Mechanical properties of steel-polypropylene fibre reinforced concrete under elevated temperature

摘要

Fibre reinforced concrete (FRC) has been found to improve strength, ductility, toughness, and durability of the structures. The application of FRC includes tunnel lining, ground slab, facade and many more. However, when exposing them to high temperature such as fire, there is still little information on the impact on its mechanical properties. The main objective of the study is to understand the fundamental behaviour of FRC when it is exposed to elevated temperature. However, rather than relying on one type of fibre, this study proposed of mixing two different types of fibre in concrete which will then be exposed to elevated temperature at normal temperature i.e. 27°C (room temperature), 200°C, and 400°C. The two types of fibres i .e. steel and propylene has different characteristics. The study is mainly focused on the experimental work. The fibre dosage will also be varied with percentage of steel-to-propylene of (100-0), (75-25), (50-50), (25-75) and (0-100) at 15% of fibres proportion from the volume of the concrete. Therefore this research is expected to answer the fundamental question whether if one type is vulnerable to fire, the other one will take place to avoid catastrophic failure of the whole structure. Experimental work will be carried out to study the impact of elevated temperature on the compressive strength, tensile strength, and flexural strength.