Symbols and Abbreviations for Structural Drawing as per IS SP:34 1987
Symbol’s relating to Cross-Sectional Shape and Size of Reinforcement:-
φ plain round bar or diameter of the plain round bar,
□ plain, square bar or side of the plain square bar; and
# deformed bar (including square twisted bar) or nominal size (equivalent diameter or side) of the deformed bar
Symbols relating to the Shape of the Bar along with its Length
Alt
Alternate bar
Bt
Bent bar
B
Bottom bar
min
Minimum
max
Maximum
St
Straight bar
stp
Stirrup
SP
Spiral
Ct
Column tie
T
Top bar
Symbols Relating to Position and Direction
EW
Each way
@
Spacing centre-to-centre
↔
Limit of the area covered by bars
′―‚
The direction in which bars extend
Symbols Relating to Various Structural
Bm or B
Beams
Col
Column(s)
Fg
Footing(s)
GR
Girders
JT
Joints(s)
LL
Lintel(s)
LB
Lintel beam(s)
Sb or S
Slab(s)
WL
Longitudinal wall
Wx
Cross wall
CL
Centre line
The symbols, abbreviations and notes shall be used in a manner that will not create any ambiguity. A few examples for representing diameter, spacing, number of bars, etc. illustrated below:
# 20 @ 200 means 20 mm diameter deformed bars spaced at 200 mm centre-to-centre
20-#12 means 20 numbers of 12 mm diameter deformed bars
Φ 32-St-12 EW means 12 numbers of 32 mm diameter plain round straight bars in each direction