Precast Concrete Forms

Application Suggestions

1. Metal forms transmit vibration far more effectively than wood forms.
2. Always stiffen up forms to avoid distortion and flutter and for best vibration transmittal to concrete.
3. Rest forms on wood beams or rubber mats to avoid vibration transmittal to floor and surrounding forms as well as for quiet operation and increased vibration amplitude and uniform compaction.
4. Vibration time depends on height and structure of form. Vibrators should be on until a flattened, glistening surface appears and no more air bubbles burst on the surface.
5. Concrete of proper consistency is not susceptible to over vibration and segregation. If segregation occurs, reduce slump, not vibration time.

Bridge Sections Cast On Site

THE CHALLENGE

The construction site is the bridge replacement on Interstate 95 in Connecticut over the Connecticut River in which the bridge sections are cast on site.

The major problem was the large amount of blemishes, imperfections and honeycombs throughout the finished product. The concrete is being pumped into steel forms where a matrix of reinforcement is placed. The mix has a 3" slump.

THE SOLUTION

Five SVRF-5500 High Frequency Vibrators were installed on each bridge section form which eliminated the honeycombs and imperfections. These vibrators were operated with 90 PSI air.