Stochastic approach to modelling the structural failure of strain-hardening fibre-reinforced cementitious composites panels under far-field explosive loading

Stochasticity profoundly influences the explosive response of engineering structures. This study develops a stochastic high-fidelity numerical analysis framework for the far-field explosive response of reinforced ultra-high toughness cementitious composite (UHTCC) members. The framework incorporates comprehensive dynamic constitutive models for both UHTCC and steel reinforcement, together with a dynamic bond-slip relationship between UHTCC and reinforcement. It further captures material uncertainty by introducing spatial variability, spatial auto-correlation, and bivariate cross-correlation of mechanical properties through random fields. Numerical implementation and parameter analyses are carried out for reinforced UHTCC panels subjected to far-field explosion loading. The results indicate that the maximum midspan deflection obtained using the dynamic bond-slip method is greater than that calculated by the traditional penalty method. Moreover, the random field parameters significantly affect the numerical predictions, with most stochastic models yielding larger deflections than the deterministic model. By integrating both detailed reinforcement behaviour and stochastic material fields into a single framework, this study provides a more reliable approach for evaluating the blast resistance of UHTCC structures. Neglecting such stochastic effects may lead to underestimation of structural vulnerability and compromise engineering safety.

Theoretical and Applied Fracture Mechanics, 141, 105285