bar bending schedule of beam bent up bar

A bar bending schedule (BBS) is a crucial document used in construction projects, especially in reinforced concrete structures. It provides detailed information about the reinforcement steel bars that are essential for the stability and integrity of a building.

Beams

In modern building construction, Reinforced Concrete (RCC) beams stand as pivotal components. Their significance lies in upholding the structural integrity of a building. This comprehensive exploration of RCC beams will delve into their definition, diverse types, the intricacies of their construction, the merits they offer, and the critical design considerations.

RCC Beams and Their Purpose

RCC beams represent horizontal structural elements crafted from reinforced concrete, an amalgamation of concrete and steel reinforcement bars (rebar). This fusion with steel reinforcement significantly elevates the concrete’s strength and ductility, endowing it with the ability to withstand formidable loads and combat bending forces.

Types of Beams

Simply Supported Beams : These are the most prevalent beams, finding support at both extremities. They are frequently deployed for spanning openings in walls and for buttressing floors and roofs.

Cantilever Beams : Anchored at one end, these beams extend horizontally, commonly integrated into structures like balconies and canopies.

Continuous Beams : Supported by more than two points, these beams enable extended spans and a more even distribution of loads.

T-beams : ‘T’-shaped cross-section, these beams are widely embraced in building construction.

Merits of Utilizing RCC Beams

Robustness and Endurance : RCC beams boast impressive compressive and tensile strength, rendering them proficient in withstanding substantial loads.

Design Adaptability : The malleability of reinforced concrete permits a diverse array of beam shapes and sizes, accommodating an array of architectural and structural requisites.

Fire Resilience : Concrete, by its very nature, is fire-resistant, furnishing an additional safety layer to the building.

Cost-Efficiency : Abundant raw materials and straightforward construction practices render RCC beams a financially judicious choice for building endeavors.

Longevity : When appropriately conceived and maintained, RCC beams deliver an extended service life, augmenting the overall durability of the edifice.

Critical Design Contemplations

Load Calculations : Engineers are tasked with conducting meticulous load assessments to ascertain the optimal size and reinforcement of the RCC beam, factoring in the expected loads it will bear.

Reinforcement Detailing : The arrangement and spacing of rebar within the beam necessitate meticulous consideration to ensure peak structural performance.

Crack Mitigation : Rigorous detailing and construction practices are imperative in minimizing concrete cracks, which could potentially compromise the beam’s integrity.

Bar bending schedule of rectangular beam

beam section

Given,

beam length = 3000mm

beam depth = 300mm

beam width = 250mm

clear cover = 30mm

spacing of stirrups = 300mm C/C

Ld(development length) = 50d, d=diameter of bar

bends

45°=d

90°=2d

135°=3d

crank length=0.42d

Calculation of bottom & top main bar

Bottom main bar

Cutting Length = beam length+(2*Ld)-(2*bends)

=3000+(2*50*12)-(2*2*12) = 4152mm

weight = ((d^2/162)*CL)/1000= ((12^2/162)*4152)/1000= 3.690Kg

Top main bar

cutting length = Length of beam+(2*Ld)-(2*90°bends)

=3000+(2*50*12)-(2*2*12) = 4152mm

weight = ((d^2/162)*CL)/1000= ((12^2/162)*4152)/1000= 3.690Kg

top & bottom main bar

Calculation of bent up bar & stirrups

Bent up bar

cutting length = L+(2*Ld)+(2*crank length)-(2*bends)-(4*45°bends)

=3000+(2*50*10)+(2*0.42*10)-(2*2*10)-(4*1*10) = 4128.4 ~ 4129mm

weight = ((d^2/162)*CL)/1000= ((10^2/162)*4129)/1000= 2.548Kg

Stirrups

No. of stirrups = (beam length/spacing)+1

=(3000/300)+1 = 11nos.

cutting length = ((2*beam depth)-(2*clear cover))+((2*beam width)-(2*clear cover))+(2*hook length)-(2*135°bend)-(3*90°bend)

= ((2*300)-(2*30))+((2*250)-(2*30))+(2*10*8)-(2*3*8)-(3*2*8) = 1044mm

weight = ((d^2/162)*CL)/1000= ((8^2/162)*1044)/1000= 0.4124Kg

bent up bar & stirrups

bar bending schedule report

Sl. No.DestriptionBar dia (mm)spacing (mm)CL (mm)No. of barsWeight (Kg)
1.Bottom main Bar12415227.38
2.Top main bar12415227.38
3.Bent up bar10412925.096
4.Stirrups83001044114.536

Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top