Effect of Exposure to High Temperature on the Mechanical Properties of SIFRCCs

Abstract

Many researchers have studied explosion prevention and fire resistance of high-strength concrete mixed with organic fiber and steel fibers. The fire resistance of high-performance fiber reinforced cement composites is desirable in terms of physical and mechanical properties. However, the use of a polymer as an alternative to organic fiber has not been clearly studied. In this study, a slurry infiltration method was used to obtain slurry-infiltrated fiber-reinforced cementitious composites (SIFRCCs) specimens. Powder polymer was used instead of organic fibers during mixing of the slurry. The compressive and flexural strengths of the specimens after 1 hr of high temperature exposure according to the KS F 2257 (ISO 834) standard fire-temperature curve were measured. The addition of the polymer before and after high temperature (about 945 °C) exposure affected the strength of the SIFRCCs. The compressive and flexural strengths were decreased after exposure to high temperature in comparison with SIFRCCs without polymer because polymer create capillary pores due to melting and burning when exposure to high temperature. This minimizes the vapor pressure inside the concrete model and reduces the failure of the concrete model. The experimental results showed that the flexural strength at a high temperature for 1.0 % polymer content was the highest at 53.8 MPa. The flexural strength was reduced by 40~50% when compared to the flexural strength before high temperature exposure and comparing to SIFRCCs without polymer, the compressive strength in 1.5% polymer is lower, owing to voids that are created in the SIFRCCs after exposure to a high temperature.

Identification of Destruction Processes and Assessment of Deformations in Compressed Concrete Modified with Polypropylene Fibers Exposed to Fire Temperatures Using Acoustic Emission Signal Analysis, Numerical Analysis, and Digital Image Correlation

“…The research results show that the mechanism of polypropylene fibers, due to the fact that they melt at a temperature of 170 • C and create a porous structure, reduces the build-up of pore pressure inside the heated concrete structure [22][23][24][25]. They prevent spalling better than steel fibers, although they negatively affect other mechanical properties of concrete because they reduce the remaining compressive strength, elastic modulus, and tensile strength of the fired concrete [15,26].…”

Stress-Strain Behavior of Normal and High-Strength Steel-Fiber Concrete Post Burning

“…Zaidi et al [21] and Korsun et al [22] started researching the post-burning fibrous concrete and they had succeeded in developing a model of confined fibrous concrete at elevated temperatures. Antonius et al [23], Kim et al [24] also studied the ductility behavior of steel-fibrous concrete beams at various temperatures, and it was concluded that the ductility of the structure decreased compared to the ductility of the structure without being burned, but the decrease in the ductility value was insignificant. In other structural fields, the post-combustible shears ability of steelfibrous concrete has also been studied [25][26][27].…”

Post-Fire Mechanical Properties of Concrete Reinforced with Spanish Broom Fibers

“…Concrete is a composite material that is widely used in buildings, industrial infrastructure, and other applications around the world. Nowadays, structures are increasing in size and complexity [1]. This has led to developments in fiber-reinforced concrete to overcome the limitations of conventional concrete.…”

“…Although concrete, as an inert material, performs better at high temperatures and has a higher capacity to endure fire than other materials due to its low thermal conductivity and non-combustibility, the damaging impacts of fire on the mechanical properties and durability of concrete remain a concern to many researchers [1,4]. Some of the types of fire damage to concrete include explosive spalling, strength loss, and cracking [5].…”

“…Steel fibers can support the structure of concrete at high temperatures due to their high melting point [1]. A previous study [7] showed that the more steel fibers included in the concrete, the higher the compressive strength at high temperatures.…”