BPI GRIP TWIST

BAR-TO-BAR. Taper-Threaded Grip Twist® and/or Grip-Twist® Position Couplers

Mechanical splices shall be the tension-compression cold-swaged taper-threaded type, comprising male/female couplers, and/or positional couplers, which shall be assembled by rotating the reinforcing bar and/or position coupler stud.

 

BAR-TO-HEAD. Taper Threaded DoughNUTTM

Mechanical Reinforcing Bar Anchorages shall be the cold-swaged taper-threaded coupler type, which shall be assembled with 5As or 10As Heads (Specifiy Head Size).

 

BAR-TO STRUCTURAL STEEL. Grip-Twist® Structural Connectors and/or Grip-Twist Structural Position Connectors

Bar-to-structural steel connections shall be the cold-swaged taper-threaded weldable connector type with weld bevels inclined 30-degrees to the rebar axis, and comprising male couplers, and/or positional components, which shall be assembled to the welded connectors by rotating the reinforcing bar and/or positional coupler stud.

Dimensions and product references

Dimensions and references Dimensions and data

Applications

FIELD SPLICE OPTIONS FOR YOUR PROJECTS

TAPER THREADED GRIP TWIST
COLD SWAGED STEEL COUPLER WITH TAPER THREADED ENDS

• FOR STANDARD REINFORCING BARS- ACI 318 Chapter 21 Seismic Design and International Building Code. Develops specified tensile strength of black deformed bars ASTM A 706 or A 615. Exceeds TYPE 1 requirements.
• CALTRANS SERVICE and CALTRANS ULTIMATE -.Meets slip test 670 and capable of developing the actual ultimate strength of black deformed bars ASTM A 706.
• SEISMIC LOADING - Tested to withstand plastic strain excursions to 5 x rebar uield strain value and stress reversals in accordance with ICC Acceptance Criteria AC-133, ICC Report No. ESR-2299.
• NUCLEAR APPLICATIONS - Swaged splices exceeding a tensile strength of 90,00 psi (150% x specified yield, fy ) when used with ASTM A 615 Grade 60 bar.
• COMMERCIAL APPLICATIONS - In accordance with Building Code Requirements for Structural Concrete, ACI 318 Chapter 12, used in columns, beams, walls, mats, tanks, parking garages.
• DOT PROJECTS and COATED BARS - Exceeds 125% x fy and 135% x fy , Grade 60 when swaged directly over epoxy coated ASTM A 775 or galv. ASTM A 767 bars without coating removal or shielding.

 

TRANSITION GRIP-TWIST
TRANSITION COD-SWAGED STEEL COUPLER WITH TAPER THREADED ENDS

• APPILCATIONS - Anywhere a change of bar size is required, in accordance with Building Code Requirements fro Structural Concrete, ACI 318 Chapter 12, typically in columns, walls, parking garages.
• CONVENIENCE- Components are color coded to match appropriate swaging dies. Standard MALE couplers are used on smaller bar. Thread protection is included.
• VERSATILE - Connect any size bar to any other by this method; typically 1, 2, 3 or 4 bar size changes..
• TRANSITION-POSITIONS - Can be achieved using a standard TPA (see below) on the small side and unwinding the pre-assembled stud into the adjoining Transition Female Grip-Twist.
• TYPE 2 SPLICE- ACI 318 Chapter 21 Seismic Design and International Building Code. Develops specified tensile strength of the smaller bar ASTM A 706 or A 615. Exceeds Type 1 requirements.
• SEISMIC LOADING - Tested to withstand plastic strain excursions to 5 c rebar yield strain value and stress reversals in accordance with ICC Acceptance Criteria AC-133.

