The following information can be obtained with further assessment of cores:ġ- Compressive strength: Perhaps, measurement of compressive strength is the primary objective in most cases. Coring can also be used as a means of quality control when things go wrong with concrete material quality or the pouring and curing process. Taking core samples provides invaluable information about an existing structure. permeability, protection against radiation), the number of cores should be very limited. The location of cores can be adjusted to reduce the impact on aesthetic features.Ĥ- Durability concerns: when durability of concrete (i.e. mid-span for the beams, or any face near the top of lifts for vertical elements).Ģ- Highly reinforced or slender members: when the element is highly reinforced, or coring can significantly affect the integrity or structural performance, the cores should be taken from nearest non-critical sectionģ- Aesthetic consideration: concrete coring can leave unpleasant scenes on the structure. The type of condition assessment also plays a key role in selecting the location of cores.ġ- Likely strength/stress: when the objective of an assessment is to evaluate the structure under service loads, the cores should be taken from areas where the minimum strength and maximum stress coincide (i.e. It is safe to say that increasing the number of cores can deliver a more realistic distribution of strength, but at the same time, leave more weak points in concrete. The cores should also be a realistic representation of concrete quality.
The quantity and the location of cores should be selected such that they represent the strength distribution within the member. To make coring more efficient, one needs to address the following challenges:ġ- How many cores are needed? ,and where? We will also discuss how non-destructive testing has changed the paradigm in recent years.Ĭoring in concrete structures come with certain challenges. In this article, we will review the benefits and disadvantages of taking cores. In addition, the selection of core locations in structure can be a challenging task. However, with all the benefits coring brings to the table, coring has certain disadvantages. The procedure for taking core samples and testing them has been standardized ( ASTM C 42, and ACI 318). The compression test on core samples is known as the most reliable method for assessing the compressive strength and a means of quality control. Taking core samples from concrete structures is required for comprehensive assessment of durability and structural performance of the structure.