We are a shotcrete contractor in Gold Coast, Australia. We have noticed that in the United States, you use different types of tools for cutting the shotcrete. How do you maintain a plum wall with the shotcrete rods? When a project requires a smooth finish or steel trowel finish, what are the tools and processes that are typically used? Finally, for a structural wall, what is the typical psi (MPa) and size of aggregate used?

The face or surface of shotcrete walls as described are typically established with ground wires or screeds, which assist the person using the shotcrete rod in cutting the wall to the proper plane. The tools typically used to achieve a troweled surface are the shotcrete rod, wood floats, and steel trowels. Typically, shotcrete walls are a minimum of 4000 psi (27.6 MPa) 28-day compressive strength and the aggregate varies from sand only to a blend of sand and 0.375 to 0.5 in. (9.6 to 13 mm) aggregate. Consult our Shotcrete magazine archives for examples at www.shotcreteweb.wpengine.com.