Precast Assignment 2
Precast Assignment 2
Precast Assignment 2
Question 3
At the construction site, evaluate all major connections of the project and provide structural
detailing of:
I. Beam to column
II. Slab to beam
III. Column to foundation
Answer:
Connection in Precast Concrete construction shall perform two key functions which are first,
to ensure the final structural performance of building and second, to provide temporary
support during component erection. They are three type structural component that need a
connection which are beam to column, slab to beam and column to foundation.
All three type structural component above are conventional connections which is using
reinforcing bars connection that have been designed for this project. Reinforcement bar
connection system that is designed to allow for simple and fast continuity of steel
reinforcement across construction joints in concrete.
I. Beam to Column
Usual practice is to work out the reinforcement in column above and below the joint area and
provide reinforcement equal to greater out of the two throughout the joint. Length of column
for this purpose is taken as sum of half the length of upper storey and half the length of lower
storey. Once the reinforcements in beam and column are determined, the beam formwork is
placed around already installed column bars. Later, beam reinforcements are placed.
In this type of structure, multiple connection plates are used to transfer the force caused under
shearing action along with the moment created in bending. These plates are fixed along
column flanges through the welding process. The sides of the plate are fixed along the
column flanges, while the edges of the plates are fixed along the beam flanges through the
welding.
In order to prevent any kind of crippling or buckling phenomenon, multiple continuity plates
are fixed between the two beam flanges on each side of the beam web. Two horizontal
constraints connect the flanges of two continuous beams on both sides of the connections.
II. Slab to Beam
This type of slab is supported with beams and columns, with the load transferred to
those elements. A conventional slab is classified as either:
Next, a formed concrete wall, called a stem wall, is poured on top of the footing. The stem
wall typically isn't reinforced with steel because it's not subjected to the movement or
expansion of the soil underneath like the footing is.
After that, the under-slab plumbing gets added and then the interior area of the concrete floor,
commonly referred to as the slab, is poured. The concrete slab isn't physically attached to the
stem wall, so it's commonly known as a floating slab.
Figure 1 : Shows the pictures of connection between beam to column