CE-2106

DESIGN OF CONCRETE STRUCTURES-1 (SESSIONAL)

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REINFORCEMENT DETAILING OF RC

TIED COLUMN

PRESENTATION ON

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Authorized by

DR. MD. MOZAMMEL HOQUE MD. KOBIR HOSSAIN

ASSOCIATE PROFESSORDEPARTMENT OF CIVIL

ENGINEERINGDUET, GAZIPUR-1700

LECTURERDEPARTMENT OF CIVIL

ENGINEERINGDUET,GAZIPUR-1700

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Our Group Member’s Student ID :121037 121038 121039 121040 121041 121042 121043

Student ID :121044 121045 121046 121047 121048 121049 121050

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Why do detailing of RC member?

Use commonly available size of bars and spirals. For a single structural member the number of different sizes of bars shall be kept minimum. Schedule bundled bars, lapped splice of bundled bars shall be made by splicing one barIndicate proper cover-clear cover, nominal cover or effective cover to reinforcement.

Use commonly available size of bars and spirals. For a single structural member the number of different sizes of bars shall be kept minimum.

Prepare drawings properly & accurately.

Generally Columns are vertical compression members of a structural frame intended to support the load-carrying beams. They transmit loads from the upper floors to the

lower levels and then to the soil through the foundations.

A member which design consider as axial load is called column

Main steel is provided to resist compression load along with concrete

Usually columns carry bending moment as well, about one or both axes of the cross section, and the bending

action may produce tensile forces over a part of the cross section

The main reinforcement in columns is longitudinal, parallel to the direction of the

load

Column

Longitudinal bar

Tie bar

Longitudinal bar

Tie bar6

Shape of Column

Circle

Square

Rectangle

o Min. 4 bars in rectangular/square column and min. 6 bars in circular shape column

2.5

b

h

d ≥12’’

d ≥ 12’’

Size of Column

2.5

Circular & Square column dm at least 12” or 300 mmRectangular column h/b >2.5

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h/b

Longitudinal Bar

The size of main bar isn’t matter

Reinforcement Building

At least 10 mm dia

Tie bar

main bar φ ≥ 32 mm

12 mm dia

Tie bar

Whenever longitudinal bar φ ≥ 32mm

Reinforcement building :Tie bar φ≥10mm φ

Semi Reinforcement : Any φ bar

Tie bar

Reinforcement Building

At least 10 mm diaTie bar

Sami Reinforcement Building

Any dia Tie bar

Minimum reinforcement provided at least (1-8)% according to ACI code

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For non seismic zone or ordinary moment reisting frame(OMRF)

S1=16 dm (minimum dia)

S2=48 tie bar

Minimum dimension.

Minimum s be provide

Seismically active region (IMRF/SMRF)

450mm

H/6 (not less than 18”)

Minimum dimension.

L1

L2

Middle part tie spacing similar to the OMRF

Spacing half of the middle part

Tie bar spacing

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L1

L1

L2

L1

When concrete of column carry maximum of load

If axial load is lower than longitudinal or main bar In that case main bar can be provide 50 % of architectural area

Corner tie spacing

75 mm

Spacing of main bar s>6” so each bar needed to a corner Bend of hook doesn’t exceed 135° Spacing of corner bar minimum 75 mm10

Min. distance b/w individual bars

-Minimum the dia of larger bar

-5mm more nominal max. size of coarse aggregate

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Why need distance bar to bar? For giving space when lap splice provide. When main bar of beam pass across the beam. 1.5” covering maintain impossible.

Why tie bar use in column? Maintain the position of longitudinal reinforcement

To prevent their buckling which may cause splitting of concrete. Assist confining the concrete

Lap Region

Lap should not provide near to the maximum moment. Lapping should not provide 50% more than any particular position It’s better to provide lapping in position of middle zone of column. In lap region tie should be provided closely as end region of column tie spacing.

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Tie bar alignment

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If spacing between two bar >6” tie should be provide with each main bar.If ≤6” tie should be provide alternately each main bar.

Thanks to All

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Any Query ??

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