Masonry/Tilt-Up Hybrid Construction

Masonry or Tilt-Up?, Concrete Construction November 2003, reports on a new system for combining unit masonry elements into tilt-up concrete construction. The system, licensed under the Chameleon Cast Wall System name, opens up new possibilities for facing concrete walls constructed using the tilt-up method.

For an explanation of the tilt-up concrete construction method, see page 537 in the textbook. Tilt-up's main advantage is its cost savings through the elimination of most of the usual formwork required for wall construction.

In this new hybrid system, concrete masonry facing units are first laid face down on the casting bed. These unit facers are specially-fabricated 2-inch thick concrete masonry units with keyed backs. Next sand is broomed into the joints between facers, to prevent the concrete that will be poured next from seeping through to the face of finished wall. Subsequent construction follows normal tilt-up procedures: first placement of reinforcing, then concrete placement, and after initial curing, raising of the cast wall section into position.

Masonry unit facers for this hybrid system can come in any of the various finishes, textures, and colors normally available with standard CMU, and can be laid up in any pattern or bond. Chameleon Cast Wall licenses the system to facer manufacturers. They also provide test data documenting the system's durability and structural performance, and provide construction crew training.