Experimental and Numerical Investigation of the Impact Resistance of Synthetic Fiber-Reinforced UHPC Thin Panels

Highlights What are the main findings? center dot Drop-weight impact tests on thin VHPC panels showed that synthetic fiber reinforcement significantly improves impact resistance: PVA microfibers reduced crack openings by more than 20 times compared to plain VHPC, while PP macrofibers were less effective at the tested energy level due to their greater efficiency at larger crack openings. center dot A finite element model based on the fib Model Code 2010 inverse analysis and the Concrete Damaged Plasticity framework accurately reproduced the experimental crack patterns and deflections of all fiber-reinforced panels. What are the implications of the main findings? center dot At low-to-medium impact energy levels, PVA microfibers provide the dominant contribution to impact resistance in thin VHPC panels, suggesting that fiber selection should account for the expected crack opening range under the design impact scenario. center dot The proposed numerical approach, calibrated on quasi-static bending tests, proves adequate for predicting the impact response of thin VHPC panels, offering a reliable and practical tool for structural design.Highlights What are the main findings? center dot Drop-weight impact tests on thin VHPC panels showed that synthetic fiber reinforcement significantly improves impact resistance: PVA microfibers reduced crack openings by more than 20 times compared to plain VHPC, while PP macrofibers were less effective at the tested energy level due to their greater efficiency at larger crack openings. center dot A finite element model based on the fib Model Code 2010 inverse analysis and the Concrete Damaged Plasticity framework accurately reproduced the experimental crack patterns and deflections of all fiber-reinforced panels. What are the implications of the main findings? center dot At low-to-medium impact energy levels, PVA microfibers provide the dominant contribution to impact resistance in thin VHPC panels, suggesting that fiber selection should account for the expected crack opening range under the design impact scenario. center dot The proposed numerical approach, calibrated on quasi-static bending tests, proves adequate for predicting the impact response of thin VHPC panels, offering a reliable and practical tool for structural design.Abstract In recent years, Ultra High-Performance Fiber-Reinforced Concretes (UHPFRCs) have gained significant attention for their applications in structural components, particularly for improving impact resistance and post-cracking behavior. This study explores the behavior of thin Ultra High-Performance Concrete (UHPC) panels reinforced with synthetic fibers, focusing on the potential use of these materials for building fa & ccedil;ades. Three different synthetic fiber-reinforced mixes were developed, utilizing polyvinyl alcohol (PVA) microfibers, polypropylene (PP) macrofibers, and a hybrid combination of both. These thin, unreinforced panels were subjected to impact testing using a free-falling steel ball to evaluate their mechanical response. The results were analyzed in terms of crack patterns, crack openings, and overall impact resistance. Additionally, numerical analysis was implemented by using the ABAQUSTM finite element code, in order to predict the panels' performance under impact, providing a comparison between experimental results and numerical simulations. This investigation highlights the significant contribution of synthetic fibers in enhancing the toughness and impact resistance of UHPC panels, demonstrating their viability for structural applications requiring enhanced durability.