Q.: Do you know of any equipment that uses vibration or ultrasonic waves to pulverize concrete? We have a bridge demolition project in Rock Island, Ill., that requires removing existing concrete-filled grating from the structure. Conventional means of removal is impractical due to a tight schedule, so we need to come up with something that will pulverize the concrete quickly. Any help would be appreciated.

A.: We are not aware of an ultrasonic device that can demolish concrete, although we've been told that such a device was being developed and was demonstrated at World of Concrete several years ago. Perhaps the best method for your application would be the use of hydrodemolition. This demolition process is frequently used on bridges and can remove as much as 4 inches of concrete in one pass without doing damage to steel reinforcement or steel grates.