What must be done during concreting to ensure the proper alignment, safety and other performance of formwork?
It should be continuously watched during concreting and afterward by one or more persons stationed close to the formwork but in positions that are protected. The form watchers should have a means of communicating with placing crews in case of emergency. They should watch telltale devices installed on the forms to check for camber, elevation or plumbness of the system. Necessary adjustments should be made promptly by tightening wedges or jacking, or by other suitable measures. Such adjustments must be made before the concrete begins to set. If the forms begin to bulge beyond tolerable limits the form watchers should notify the superintendent so that he can slow down or stop the work long enough to install more bracing or use other corrective measures. The form watchers should remain on duty until the concrete has been screeded and the telltale devices show that no more deflection is occurring. When there is an impending form failure, a gradually increasing deflection will often occur which serves as a warning.