23. Mechanical tying of Rebar

1) What is mechanical tying of rebar?It is essential construction method for large scale civil engineering construction such

as high-building, bridge, dam, etc and underground building anti-earthquake plan and

also special construction. It is a splice method for strong economic quality assurance if

folded tying method is impossible in case rebar arrangement with density and rebar

diameter is bigger and so by the increase of rebar strength & concrete strength. It is

applicable for deformed rebar to use rebar concrete building. In foreign countries, it

was verified from 1960 and it is using for Korean construction site from mid-1990.

2) Type of mechanical tying of rebar

3) Screw-type tying of rebarrebar warehouse-in → make rebar screw process drawing → start processing of screw type

→ deliver to construction site(3~10days from order date)

screw type

inflationtype

compressiontype

joint ribcut type

tapertype

others

mortarinjection type

gascompression

hydrauliccompression type

site tie type

joint fixed bodyadhesion type

joint rib compressedjack adhesion type

processtype

process type inflation type compression type joint rib cut type taper type

inflate of rebar processingpart largely by mold(example) rebar 25mm - M30case screw type

bury rebar joint rib bymold (example) rebar25mm - M25.5

processing screw after deletingrebar joint rib with fixed size(example) rebar 25mm - M26

screw processing withangle of rebar front end

prove the confidenceafter processing of lowcarbon steel bar(SD300)available for largeproduction

prove the confidence afterprocessing of low-midcarbon steel bar(SD300,400)available for largeproductionavailable for production onconstruction site

prove the confidence afterprocessing of low-mid-high carbon steelbar(SD300,400,500)available for large productionavailable for production onconstruction site

prove the confidenceafter processing of lowcarbon steel bar(SD300)available for productionon construction site

the inflation processing endmight has low confidence ifit is caused by processingvulcanization of mold incase high carbon steel barlow confidence afterbinding 2 rebarslow confidence in case ofbending

the compressionprocessing end might haslow confidence if it iscaused by processingvulcanization of mold incase high carbon steel barlow confidence in case ofbending

coupler size is 10%longer than inflation &compression type by thedeviation of size ofrebar joint & rib

low confidence ofomission & untying fortesting tension strengthand repeat test

case screw type case screw type cut screw typescrew processing

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4) Site connection-type tying of rebaroutbreak of splice → carry-in of parts(arrival to site within 12hours after ordering) →assembly & construction carry-out → inspection comparing other splice part

process type

classification joint fixed body adhesion type joint rib compressed jack adhesion typeprecision processing & molding per part of splicepart base on joint groove of rebar(no artificialprocessing of rebar)

precision processing & molding per part of splicepart base on nominal diameter of rebar(no artificialprocessing of rebar)

available to assemble without processing screw onrebar

available to assemble without processing screw onrebarease to bind regardless of rebar type(foreign &domestic rebar , deformed rebar , comb-patternrebar , X type)available for large production per rebar title

need pre-education for building assembleravailable for deformed rebar only in Korea and lowconfidence of binding in case disorder of toleranceof rebar joint rib and trademarkneed pre-education for building assembler

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inflation screw swage screw joint-rib screw taper screw

cut processing cut processing cut processing cut processing

pre-cut after mold inflation mold compression pre-cut processing angle processing

case screw case screw case screw cut screw

lock nut fixed pincompression jack

lock coupler

connection jack

fixed bodyrebar

length after bindingoute

r dia

met

er o

f cou

pler

double facedcoupler

5) Other tying of rebar

process type

classification mortar injection type gas compression type hydraulic compression type

splice part to perform platform onrebar joint & rib groove & insideof connection part

heat & compression splicemethod of both ends of rebar byusing oxygen & acetylene

splice method to adhere sleeve bypressing outside sleeve afterclosing rebar to soft sleeve

using to pre-cast(PC) spliceconstruction method

using in Japan mostly and provethe confidence of tensioncompression

using in europe partly

splice part is large and longexcessively and low confidenceper rebar typedifficulty of confidence proofof construction site carry-outproduct

big tolerance of constructionsite carry-out per condition oftemperaturedifficulty of confidence proofof construction site carry-outproducttroublesome of purchaseseparately of compressed rebarfor compression reinforcementto classify to producecompression bar & regular bar

difficulty of reinforcementbecause the possibility ofdisplacement of pressurestrength for 1pc & 100pcs andalso the movement of pressuretool

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