Material testing verifies that products meet specifications. Concrete testing includes slump (workability), air content, and cylinder tests for strength. Testing occurs at placement and after curing. Non-destructive testing allows in-place strength assessment. Rebar testing verifies yield strength and ductility. Rebar mechanical testing confirms specifications. Mill certs from manufacturers document properties. Steel testing verifies yield and tensile strength. Welds must meet tensile strength and ductility requirements. Ultrasonic testing identifies internal defects. Paint and coating testing verifies adhesion and durability. Accelerated weathering tests simulate years of exposure. Soil testing characterizes bearing capacity and settlement characteristics. Moisture-density tests verify compaction. Classification determines appropriate construction methods. Laboratory analysis guides engineering decisions. Acceptance testing before use of materials prevents construction with substandard materials. Rejection of non-conforming materials prevents failures.