ASTM D6760-16 PDF Download

The ASTM D6760-16 standard provides guidelines for assessing the homogeneity and integrity of concrete in deep foundation elements such as bored piles, drilled shafts, and concrete piles. The test method involves using ultrasonic probes that are lowered into parallel access ducts or a single access duct in the deep foundation element. The data collected from the probes are utilized to confirm the quality of the concrete or identify areas of poor quality. In cases where defects are detected, further investigations such as excavation or coring may be required to assess the extent of the issue.

The standard specifies certain limitations. For crosshole tests, it is recommended to use steel access ducts to prevent debonding, which could result in anomalies. The test mainly assesses the integrity of the concrete between the access ducts, typically within the reinforcement cage. In the case of single hole tests, plastic access tubes are used, and testing should be performed quickly to avoid debonding issues. However, unless a flaw is significant and located near the access duct, it may not be detected using this method.

The standard also emphasizes that the competence of the personnel performing the test and the suitability of the equipment and facilities used are crucial for obtaining reliable results. Compliance with the guidelines provided by Practice D3740, which evaluates these factors, is recommended but does not guarantee accurate outcomes. The standard concludes by stating that additional requirements and procedures may be stipulated by qualified engineers in the plans, specifications, or provisions of a particular test program.

In terms of the test method itself, it measures the propagation time and relative energy of an ultrasonic pulse between the access ducts or within a single tube installed in the deep foundation element. It is important to note that this standard does not cover similar techniques that use different excitation sources. The observed and calculated values must conform to the guidelines for significant digits and rounding established in Practice D6026. The application and interpretation of test results are beyond the scope of the standard. Lastly, it highlights that while the method can identify the presence of flaws, it does not provide information on the exact type of flaw.