Concrete is prone to cracking due to its brittle nature and low tensile capacity, which compromises structural durability and service performance. Hybrid fiber reinforcement has emerged as an effective approach to improving crack resistance by combining the complementary advantages of different fiber types. This study investigates the mechanical and crack-resistance performance of hybrid fiber-reinforced concrete (HFRC) incorporating steel fibers (SF) and polypropylene fibers (PPF). A series of mechanical tests were conducted to evaluate the influence of various SF–PPF hybrid combinations. The results show that hybrid reinforcement provides clear advantages over single-fiber systems, particularly in enhancing tensile-related properties. Among all mixtures tested, the combination of 0.8% SF (aspect ratio 80) and 0.10% PPF demonstrates the most balanced performance, achieving notable improvements in crack-resistance indicators while maintaining acceptable workability and cost-efficiency. These findings provide practical guidance for the design and application of HFRC in structures requiring improved cracking control and mechanical reliability.

A novel and rapid ball-milling approach was developed in this study to efficiently intercalate hexadecyltrimethylammonium bromide (HDTMA-Br) into vermiculite (VMT) within only 15 min. The raw granular VMT (2–3 mm) was first ground into fine powder using an airflow pulverizer. A suspension containing VMT and HDTMA-Br (1 CEC) in deionized water was then subjected to planetary ball milling at 450 r/min (25 °C), followed by washing and drying to obtain organo-vermiculite (OVMT) with a particle size of 44–5 µm. X-ray diffraction, Fourier-transform Infrared Spectroscopy and Thermogravimetric Analysis analyses confirmed successful intercalation, with the basal spacing $d_{\left(001\right)}$ expanding from 1.46 nm to 4.51 nm. Transmission Electron Microscopy observations further revealed partial delamination of lamellar structures and a pronounced reduction in particle size, supporting the structural reorganization induced by the mechanochemical process. In addition, nitrogen adsorption analysis showed that the BET surface area decreased by 4.05 m²·g⁻¹, while the average pore diameter increased by 3.2 nm, indicating the development of a more hydrophobic interlayer environment. Overall, this approach offers a practical route for producing organophilic silicate materials and shows strong potential for wastewater treatment applications, particularly for the adsorption of organic pollutants and heavy-metal ions.