Concrete/masonry construction: Patching/replacing concrete spalled/broken off reinforcing steel on exterior reinforced concrete column. Here the concrete mason has just filled trowel with mortar from mortar board in his left hand and he is trowelling the mortar onto column. The repair process is the following: Cracked concrete is chiseled off (not shown in photos) down to sound concrete. Water is sprayed on dry sound concrete. Special bonding grout/paste is brushed on moist sound concrete, and mortar is troweled onto steel to produce new, structurally sound column. Ann Arbor, Michigan May 2006.

Concrete/masonry construction: Patching/replacing concrete spalled/broken off reinforcing steel on exterior reinforced concrete column. Here the concrete mason has just filled trowel with mortar from mortar board in his left hand and he is trowelling the mortar onto column. The repair process is the following: Cracked concrete is chiseled off (not shown in photos) down to sound concrete. Water is sprayed on dry sound concrete. Special bonding grout/paste is brushed on moist sound concrete, and mortar is troweled onto steel to produce new, structurally sound column. Ann Arbor, Michigan May 2006.