How to Prepare a Bar Bending Schedule (BBS): Step-by-Step, with Formulas
Cutting length, bend deductions, lap length and the d²/162 weight rule — with a full worked example for a 6 m beam.
Topic
Steel & Rebar
Bar bending schedules, cutting lengths, unit weights and lap length. The reinforcement maths that decides your steel order.
Unit Weight of Steel Bars: the d²/162 Formula, Explained
Where the 162 comes from, a full bar weight table, the US n²/24 equivalent, and why delivered steel weighs less.
Cutting Length Calculations for Reinforcement Bars
Worked examples of rebar cutting length for straight, L-shape, U-shape, stirrup and bent-up bars, deducting 2d for each 90° bend and 1d for each 45° bend.
Types of Lap Lengths in Reinforcement: A Comprehensive Guide
Straight, hook, welded, coupler and transverse laps, development length, adjustments for concrete grade, coating and seismic zones, with worked examples.
What Is Lap Length in Reinforcement: Essential Guide for Construction Professionals
What lap length is, tension and compression laps, the factors that affect it, general, ACI 318 and IS 456 formulas, and a worked example for a 20 mm bar.
Physical Properties of Rebar
Physical properties of rebar: thermal expansion matched to concrete, rust, elongation under load, yield, fatigue, bond, strength in fire and joining.
Types of Rebar
Seven types of rebar — carbon steel, stainless, galvanized, GFRP, epoxy-coated, welded wire fabric and expanded metal — and where each is used.
What Is Reinforcement or Rebar
Reinforcement gives concrete higher tensile strength. Why rebar is ribbed, its main types — carbon steel, stainless, fibre composite — and epoxy coating.
Chemical Composition of Reinforced Bar
How carbon, manganese, sulphur, phosphorus, copper, chromium and carbon equivalent affect rebar strength, ductility, weldability and corrosion resistance.
Coupler: Types and Benefits
What a rebar coupler is, why it replaces lap splicing — less steel, faster fixing, higher tensile strength — and the tapered thread and Bartec Plus types.
What Is a Cover Block? Sizes and Use of Cover Block
Why cover blocks keep rebar clear of the shuttering, the 20 to 70 mm sizes and cover for columns, beams and slabs, and concrete versus PVC types.