18. Wall rebar arrangement

1) Sequence of rebar arrangement① The worker is not allowed to change the rules and instructions of reinforcement

without permission. All the reinforcement should be in accordance with drawings

and specifications. Especially in retaining walls, if the retaining wall, which needs

double reinforcement, is placed in the sequence of the first main bar, assist bar, the

second main bar and then another assist bar, it might be an easy way but wrong

one. All the placement should be in the specified sequence.

② Placement sequence of wall suggested below

③ Place the stirrup closing bar densely and keep the thickness exactly. Especially in

the reinforcement of water tank, fabricate the reinforcement as specifically

suggested. And place the reinforcement at a time. In case the tank is big, the

reinforcement should be in zigzag and in the top span tying wire should be wound

at least one time before tying. If not, main bar would swing and would not

maintain the required shape. Simple cut bar reinforcement or hooking in the bar is

also a wrong reinforcement.

main barwidth fixing bar sub bar

reinforcement bar

width fixing bar

2) Principle of assembly and rebar arrangement binding

Assist bars might deflect when concrete is cast-in or due to loose bindings.

To avoid this undesirable deflection, width-fixing bar, which is similar to stirrup in

shape is fabricated to place in assist bars.

① Begin the placement of assist bars from 100mm above the floor place the stirrup

② Stirrup(closing bar) at every third step

※※ Caution in reinforcement of retaining wall

When numbers of bars are placed in the retaining wall, the worker should be

considerate.

If the tie between main bars and assist bars is loosened, the reinforcement would

lean toward.

Make sure that tying of main bars and fixing bars always go together in turn.

corner

saddle tie with twist

it should be tied with 1,2 timeswound depending on @ distance tying to maintain distance of upper part

3) Crosspoint main bar and horizontal rebar arrangement

<Single arrangement>

<Single and double arrangement>

<Double arrangement>

<Straight wall>

wall horizontal rebarU bar

U bar

U barwall vertical rebar

wall horizontal rebar

wall horizontal rebar

4) Details of wall on top floor

※ The end of wall vertical rebar on top floor should obtains unification by fixing

correctly on slab and processed to get 90°standard hook.

※ The upper part rebar of slab to contact outer wall should be fixing splice or making

tension folding splice and wall outer vertical rebar.

<Top floor outer wall> <Top floor inner wall>

90°standard hookroof floor slab

slab upper part bar

slab lower part bar

tensio

n sp

lice

over 150

wall vertical barwall horizontal bar

wall

roof floor slab

5) Tying position of revetment(retaining wall)As a rule, bar splice in pillars and beams is not allowed, and if horizontal bar is better

to be anchored in the pillar of every span.

※When the inserting bars as arranged straight bar are inserted at the underground beam

※ As shown above left, there is a possibility for stirrup vertical bar to be protruded

by the lack of cover thickness of fixing part.

It is recommended to adjust to fix the bar into the stirrup.

<resistance wall> <underground retaining wall>

<stirrup closing bar>

fixed length no problem if fixedlength will be obtained

tensionsplice

tensionsplice

pillar pillar horizontal bar vertical bar

good position to tie

B class tension splice

inside

inside

outside

outside

outs

ide

insi

de

foundation beam

beam

6) Indication of revetment(retaining wall)

arrange to 300mm distance of vertical High Density 16mm rebar

arrange to 200mm distance of vertical High Density 19mm rebar

arrange to 200mm distance of horizontal Density 16mm rebar

arrange to 200mm distance of horizontal Density 19mm rebar

<Symbol on wall >RW(Retaining Wall) = Underground wall(wall to resist against ground pressure)

Wall = Wall

THK = Thickness of wall

V = Vertical rebar

H = Horizontal rebar

T = Width Tie bar

H = Hunch, it is classify easily per type against tie hoop