The precast, prestressed and tilt-up systems are all installed with nearly identical practices.

1. The bottom layer of concrete is placed in the forms. This begins once the forms have been secured the surfaces cleaned and treated with a bond release agent and reinforcing has been placed. Reinforcing for the thinner (outer, lower) is typically 6x6 – W2.9xW 2.9, or as specified by the engineer of record.
   
   Note: The next three steps (steps 2, 3, and 4) are critical.
   
2. The pre-drilled insulation is then placed over the fresh concrete. This should be done immediately after the bottom layer has been consolidated and leveled to thickness, but in any event, within 15-20 minutes after placement of the concrete to ensure the mix is still plastic.
   
3. The fiber composite connectors should immediately be inserted through the pre-drilled holes.
   
4. The concrete around the connectors should then be consolidated. Walking on the insulation near each row of connectors and applying foot pressure on each side of the connector can do this effectively. This will cause the still fluid concrete to flow into the notch in the bottom side of the connector. Additional consolidation can be achieved by vibration of the bed in precast/prestressed plants. Also, Composite Technologies Corporation provides a connector vibrating device for use where insulation thickness exceeds 100mm (4”).
   
   Note: Steps 5 and 6 can proceed immediately. If steps 5 and 6 can’t be executed immediately, they must be performed after the concrete has set.
   
5. The reinforcement and hardware for the second concrete wythe can be placed.
   
6. The top wythe of concrete is then placed.

Contact CTC for installation guides for specific applications.

You must have concrete consolidation around the notch for the connector to develop its strength.

Exerting foot pressure on each side of the connectors is called “walking” the connectors (THERMOMASS Shuffle). It causes the unhardened concrete to flow around the notches in the connector. Good consolidation can be achieved by placing the insulation, inserting connectors and “walking” the insulation immediately after pouring a panel (within 20 minutes).

Note: Setting time varies as a function of many factors, including (but not limited to): mix design, concrete temperature, ambient temperature and mix time. The installer must ensure that the concrete has not reached initial set before connectors are installed.

A new row of holes can be drilled into the insulation by drilling holes with a 7/16” diameter drill bit. The new row of holes should be no closer than 100mm (4”) to the edge of the insulation.

Remove the connector and reinsert it at an angle to bypass the obstruction.