during seismic activity. Forces created during a seismic event are directly related to weight or mass of the various levels on a specific building. During seismic activity horizontal diaphragms behave like wind load transfers with respect to the primary lateral load resisting systems. However, the induced forces are much more sensitive to the shape of the building and the positioning of the lateral load resisting systems. It is advantageous to consider a very regular building plan in areas of the country with significant seismic activity.
- 23. 21 Load Braced Frames Cross Bracing Perhaps the most common type of braced frame is the cross-braced frame. A typical representation of a crossbraced frame is shown in Figures 5 and 6. Figure 5 shows a typical floor framing plan with cross bracing denoted by the dashed-line drawn between the two center columns. The solid lines indicate the floor beams and girders. A typical multi-floor building elevation with cross-braced bays beginning at the foundation level is shown in A Figure 6. While only one bay is indicated in Figure 6 as having cross bracing, it must be understood that many bays along a given column line may be necessary to resist the lateral loads imposed on a specific structure. One or more column lines having one or more bays of cross bracing may be necessary as well. It is important to establish early on in the development of any project the location of braced bays. These considerations are typical to all of the braced frames discussed in this publication.
- 24. 22 Load & support in conostuction Lintel Beam Girder Rafter Post Columns Piers Simple construction method Upright members: posts, columns or piers Hold a third member horizontally: lintel, beam, girder or rafter. In this system acts two forces, compression and tension. Post and lintel construction-pieces must fit together exactly.
- 25. 23 THERMAL MOVEMENT OF STRUCTURAL STEEL THERMAL MOVEMENT OF STRUCTURAL STEEL Change in steel length = (0.0000065) × (Length of steel) × (Temperature differential) If a building with a large rectangular floor plan is exposed to a temperature differential of 60° Fahrenheit, andhas expansion joints at every 200 ft in the long direction (see Figure 15), the horizontal movement in that direction will be as follows: Change in steel length = (0.0000065) × (200 ft) × (60° Fahrenheit) = 0.08 ft = 0.94 in. Basic Vibration Terminology Dynamic Loadings. Dynamic loadings can be classified as harmonic, periodic, transient and impulsive as shown in Figure 18. Harmonic or sinusoidal loads are usually associated with rotating machinery. Periodic loads are caused by rhythmic human activities such as dancing and aerobics, and by impactive equipment. Transient loads occur from movement of people and include walking and running. Single jumps and heel-drop impacts areexamples of impulsive loads. Period and Frequency. Period is the time, usually in seconds, between successive peak excursions in repeating
- 27. 25 Oters structures beam bridge: A beam bridge is a rigid,, horizontal structure that rests on two end supports, and carries traffic loads by acting structurally as a beam. It is a direct descendant of the log bridge, now more normally made from shallow steel "I". It is frequently used in pedestrian bridges and for highway overpasses and flyovers. As is its ancestor, this bridge is in structural terms the simplest of the many bridge types. cantilever bridge A cantilever bridge is a bridge built using cantilevers: structures that project horizontally into space, supported on only one end. For small footbridges, the cantilevers may be simple beams; however, large cantilever bridges designed to handle road or rail traffic use trusses built from structural Steel or box girders built from prestressed concrete. The steel truss cantilever bridge was a major engineering breakthrough when first put into practice, as it can span distances of over 1500 feet, and can be more easily constructed at difficult crossings by virtue of using little or no falsework. arch bridge An arch bridge is a bridge with abutments at each end shaped as a curved arch. Arch bridges work by transferring the weight of the bridge and its loads partially into a horizontal thrust restrained by the abutments at either side. A viaduct may be made from a series of arches.
- 28. 26 Oters structures Arch bridge An arch bridge is a bridge with abutments at each end shaped as a curved arch. Arch bridges work by transferring the weight of the bridge and its loads partially into a horizontal thrust restrained by the abutments at either side. A viaduct may be made from a series of arches. Truss bridge A truss bridge is a bridge composed of connected elements (typically straight) which may be stressed from tension, compression, or sometimes both in response to dynamic loads. Truss bridges are one of the oldest types of modern bridges. This type of bridge structure has a fairly simple design and is particularly cheap to construct owing to its efficient use of materials
- 29. 27 Oters structures Suspension bridge A suspension bridge is a type of bridge that has been made since ancient times as early as 100 AD. Simple suspension bridges, for use by pedestrians and livestock, are still constructed, based upon the ancient Inca rope bridge. Suspended from two high locations over a river or valley, simple suspension bridges follow a shallow downward arc and are not suited for modern roads and railroads. Advances in materials and design led to the development of the suspended-deck suspension bridge, a modern bridge capable of carrying vehicles and light rail. Instead of the deck following the downward arc of the main load-bearing cables (or chains), these cables are suspended between towers, and vertical suspender cables carry the weight of the deck below, upon which traffic crosses. This arrangement allows the deck to be level or to arc slightly upward for additional clearance.
- 30. 28 Modern Uses Modern Uses Today, most post and lintel construction has a third component, the wall, which adds additional support and hides the post and lintel design within the framework. It can still be seen in doorways and columns, in which the space between the vertical supports is open. Variations on post and lintel design can be found in bridges, complex archways and crossbeams, sometimes with cable support adding extra stability. Because post and lintel construction is so simple, it forms the base for the entrances to modern buildings that do not feature curves, which add stability.
- 31. 29 EXAMPLES The Parthenon, Greece St. Paul’s Cathedral, London Temple of Horus at Edfu, Egypt
- 32. 30 EXAMPLES The Parthenon, Greece St. Paul’s Cathedral, London Temple of Horus at Edfu, Egypt
- 33. 31 EXAMPLES Stonehenge, England. Temple of Karnak, Egypt. Glass House, Philip Johnson, Connecticut.
- 34. 32 Conclusion Form prehistoric times, the post and lintel System has been used for all kinds of structures. Since the Roman and Egiptian temples to the evolution of frames and archs, the post and lintel system has remained as the basic idea. Even now modern buildings use a basic post And lintel system idea. The engineers had combined these two elements to create a mushroom columns. This is column that has a slab at the end making it a column with support fuction it can become the ceiling of a structure.