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As vertical load-bearing elements, columns are primarily responsible for sustaining compressive axial loads. As the name implies, this structural component is responsible for transferring the building's weight to the ground.
Reinforced concrete structures feature one-piece beams, floors, and columns. Some of the column's cross sections may experience tension as a result of the bending action. To this day, compression members (columns) are so named because of the predominance of compressive forces in their behaviour.
The major longitudinal reinforcement of spiral columns is held in place by spirals. Fortresses made with spirals are like a spring. Spirals stand in for ties, and the primary bars are enclosed in a circular pattern.
If you need a column that is both strong and flexible, look no further than a spiral column. Because the spiral prevents the column bars from moving laterally in response to intense axial forces. Spirals stand in for ties, and the primary bars are arranged in a circular pattern. In areas prone to earthquakes, spiral columns are more common.
Spiral Columns typically take on a cylindrical shape and have a spiral bar wound continuously around their circumference. The reinforcement used in the spinal column is helical reinforcement, which is known as spiral reinforcement too. In order to reinforce in a transverse direction, spiral reinforcement is used.
Spiral columns prevent the concrete from spreading laterally because of the spiral's shape. Spiral columns are used where pliability is vital or when cost-effectively improved strength is required to support heavy loads.
Spiral columns have more give before they fail because the principal longitudinal reinforcement is held in place by spirals. The spiral columns exhibit significant yielding, distortion, and failure. Spiral columns alert you well in advance of a failure, giving you time to make repairs.
Spiral brick columns are one style of column. Spiral brick columns required expert craftsmanship. Aesthetic appeal is heightened by spiral brick columns. Gardens, verandah entrance columns, and other ornamental uses for spiral brick columns have increased in popularity in recent years. The column is made from four square bricks set in a spiral pattern.
Tied columns have longitudinal bars interconnected with thinner bars. These progressively narrower bars appear at regular intervals further up the row. The primary transverse bars are confined by steel ties in the column. In non-seismic areas, tied columns make up more than 95% of the total number of columns in buildings.
Regularly spaced ties, transverse bars of lower diameter than the reinforcing bars, create a tied column. Ties are mostly used to make sure that the longitudinal bars are vertical during construction. The column's buckling resistance also contributes. The concrete around a failing tied column is crushed and sheared in all directions.
The column suddenly gives way because the longitudinal steel bars clasp outward between the straps. When the steel reinforcement is of a certain type, a tied column is employed. In tied columns, the major longitudinal bars are held in place by steel ties. Common practice dictates that ties be placed at regular intervals proportional to the column's height.
Each corner tie should support the next corner and longitudinal bar laterally. The top layer should be 75 mm from the lowest straight Reinforcement if all beams are securely bracketed and when there is concrete restraint at the top of the column from all four sides.
Tie-reinforced compression members require: like a tied column, the straps must be half the tie spacing above the footing and below the slab's lowest horizontal steel reinforcement. Linked columns spread vertical and horizontal loads across stone walls.
In order to accomplish this, it performs the function of a shear resistor, preventing the longitudinal steel reinforcement bars from buckling and, as a result, contributing to the prevention of shear failure.
The core of the concrete is encased, which contributes to the material's increased ductility and malleability. Because it secures the spliced bars in place, it prevents them from moving around in their new position.
The effective length of the vertical segment is three times the actual length of the vertical element. To withstand compressive pressures with the fewest possible sideways projections, a column is the structural element of choice.
Loads are supported by columns, which can be slabs or beams or even foundations or footings. Struts, which are used in trusses and frames, are angled components that support compression. The pedestal is a vertical compression section with an efficacious length of fewer than three times that of the column. It has the shortest lateral dimension.
Since columns support axial loads, they are designed to be compressed. Snow, wind, and other horizontal forces can also cause the columns to bend. The columns can withstand both bending and axial loads.
More weight can be supported by linked concrete columns, however, spirally reinforced concrete columns have less load eccentricity and can sustain more weight. When the load eccentricity is low, the strength and adaptability of columns reinforced with spirals are superior to that of columns reinforced with ties in terms of both strength and adaptability.
In reinforced concrete columns, it is therefore recommended to use spiral reinforcement instead of connections whenever possible.
I hope the blog provides you with a sound understanding of Spiral and Tied Columns. Please feel free to like, share and comment.
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