Table of Contents
- 1 Where should we provide lapping in column?
- 2 Where do we provide overlapping In columns?
- 3 What is Zone-A and Zone-B in column?
- 4 What is lapping zone in beams?
- 5 Where is tension zone in beam?
- 6 What is the minimum overlapping distance?
- 7 How many zones are in a column?
- 8 What is tension zone and compression zone?
Where should we provide lapping in column?
Lapping should be arranged at the midpoint of the column. Lapping of bars should be arranged alternatively. Lateral ties should be placed narrowly in lapping zone.
Where do we provide overlapping In columns?
4) lap length should be provided in centre of column not in upper L/4 and lower L/4 structure length of beam. Because of maximum tension present in upper and lower part of column reinforcement.
Where do beams overlap?
The formula for overlapping in slab is given as 50d. Here, d denotes the diameter of bar. So, if the diameter of the slab is 8mm then total distance = 50 x 8 = 400 mm. The overlapping in tensile zone in column & beam = 40d (d = diameter of bar).
What is Zone-A and Zone-B in column?
As shown in Figure-2, due to the action of load, the column is subjected to a maximum moment at the ends and zero moment at the center. Hence, the top and bottom portion of the column subjected to maximum moment is categorized as Zone-A, and the portion at which the moment is reducing to zero is categorized as Zone-B.
What is lapping zone in beams?
Lap length may also be provided when the diameter of the reinforcement bar has to be changed along the length particularly during the reinforcement of columns. Such a process of overlapping the reinforcement bars side by side so as to obtain the desired design length is known as lapping.
What is Lap zone in column?
Lapping zone : The top and bottom portion of the column, i.e. zone-A ( L/4 length ) should be avoided as there will be a maximum moment in this zone due to lateral forces acting on the column.
Where is tension zone in beam?
the part of concave face of beam which lies upward to the neutral axis and has to elongate compared to neutral axis therefore is called as tension zone.
What is the minimum overlapping distance?
Normally, lapping position is at where near the minimum shear force is acting. Normally lap length is 50D meaning 50 times the bar diameter if both bars are of same diameter. When lapping two bars of different diameters, the lap length is considered as 50 times the smaller diameter.
How much is lapping for a column?
How Many Laps Is a Column? As per IS code 456, 30d lap length is provided in tension and minimum 24 d in compresson in column, beam and slab. But in general, 45d lap length are used for column and 60d are used for beam and RCC slab.
How many zones are in a column?
As per Indian standard codes, the columns are divided into three zones as shown in Figure-2 below. The zones are formed by considering the moment diagram of the column under lateral load.
What is tension zone and compression zone?
If load is acting towards the top, the compression zone will occur in the lower portion and tension zone will occur at the upper portion. The region above the neutral axis is termed as compression zone, while the region below the neutral axis is termed as tension zone.