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This report provides methods for estimating the in-place strength of concrete in new and existing construction. These methods include: rebound number, penetration resistance, pullout, pull-off, ultrasonic pulse velocity, maturity, and cast-in-place cylinders. The principle, inherent limitations, and repeatability of each method are reviewed. Procedures are presented for developing the relationship needed to estimate compressive strength from in-place results. Factors to consider in planning in-place tests are discussed, and statistical techniques to interpret test results are presented. The use of in-place tests for acceptance of concrete is introduced. The Appendix A provides information on the number of strength levels that should be used to develop the strength relationship and explains a regression analysis procedure that accounts for error in both dependent and independent variables. Keywords: coefficient of variation; compressive strength; construction safety; in-place tests; nondestructive tests; sampling; statistical analysis.

This Code provides material, design, and detailing requirements for cast-in-place and precast reinforced concrete chimneys. It sets forth minimum loadings for design and contains methods for determining the concrete and reinforcement required to obtain the strength required by the loadings. The methods of analysis apply primarily to circular chimney walls, but guidance is included for applying the general principles to noncircular chimney walls. Keywords: across-wind load; construction requirements; earthquake load; flexural strength; load combinations; reinforced concrete; reinforced concrete chimneys; structural design; thermal load; vortex shedding; windload.

This Code prescribes testing programs and evaluation requirements for post-installed adhesive anchors intended for use in concrete under the design provisions of ACI CODE-318-25. Testing and assessment criteria are provided for various conditions of use, including seismic loading; sustained loading; aggressive environments; reduced and elevated temperatures; and for determining whether anchors are acceptable for use in uncracked concrete only, or acceptable for service both in cracked and uncracked concrete. Criteria are provided for establishing the characteristic bond strength, reductions for adverse conditions, and the anchor category and associated jobsite quality control requirements. Keywords: adhesive anchors; cracked concrete; fasteners; post-installed anchors; qualification procedures; uncracked concrete.

This Code prescribes testing programs and evaluation requirements for post-installed mechanical anchors intended for use in structural applications addressed by ACI CODE-318 and subjected to static or seismic loads in tension, shear, or combined tension and shear. Criteria are prescribed for determining whether anchors are acceptable for use in uncracked concrete only, or in cracked as well as uncracked concrete. Performance categories for anchors are established, as are the criteria for assigning anchors to each category. The anchor performance categories are used by ACI CODE-318 to assign capacity reduction factors and other design parameters. Keywords: anchors; cracked concrete; expansion anchors; fasteners; mechanical anchors; post-installed anchors; screw anchors; undercut anchors.

This Code prescribes testing programs and evaluation requirements for post-installed reinforcing bars intended for use in concrete under the straight-bar development and splice length design provisions of ACI CODE-318. Testing and assessment criteria are provided for various conditions of use, including seismic loading, sustained loading, aggressive environments, and reduced and elevated temperatures. Criteria are provided for establishing the required characteristic bond strength, reductions for adverse conditions, and associated job-site quality control requirements. Keywords: post-installed reinforcing bars; qualification procedures.