CIVILGYAN
CivilGyan
Test Series
← AutoCAD

Drafting Structural Details

Structural drawings in AutoCAD — types (foundation/column layout, framing plans, beam, column, slab, footing, staircase and retaining wall details, steel connections); conventions and scales; layers and lineweights for concrete outlines, reinforcement and annotations; drawing RCC members — beam longitudinal section and cross-sections, column sections and schedules, slab reinforcement plans, isolated footing details, staircase reinforcement; representation of bars (polylines, donuts), bar marks and labels, cover, laps, hooks and bends; schedules with TABLE — beam/column schedules and bar bending schedules; structural steel details — sections, bolts, welds and connections; general notes; checks — with worked command sequences.

Drafting Structural Details
CIVILGYAN TEST SERIES · civilgyantests.com — free study notes for civil engineering exams
📑 Contents (13 sections)

Last reviewed 16 Sept 2026 · 9 min read

Types of structural drawings

Drawing Content Typical scale
Centre line / column layout plan Grid, column positions and marks, orientation of columns 1 : 100
Foundation plan Footing sizes and marks, pedestals, plinth beams, excavation depths 1 : 100
Framing (beam) plans Beam marks and sizes, slab marks, openings, levels at each floor 1 : 100
Beam details Longitudinal elevations and cross-sections with reinforcement 1 : 20, 1 : 25, 1 : 50
Column details / schedule Sections, longitudinal bars, ties, lap locations per floor 1 : 20
Slab details Reinforcement plans (main and distribution bars, extra top bars), sections 1 : 50
Footing details Plan and section showing bottom mesh, column dowels, pedestal 1 : 20 / 1 : 25
Staircase details Waist slab reinforcement, landing beams 1 : 20
Retaining walls, water tanks Sections and elevations with reinforcement 1 : 20 / 1 : 50
Steel structures Member layouts, truss elevations, connection details, bolt/weld details 1 : 50 to 1 : 10
Bar bending schedules Tabulated bar shapes, sizes, numbers, lengths, weights —

Conventions and layers

Layer (example) Content Lineweight idea
S-GRID Grid lines (CENTER) Thin
S-CONC Concrete outlines (members cut or in elevation) Medium
S-CONC-HIDDEN Beams/members below slab or hidden edges Thin dashed
S-REBAR-MAIN Main reinforcement in elevation — thick lines Thick
S-REBAR-SEC Stirrups/ties/distribution bars Medium
S-REBAR-DOTS Bars in section — filled circles (DONUT) —
S-DIMS, S-TEXT, S-TAGS Dimensions, notes, bar marks/leaders Thin
S-HATCH Concrete hatch in sections (e.g. AR-CONC) or earth/PCC Very thin
S-TABLE Schedules Thin

Conventions:

  • Concrete outline thinner than reinforcement; reinforcement shown thicker so it stands out.
  • In cross-sections, bars appear as solid dots sized to scale (or symbolically enlarged); stirrups/ties as closed polylines with 135° hooks indicated.
  • Bars labelled with number–diameter–mark, e.g. 4-16Ø (a) or 3 T16, spacing 8Ø @ 150 c/c.
  • Covers noted in general notes and dimensioned where critical.
  • Members identified by marks (C1, B1, S1, F1) consistent with layout plans.

Drawing reinforcement objects

Element AutoCAD technique
Main bars in elevation PLINE with Width equal to plotted thickness × scale (or lineweight), including hooks/bends using arcs
Bars in section DONUT with inside diameter 0 and outside diameter = bar diameter (e.g. 16) at true size, or larger for clarity
Stirrups/ties Offset the concrete outline inward by cover + half bar diameter; FILLET corners with bend radius; add hook lines
Spacing of stirrups/slab bars ARRAY or MEASURE/DIVIDE with blocks, or a single representative bar with a spacing note and range arrow
Cranked bars PLINE with 45° segments (relative polar @d<45)
Labels MLEADER with bar mark text; attributes in a bar tag block

Example — RCC beam detail

Beam B1: 230 × 450 mm, clear span 4000 mm, supports 230 mm wide; clear cover 25 mm; bottom 3-16Ø, top 2-12Ø, stirrups 8Ø @ 100 c/c near supports (over 900 mm) and 150 c/c at mid-span.

Longitudinal section (1 : 25 on paper):

  1. Draw the beam outline: RECTANG 0,0 to @4460,450 (span + two bearings); supports as column/wall outlines.
  2. Offset outline by 25 + 8 + 8 = 41 mm (cover + stirrup + half main bar) from bottom to locate bottom bar centreline; top similarly for 12 mm bars.
  3. Draw bottom bars as a PLINE (thick) with end anchorage (bends into supports) and top bars with anchorages.
  4. Draw stirrups as vertical lines: first at 50 mm from support face; ARRAY at 100 mm over 900 mm near each support and at 150 mm in the middle zone; annotate spacing zones with dimension strings.
  5. Mark section lines X–X (near support) and Y–Y (mid-span).

Cross-sections (1 : 10 or 1 : 20):

  1. RECTANG 230 × 450.
  2. Stirrup: OFFSET rectangle inward by 25 (cover to stirrup outside) and by 33 (to stirrup centreline) → draw stirrup as PLINE with FILLET radius and 135° hooks.
  3. Bars: DONUT 0, 16 at bottom corners/middle (centre 25 + 8 + 8 = 41 mm from faces); DONUT 0, 12 at top corners (25 + 8 + 6 = 39 mm).
  4. Label with MLEADER: 3-16Ø, 2-12Ø, 8Ø @ 100/150 c/c.
  5. Dimension width, depth and cover.

Downloaded from civilgyantests.com · Not for resale. Verify every code clause and date against the official source.

This chapter is in the syllabus of

Open an exam to see where this chapter sits in its syllabus, and to practise it.

JKSSB Draftsman Civil