# Real-Time Temperature Effects on Dynamic Impact Mechanical Properties of Hybrid Fiber-Reinforced High-Performance Concrete

## TL;DR

This study examines how different fiber-reinforced concretes behave under high temperatures and impact, finding that hybrid systems offer better performance in extreme thermal conditions.

## Contribution

The study introduces a temperature-adaptive design strategy for hybrid fiber-reinforced concrete under thermo-shock coupling.

## Key findings

- Hybrid SF-PVAF systems showed stable dynamic strength between 200–400 °C due to synergistic toughening mechanisms.
- SF-PPF combinations are recommended for 400–500 °C environments based on compressive strength trends.
- Microstructural analysis confirmed collaborative failure mode optimization through organic fiber pores and SF crack-bridging.

## Abstract

Metallurgical equipment foundations exposed to prolonged 300–500 °C environments are subject to explosion risks, necessitating materials that are resistant to thermo-shock-coupled loads. This study investigated the real-time dynamic compressive behavior of high-performance concrete (HPC) reinforced with steel fibers (SFs), polypropylene fibers (PPFs), polyvinyl alcohol fibers (PVAFs), and their hybrid systems under thermo-shock coupling using real-time high-temperature (200–500 °C) SHPB tests. The results revealed temperature-dependent dynamic responses: SFs exhibited a V-shaped trend in compressive strength evolution (minimum at 400 °C), while PPFs/PVAFs showed inverted V-shaped trends (peaking at 300 °C). Hybrid systems demonstrated superior performance: SF-PVAF achieved stable dynamic strength at 200–400 °C (dynamic increase factor, DIF ≈ 1.65) due to synergistic toughening via SF bridging and PVAF melt-induced pore energy absorption. Microstructural analysis confirmed that organic fiber pores and SF crack-bridging collaboratively optimized failure modes, reducing brittle fracture. A temperature-adaptive design strategy is proposed: SF-PVAF hybrids are prioritized for temperatures of 200–400 °C, while SF-PPF combinations are recommended for 400–500 °C environments, providing critical guidance for explosion-resistant HPC in extreme thermal–industrial settings.