Q.: We must replace some large areas of highway pavements that contain large, irregular cracks that open and close, some of which intersect. If we remove the old concrete how can we be sure the new concrete won't settle independently or tilt to form faulted joints?
A.: Saw out large areas to eliminate cracks. Use a diamond core drill to make horizontal holes in the adjacent concrete and insert load transfer dowels across all the new construction joints. These should be cemented in place with a polymer concrete or other proven patching compound. Place concrete for the new slab, consolidate it by vibration, finish it to a texture like that of the surrounding concrete, and cure.