Thermo-mechanical evaluation of hybrid basalt fiber aerodrome concrete pavement under dynamic impact

The object of research is the thermo-mechanical behaviour of hybrid basalt fibre-reinforced concrete used in aerodrome pavements. The subject of the research is the effect of hybrid fibre composition on impact resistance and thermal durability under dynamic loading. The purpose of the research was to develop and assess a hybrid basalt fibre mix capable of enhancing the mechanical and thermal stability of airfield pavements. Method. Three concrete mixes were selected: a control mix (K, 0% fibre), a micro-fibre mix (2A, 2% micro-fibre), and a macro-fibre mix (2B, 2% macro-fibre). The mechanical properties, specifically the Modulus of Elasticity, were modelled as a function of temperature and using reduction factors based on existing building standards (Eurocode 2: EN 1992−1-2). A linear static analysis was performed for 12 cases (3 mixes, 4 temperatures) using Autodesk Robot Structural Analysis software. The pavement was modelled as a slab with elastic soil supports (Winkler foundation). Two cumulative load cases were applied: a static uniform pressure of over an area and a uniform temperature increase. The primary output parameters were Total Displacement and Maximum Bending Moment. Results. The results indicate that high temperature is the most governing factor in the slab's structural behaviour, causing a varied reduction in material stiffness. This thermal degradation led to a gradual and dramatic increase in maximum vertical displacement, which rose from a baseline of at (Mix K) to at across all three mixes. Crucially, at high temperatures, the reinforcing action of both micro- and macro-basalt fibres was rendered insignificant because the failure mode was completely governed by the thermal degradation of the cement matrix itself. The maximum bending moment exhibited a non-linear relationship with temperature, initially decreasing due to stiffness loss, but then increasing sharply at (to for Mix K) due to significant thermal stresses and warping effects, indicating a state of critical distress.