American Concrete Institute

Report on Measuring Mechanical Properties of Hardened Fiber-Reinforced Concrete
 N 544.9R

Annotation

This report documents the determination of mechanical properties of hardened FRC. The objective is to characterize these mechanical properties and encourage common and unified test methods. This objective builds a meaningful database of mechanical properties of hardened FRC materials and products. Further, the results should not be taken out of the context presented for illustrating the tests and not for comparing fibers out of context. The results from the tests and procedures used in this document are not intended to be used for the design of FRC structures. The purpose of this document is to gain a better understanding of the many factors influencing tests for the determination of mechanical properties of FRCs and FRC products.

Although most of the test methods described in this report were developed initially for steel FRC (SFRC), they are applicable to concretes reinforced with glass, synthetic/polymeric, and natural fibers, except when noted. In Fig. 1.2, an example of different types of fibers commonly employed in FRC is provided.

This report applies to the mechanical properties of conventionally mixed and placed FRC or fiber-reinforced shotcrete (FRS) using steel, glass, synthetic/polymeric, and cellulose/ natural fibers.

Some newer test methods and evaluation procedures under development are not included in this report. Examples of this are tensile creep and flexural creep of concrete where the section has cracked and the bridging fibers are carrying loads.

This report does not discuss test methods for thin glass FRC or mortar products produced by the spray-up process. The Prestressed Concrete Institute (PCI MNL 128) and the International Glassfibre Reinforced Cement Association (2016a,b) have prepared recommendations for test methods for these spray-up materials.