The American Society for Testing and Materials (ASTM), the Corp of Engineers and the American Concrete Institute (ACI), are key organizations responsible for establishing standards and specifications for nonshrink grout and concrete repair. The beneficial work of these organizations is important to industry. Reports, such as “Grouting between Foundations for the Support of Equipment and Machinery” (ACI 351.1R-99), provide an excellent overview for evaluating and selecting nonshrink grouts based on the different expansion mechanisms used by grout manufacturers. Because some of these expansion mechanisms have a significant effect on the successful use of grout products in the field, ACI 351.1R-99 is an important tool for owners, engineers, architects, specifiers and contractors.
However, the nature of some committees within industry organizations is to generate standards and practices around consensus. This is particularly evident with respect to nonshrink grout. Because of this, the term “nonshrink” is one that has often been used loosely and not clearly defined – certain “nonshrink” grouts available in the marketplace actually do exhibit shrinkage when tested by ASTM test methods. Because of this, engineers, architects, specifiers and owners must specify exact performance properties with respect to vertical height change characteristics of grouts, and contractors should understand the importance of the standards and specifications they are given. A successful grout job is the joint responsibility of the engineer, the contractor, and the manufacturer. The generic use of the term nonshrink in standards and specifications is insufficient. This handbook, in conjunction with ACI and ASTM standards, can guide the strengthening and use of product specifications to ensure proper selection, specification, and use of precision nonshrink grouts and concrete repair materials.