What Is Precast Concrete Column?
What Is Precast Concrete Column?
Precast concrete columns are a type of reinforced concrete column that is created by casting and curing the concrete on the ground before it is lifted into place. These columns are able to withstand shear, axial force, and bending moments, similar to in-situ columns.
However, it is important to pay close attention to the connection details when using precast concrete columns. The design process for these columns involves ensuring that the size, reinforcement, and connections are sufficient to withstand the external loads, second-order effects, and the process of lifting them into place.
Precast concrete columns are generally used in situations where they can be installed quickly and easily while maintaining structural stability and strength. The most common use for precast concrete columns is above ground parking garages as they are able to efficiently store vehicles in a safe manner.
Precast concrete columns can also be used for other types of buildings such as apartment buildings, hotels and office buildings.
Precast concrete columns are usually formed from prefabricated panels that can be transported across the site using machinery or through a crane which makes them very cost effective compared to traditional cast-in-place construction methods.
What Is The Purpose Of A Bearing Pad On A Precast Concrete Column?
Bearing pads are used in precast concrete connections to evenly distribute contact stresses and allow for movement between precast concrete elements, helping to prevent cracking at the connection points. These pads are typically placed between two precast concrete elements in order to provide support and facilitate movement as needed.
By distributing the contact stresses and allowing for some movement, bearing pads can help to prevent cracking and other types of damage at the connection points.
Bearing pads are commonly used in precast concrete parking garages to provide a buffer between different concrete members, similar to how cartilage functions between bones at joints. They are designed to last for the entire lifespan of the structure, but may need to be replaced if they become damaged or worn out.
These pads are typically placed under the ends of double-tee beams, as well as other beams and panels, to allow for expansion, contraction, and rotation at the bearing area while also preventing spalling and cracking of the supporting concrete.
They also help to absorb or transfer movement, noise, and vibration caused by traffic in the garage. It is important to properly design and install bearing pads, as they are expected to be permanent components with a lifespan equal to that of the structure.
However, in some cases, the actual service life of the pads may be shorter than their design life, requiring replacement before the end of the structure’s lifespan.
What Is The Purpose Of A Corbel In A Precast Concrete Column?
A corbel, also known as a bracket, is a reinforced concrete member that serves as a short cantilever used to support a reinforced concrete beam. It is a structural element that is used to support pre-cast structural systems, such as pre-cast beams and pre-stressed beams.
Corbels are typically designed to withstand significant loads and forces, and are an important part of the overall structural integrity of a building or other structure.
How Do You Provide A Connection Between Precast Beam And Column?
There are several ways to provide a connection between a precast beam and column in a building or other structure. Some common methods include:
- Shear keys: These are concrete elements that are embedded in the beam and column and are used to transfer shear forces between the two elements.
- Dowels: These are steel rods that are embedded in the beam and column and used to transfer horizontal loads between the two elements.
- Anchor bolts: These are bolts that are embedded in the column and used to anchor the beam to the column.
- Precast beam pockets: These are openings or recesses in the column that are used to hold the ends of the precast beam in place.
- Beam-to-column connections: These are specialized connections that are designed to transfer loads between the beam and column and can include elements such as shear plates, splice plates, and beam clamps.
It is important to carefully design and install the connections between precast beams and columns in order to ensure the overall structural integrity of the building or structure.