Unexpected interactions between otherwise acceptable ingredients in portland cement concrete are becoming increasingly common as cementitious systems become more and more complex and demands on the systems are more rigorous. Such incompatibilities are exhibited as early stiffening or excessive retardation, potential for uncontrolled early-age cracking, and unstable or unacceptable air void systems.

Based on the experimental work described in this volume, a protocol has been developed to allow product manufacturers, concrete producers, contractors and owners to monitor their materials and concrete systems. The protocol is phased to allow relatively simple field tests to provide early warnings of potential problems, and central laboratory tests to support and confirm the field work. Tests conducted before beginning construction allows users to plan for changes in materials and environment. By monitoring materials with relatively simple field tests during construction, the users can detect when significant changes have occurred, indicating potential construction problems.