Core testing is a partially destructive test of concrete.

Core Testing:
Core testing involves extracting cylindrical samples, or cores, from the concrete structure. These cores are typically drilled using a diamond-tipped core drill. The extracted cores are then tested to determine various properties of the concrete, such as compressive strength, density, and durability.

Procedure:
The core testing procedure involves the following steps:
1. Selection of location: The locations for core extraction are typically chosen based on a sampling plan that considers factors such as the age, type, and condition of the concrete structure.
2. Core extraction: A core drill is used to extract cylindrical samples from the structure. The diameter and length of the core are specified based on the testing requirements.
3. Surface preparation: The ends of the extracted core are trimmed and prepared to ensure smooth and parallel surfaces for testing.
4. Testing: The cores are subjected to various tests, including compressive strength testing, to determine the quality and properties of the concrete.
5. Analysis: The test results are analyzed to evaluate the strength and other characteristics of the concrete.

Advantages:
Core testing offers several advantages in assessing the concrete quality:
- It provides direct information about the in-situ properties of the concrete.
- It allows the evaluation of the structural integrity and strength of the concrete.
- It can help in identifying the causes of concrete deterioration or failure.
- It provides valuable data for the assessment of existing structures and the design of new ones.

Limitations:
However, core testing also has some limitations:
- It is a partially destructive test since it involves drilling and extracting cores from the structure, which can cause minor damage.
- The extracted cores may not always be representative of the overall quality of the concrete.
- It requires skilled personnel and specialized equipment for drilling and testing.
- It can be time-consuming and expensive, especially for large structures or projects.

Overall, core testing is a valuable tool for assessing the quality and integrity of concrete structures. It provides direct information about the properties of the concrete and helps in evaluating its strength and durability. However, it should be used judiciously, considering its limitations and the specific requirements of the project.