 

GRIP-TWIST POSITION COUPLER
COLD-SWAGED POSITION COUPLER WITH THREADED STUD

• APPLICATIONS - Where bars are bent and cannot be rotated to engage the threads, or when bar lengths are long and impractical to rotate.
• NO ROTATION OF BARS - Assembly is completed in the field by unwinding a pre-assembled stud from a ‘TPA' (Taper Position Assembly) into an adjoining standard Taper Threaded Female Grip-Twist.
• FOR STANDARD REINFORCING BARS - ASTM A 706, ASTM A 615, ASTM A 996 and equal black deformed bars - exceeds specified ultimate tensile strength of Grades 40, 50, 60 and 75.
• CONVENIENCE - each TPA includes a parallel threaded coupler sleeve and a pre-installed stud that projects from one end. Each stud has an externally rolled thread with an axial taper.
• COATED BARS and DOT PROJECTS - Exceeds 125% fy Grade 60 when swaged directly over epoxy coated ASTM A 775 bars or galvanized ASTM A 767 bars without removal or shielding.
• TYPE 1 AND TYPE 2 SPLICE- ACI 318 Chapter 21 Develops both 1.25 fy and the specified tensile strength of black deformed bars ASTM A 706 or A 615.

 

GRIP-TWIST FLANGED COUPLER
COLD SWAGED FLANGED COUPLER WITH TAPER THREADED ENDS

• FOR STANDARD REINFORCING BARS- ASTM A 706, ASTM A 615, ASTM A 996 and equal black deformed bars - capable of exceeding specified ultimate strength of Grades 40, 50, 60, and 75.
• CONVENIENCE - Flanged couplers have holes that permit nailing them to formwork. They can be fully embedded in concrete thereby relieving certain constructability problems and potential injuries.
• NO DRILLING HOLES THROUGH FORMS - No protruding rebar when concrete is poured. Continuity across construction joint is established when rebar with male coupler is engaged.
• DOWEL BAR SPLICE - Ideally suited for dowel bar replacement applications because fabricating shops can utilize their own bars at their own location, including drops.
• TYPE 1 and TYPE 2 SPLICE- ACI 318 Chapter 21 Develops both 1.25 fy and the specified tensile strength of black deformed bars STM A 706 or A 615.
• COATED BARS and DOT PROJECTS - Exceeds 125% fy Grade 60 when swaged directly over epoxy coated ASTM A 775 bars or galvanized ASTM A 767 bars without removal or shielding.

 

TAPER THREADED DOUGHNUTTM
COLD SWAGED HEADED ANCHORAGE WITH TAPER THREADS

• 5Ab HEAD- TDS series for transmitting bond force from the reinforcing bar to concrete by a combination of head bearing and development length.* A ‘standard' head size for most applications.
• 10 Ab HEAD - TDX series has larger area to transmit full force in bar by head bearing alone. Generally used in sections that may be required to withstand higher forces. CALTRANS APPROVED.
• SHOP or FIELD INSTALLATION - Attaches directly to standard MALE Taper Threaded Grip-Twist that is swaged to the reinforcing bar - no thread cutting required. Shop-installed or swaged in-situ.
• HIGH STRENGTH - Connections to bar exceed the specified field strength of the bar, fy, as required by ACI 318 section 12.6. Confirming in-air tensile tests develop 1.5 fy, or more, Gr. 60.
• REPLACES HOOKS- No special bend direction - alleviates congestion - for beam-columning joints, knee joints, pile caps, column roof slab connections; replaces stirrup bars used as confinement steel.
• KEY ADVANTAGES - Avoids lengthy hook extensions / complex stress patterns. No heat, welding or hot forging - no special chemistry or rebar grade requirements, no bending or cracking of rebars.
* Ab= area of reinforcement. Minimum recommended anchorage lenth = 12db where db = bar dia; ref: "headed Reinforcement A Viable Option" John W. Wallace.

 

STRUCTURAL CONNECTOR
COLD SWAGED TAPER THREADED WELDABLE CONNECTOR

• CONVENIENCE- Cold swage standard MALE couplers to black ASTM A 615 or epoxy coated ASTM A 775 Grade 60 or galvanized ASTM A 767 Grade 60. Assemblies have capacity to exceed 1.25 fy.
• NUCLEAR STRENGTH CAPACITY - ASME Section III, Division 2- minimum joint strength 75,000 psi with average tensile strength 90,000 psi (150% x specified yield) used with ASTM A 615 Grade 60.*
• APPLICATIONS - For attachment of rebars to liner plates, structural steel shapes, or for creating headed anchorage. Structural-Positions can be achieved by using a standard TPA instead of a Male.
• CERTIFIED LOW CARBON STEEL - Weldable component conforms to CC-2310( c) material requirements of ASME Section III, Division 2. Meets chemistry AISI Grade 1018 and ASTM A 36.
• BEVELED FOR WELDING- For full penetration, provided for greater strength, convenience and quality assurance. Suited to E7018 electrode.
• BETTER THAN DIRECT BUTT WELD - The outside diameter of the structural connector is larger than the reinforcing bar so the weld area is disposed over greater length. This means LESS weld stress.
*Welder qualification, weld procedure, integrity and strength are the responsibility of others. 

