Lockable Dowels

Lockable Dowels for Temporary Movement Joints

Lockable Dowels are used at temporary movement joints in post-tensioned concrete frames. These dowels allow initial shrinkage of the concrete to take place and are then locked in position with a mechanical plate and a controlled amount of epoxy resin. The locked dowels continue to transfer shear, but prevent further movement taking place.

Advantages

The use of Lockable Dowels can save a significant amount of time and materials over other construction methods. Traditionally, concrete shrinkage has been accommodated by leaving gaps in the slab called ‘pour strips’ or ‘closure strips’. These strips are filled once movement has stabilized, however until they are filled the slabs must be propped, restricting site access and delaying site progress.

Lockable Dowels improve site access, minimize formwork requirements and accelerate the rate of construction. With a Lockable Dowel, there is less requirement for the slabs to be propped or a support corbel to be constructed, as shear load is transferred by the dowel. The time saved by early removal of slab props can be significant.

A Lockable Dowel also provides many advantages over the site-assembled arrangement of carbon steel reinforcing bar, galvanized or plastic ducting, vent tubes and a non-specific grout, which is sometimes used by contractors.

  • Eliminate pour strips
  • Reduce propping times
  • Reduce formwork
  • Improve site access
  • Faster, safer construction
  • Proven performance

Applications

Lockable Dowels can be used to replace pour strips at temporary movement joints in post-tensioned concrete frames. Standard systems are available for use at slab joints and retaining / core walls.

Slab-to-Slab
  • Proven performance
  • Minimal material usage
Slab-to-Wall
  • Improved site access
  • Reduced propping time

Products & Technical Data

Performance Data

Slab-to-Slab

ESDQ-L20

The dowel component is manufactured from 30mm diameter stainless steel; one end features two fixed overlapping anchor discs and the other has a series of grooves to accept the Locking Plate. The cylindrical sleeve which accepts the dowel component is contained within a box-section to allow lateral, longitudinal and some rotational movement. Epoxy resin is poured into the L-shaped void former. This product has a design capacity of up to 71kN.

ESDQ-L20 LOCKABLE DOWEL (SLAB-TO-SLAB)
Slab Thickness Design Strength Longitudinal Load Vertical Design Strength (kip) for Various Design Joint Widths in 4000 psi Concrete
in. kip 1/4″ 1/2″ 3/4″ 1″ 1 1/4″ 1 1/2″ 2″
6.3 10.0 2.7 2.7 2.7 2.7 2.7 2.7 2.7
6.5 10.0 3.4 3.4 3.4 3.4 3.4 3.4 3.4
7.0 14.6 5.1 5.1 5.1 5.1 5.1 5.1 5.1
7.5 14.6 5.6 5.6 5.6 5.6 5.6 5.6 5.6
8.0 18.0 9.0 9.0 9.0 9.0 9.0 9.0 9.0
8.6 22.5 12.0 12.0 12.0 12.0 12.0 12.0 10.8
9.0 22.5 13.0 13.0 13.0 12.8 12.2 11.8 10.8
10.0 22.5 14.0 14.0 14.0 14.0 13.6 13.0 12.4
11 & Above 22.5 15.7 15.7 14.9 14.2 13.6 13.0 12.5
Edge Distance & Spacings

Slab-to-Slab

HLDQ-L30

The HLDQ-L30 is a high load Lockable Dowel with a design capacity of up to 136kN.

HLDQ-L30 LOCKABLE DOWELS (SLAB-TO-SLAB)
Slab Thickness Design Strength Longitudinal Load Vertical Design Strength (kip) for Various Design Joint Widths in 4000 psi Concrete
in. kip 1/4″ 1/2″ 3/4″ 1″ 1 1/4″ 1 1/2″ 2″
9.50 & above 22.5 30.6 30.6 30.6 30.6 30.6 30.6 30.6
Edge Distance & Spacings

Slab-to-Wall

ESDQ-L20W

The dowel component is manufactured from 30mm diameter stainless steel, but is shorter than the ESDQ-L20 dowel. One end of the dowel is designed to fix into the stainless steel threaded anchor cast into the face of the concrete and the other end features a series of grooves to accept the Locking Plate. The sleeve component is the same as used in the ESDQ-L20.

ESDQ-L20W LOCKABLE DOWEL (SLAB-TO-WALL)
Slab Thickness Design Strength Longitudinal Load Vertical Design Strength (kip) for Various Design Joint Widths in 4000 psi Concrete
in. kip 1/4″ 1/2″ 3/4″ 1″ 1 1/4″ 1 1/2″ 2″
6.3 10.0 2.7 2.7 2.7 2.7 2.7 2.7 2.7
6.5 10.0 3.4 3.4 3.4 3.4 3.4 3.4 3.4
7.0 14.6 5.1 5.1 5.1 5.1 5.1 5.1 5.1
7.5 14.6 5.6 5.6 5.6 5.6 5.6 5.6 5.6
8.0 18.0 9.0 9.0 9.0 9.0 9.0 9.0 9.0
8.6 18.0 12.0 12.0 12.0 12.0 12.0 12.0 10.8
9.0 18.0 13.0 13.0 13.0 12.8 12.2 11.8 10.8
10.0 18.0 14.0 14.0 14.0 14.0 13.6 13.0 12.4
11 & Above 18.0 15.7 15.7 14.9 14.2 13.6 13.0 12.5
Edge Distance & Spacings

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