The document explains Bar Bending Schedule (BBS), which details the reinforcement calculations for construction structures, including cutting lengths and types of bends. It discusses the differences between actual length and cutting length for stirrups, emphasizing the importance of accurate measurements for effective reinforcement. Additionally, it illustrates how stirrups function within RCC structures and provides formulas for calculating lengths and deductions related to bending angles.

2.  WHAT IS BBS?
 Bar Bending Schedule, commonly referred to as “BBS”.
 Bar bending schedule provides the reinforcement calculation for a Reinforcement
Drawing of a Structure.
 It provides details of reinforcement cutting length, type of bends and bend length.
 WHAT IS CUTTING LENGTH?
 WHEN IT COMES TO THE LENGTH OF A STIRRUP BAR
THERE ARE TWO TYPES OF LENGTH
1) ACTUAL LENGTH
2) CUTTING LENGTH
450
MM
550
MM

3. CUTTING LENGTH IS ALWAYS SMALLER THAN ACTUAL LENGTH.
 WHEN YOU MAKE STIRRUPS WE CUT BARS BASED ON CUTTING LENGTH,OTHERWISE YOU CAN
NOT GET REQUIRED SIZE ,BCOZ OF BENDING BAR LENGTH INCREASES(STRETCHING IN BENDING
AREA)
 IF WE CUT BY ACTUAL SIZE,IT IS MORE LENGTH ACTUALLY WE NEED.

4.  WHAT IS STIRRUP?
 A STIRRUP IS A CLOSED LOOP OF REINFORCEMENT BAR THAT IS USED TO HOLD THE MAIN
REINFORCEMENT BARS TOGETHER IN AN RCC STRUCTURE.
 IN A COLUMN, THE STIRRUPS(TIES) PROVIDE THE LATERAL SUPPORT TO THE MAIN BARS
AGAINST BUCKLING.
 WHEN USED IN BEAMS, A STIRRUP IS TERMED AS SHEAR OR TRANSVERSE REINFORCEMENT
SINCE IT WITHSTANDS THE SHEAR FORCE.
(PUSHING ONE PART OF A BODY IN ONE SPECIFIC DIRECTION, AND ANOTHER PART OF THE BODY
IN THE OPPOSITE DIRECTION)

5.  BEND DEDUCTION
BEND ANGLE(IN DEGREE) DEDUCTION
45 1D
90 2D
135 3D
180 4D

6.  EXAMPLE
LONG SIDE OF BEAM=550MM
SHORT SIDE OF BEAM=450MM
CLEAR COVER=40MM
SO LONG SIDE OF STIRRUP=LONG SIDE OF BEAM-(2*CLEAR COVER)=550-(2*40)=470MM
SO SHORT SIDE OF STIRRUP=SHORT SIDE OF BEAM-(2*CLEAR COVER)=450-(2*40)=370MM
HOOK LENGTH=9D OR NOT LESS THAN 75MM=9*10=90mm

7. Actual length of stirrup is
=(2*long side)+(2*short side)+(2*hook length)
=(2*470)+(2*370)+(2*90)
=1870mm
CUTTING LENGTH OF STIRRUP
=[ACTUAL LENGTH OF STIRUP]-[BEND DEDUCTION]
=[(2*long side of stirrup)+(2*short side of stirrup)+(2*hook length)]-[(3*900 bend)-(2*1350 bend)]
=[1870 - 3*2D - 2*3D]=[1870 - 3*2*10 - 2*3*10]
=[1870-120]
=1750MM