Features

Strength requirements for mechanical splices established in ACI 318 are significantly higher than those for lap splices. Taper Threaded Grip-Twist has been qualified by in-air tests and protocols like AC-133 to sustain inelastic reinforcing bar strain excursions such as those that might be brought about by overload due to seismic activity- whereas the use of rebar laps in seismic zones is generally disallowed. The use of #14 and #18 lap splices is prohibited on all projects.

If spalling of concrete cover occurs around a lap bar by fire, corrosion or by another mechanism, the effectiveness of the rebar lap is severely compromised because its performance is 100% dependent upon the concrete that surrounds it. Clearly GRIP-TWIST® mechanical splices supplant all classes of lap splice including A, B, and C.

Benefits

GOOD REASONS FOR TAPER THREADED GRIP-TWIST® ON YOUR PROJECT...

1. Saves time- pre-installed by cold swaging. INTERNAL STOPS FOR EASY POSITIONING
Minimal detailing-more design flexibility.

2. No special bar preparation- avoids roughing and thread cutting operation on rebars.
No chasers, oils or cutting fluids.

3. Self-location- quick assembly- eases bar placement. NO SPECIAL TORQUE. Position couplers for bent bars.

4. No chemistry restrictions- compatible with ASTM A 615, A 706 and equivalent bars.

5. Thread Protection- color coded plastic plugs and caps match the color of swaging dies.

6. High strength- TYPE 2 performance and true Structural continuity, with load transfer independent of concrete. ROAD EXTERNAL THREADS INHERENTLY HAVE HIGH FATIGUE STRENGTH.

7. Full rebar cross-sectional area- no undercutting of rebar or heat affected zones.

8. In-situ installation- although normally pre- Installed, components can be swaged to existing Bars, if needed; using BPI-Grip field presses.

MECHANICAL ANCHORAGE is quickly and Conveniently achieved using the GRIP-TWIST Taper Threaded DoughNUTTM. Congestion problems Brought about by hook bars are alleviated.

Grip-Twist is superior to rebar laps- because as a mechanical splice it does not rely on the surrounding concrete to transfer forces between bars

Function

GRIP-TWIST is a Swaged Splicing and anchorage system that incorporates the use of self-locating taper threaded ends on components for expeditious field assembly. Because parts are swaged to the bars and the threads are formed on the couplers instead of the reinforcing bars, there is no loss of cross-sectional area and the full ultimate design strength of the reinforcing system is maintained.

Reinforcing bar sizes No.3-18 (dia. 10-67mm) can be spliced & anchored by Grip-Twist®. Swaging in advance means important time and cost savings for your project. Under fabrication shop conditions, with suitable equipment, just one or two pressings per coupler-half are all that is needed to install parts onto most bar sizes. Bars of different sizes may be connected using Transition Grip-Twist®.

Works carried out
  • Torre Costanera Center. CHILE
  • Tunel AVE. Tramo Abdalajis. Malaga
Photo gallery
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  • Costanera Center BPI Abril 2008 021.jpg
  • Costanera Center BPI Abril 2008 020.jpg
Installation

In the field it is only necessary to rotate one of the two bars until the threads of male and female couplers are fully assembled...no specialized equipment or torque wrench is needed for this operation-only a simple pipe wrench may be needed to overcome bar weight in accordance with assembly instructions. For locations where rebars have a bend or offset and cannot be rotated, Grip-Twist® position Couplers may be used.

Installation images
Quality Control

-Instituto Americano del Hormigón, código de la Edificación AC1318
-Código de Seguridad nuclear estructural AC1349
-ASME SECCION III, División 2
-US Corps de Ingenieros
-Código de la Edificación de los Ángeles
-Certificados consejo de Nueva York

Video of the solution