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What is Frame Structure?
Framing is the process of mixing building materials to form the framework of a building. As a result, a framed structure uses beams, columns, and a slab to withstand gravity and other lateral loads. As a rule, these structures are employed to counteract the pressures and moments that emerge from the loading.
Characteristics of a Frame Structure:
Types of Frame Structure:
A. Based on the connection between the elements of a frame structure:
1. Rigid Frame Structure:
Beams and columns are examples of the linear elements that make up a rigid frame system, also known as a moment frame system. Rigidity is the inability to bend or flex. It is commonly found in reinforced concrete and steel structures. Static indeterminacy is a hallmark of rigid frames, distinguished by the absence of pinned joints between individual frame members.
A rigid frame does not bend under the weight of its beams and columns, making it resistant to vertical and lateral stresses. Beams and columns with rigid connections give the rigid frame its stiffness. The joints need to be sufficiently strong and rigid with little distortion.
Solving for internal forces and moments and support reactions can be done with structural analysis techniques such as the portal method (approximate), the method of virtual work, Castigliano’s theorem, the force method, the slope-displacement method, the stiffness method, and the matrix analysis.
Fig1: Rigid Frame Structure
A rigid frame structure can be divided into two categories:
i) Fix-Ended Rigid Frame Structure:
The conditions at the ends are usually set in this rigid frame system.
Fig2: Fix-Ended Rigid Frame Structure
ii) Pin-Ended Rigid Frame Structure:
Fig3: Pin-Ended Rigid Frame Structure
This rigid frame is held together by pins and is no longer a rigid frame if the pins are removed.
2. Braced Frame Structure:
Fig4: Braced Frame Structure
Bracing is typically installed between beams and columns in this frame system to strengthen the system’s resistance to lateral forces and sideways forces. Placing the diagonal elements between the beams and columns is a common bracing method. This skeleton design is more able to withstand earthquake and wind pressures. Compared to rigid frame systems, this one is superior.
A braced frame structure can be divided into two categories:
i) Portal Frames:
Fig5: Portal Frame Structure
Most portal frames are designed to resemble doors. In the commercial and industrial sectors, this frame system is widely used.
ii) Gabled Frames:
Fig6: Gable Frame Structure
Most of the time, the peak is at the top. This type of frame is used where it might rain or snow a lot.
B. Based on the materials used for the frame structure:
i) Steel Framed Structures:
Fig7: Steel Frame Structure
A steel framework is used to carry the weight of these structures. Steel sections are used for these structures’ columns, beams, and girders. Bracing should be sufficient for these structures to withstand wind and seismic effects. Lightweight and fireproof materials are typically chosen for these structures’ interior and external walls. Steel-framed structures are, therefore, analogous to reinforced concrete structures (RCC).
Steel can support significantly more weight in the same area than any masonry can. It allows for greater column-free areas by reducing the columns required for beam support at regular intervals.
ii) Wooden Frame Structure:
The wood frame structure is one of the most popular methods for constructing homes, businesses, and factories. Wooden frames are highly cost-effective to construct and provide a high level of comfort to the inhabitants by withstanding extreme climatic variations. Moreover, wood frames are carbon-neutral and help reduce emissions of greenhouse gases.
Fig8: Wooden Frame Structure
When working with wood, there are no limits to the architectural possibilities that can be explored. Buildings made of wood can serve their intended purposes if they are constructed utilizing good building techniques and methods. For instance, the lightweight nature of wood frames reduces the need for expensive cranes and other heavy machinery during the erection process, helping to keep construction costs down.
iii) RCC Frame Structure:
Fig9: RCC Frame Structure
An RCC structure has a grid of beams and girders connected at the floor and roof levels to create a series of frames. Within these frameworks, walls are built. All structural elements—the slab, the beams, the girders, and the columns—are constructed as one solid piece and meet at a stiff, unified junction. So, in a framed structure, the beams and girders take the weight of the floors, roofs, and walls and transfer it to the columns, which in turn transfer it to the foundations.
All RCC frames are built in a single, seamless piece to provide complete continuity between the columns, beams, and slabs (of floors and roofing). Buildings can be constructed more cheaply and safely with continuous construction thanks to decreased deflections and bending moments in the members.
Advantages of Frame Structure:
Disadvantages of Frame Structure:
A Frame structure uses beams, columns, and a slab to withstand lateral and gravitational loads. Typically, such structures are employed to counteract the resulting huge moments due to the imposed loading. Materials like rebar-strengthened concrete, steel, and wood are all good alternatives for constructing various frame structures.
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3. “Structural Components of Framed Construction | Bartleby.” Structural Components of Framed Construction | Bartleby, www.bartleby.com/subject/engineering/civil-engineering/concepts/structural-components-of-framed. Accessed 25 Oct. 2022.
4. “What Is a Frame Structure Building: Types and Advantages.” Real Estate Forum by NoBroker.com, 6 June 2022, www.nobroker.in/forum/what-is-frame-structure-building.
5. Struccore. “Types, Advantage and Disadvantages of Frame Structures | Struccore.” Struccore, 20 July 2016, struccore.com/2016/07/20/what-are-the-types-of-frame-structures.
6. “Different Types of Frame Structures – US Framing.” US Framing, 10 Dec. 2021, usframing.com/2021/12/10/different-types-of-frame-structures.
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