Integrated Experimental-statistical-numerical Framework for Durability and Fracture Performance of Reactive Powder Concrete under Marine Exposure

Abstract

Reactive Powder Concrete (RPC) is an ultra-dense cementitious material whose durability and cracking behavior in aggressive environments are governed by complex physicochemical mechanisms. This study proposes an integrated experimental-statistical-numerical approach to evaluate the durability of RPC subjected to real marine exposure for 12 months. Response Surface Methodology (RSM) combined with Central Composite Design (CCD) was used to optimize key formulation parameters: cement content, silica fume dosage, superplasticizer dosage, water-to-binder ratio, and fiber volume fraction. Compressive strength and microstructural evolution were evaluated experimentally, while Finite Element Method (FEM) and Extended Finite Element Method (X-FEM) simulations were used to model crack initiation and propagation. Experimental tests showed that optimized RPC mixtures retained high compressive strength with minimal cracking under marine exposure. FEM/XFEM simulations predicted crack initiation and propagation, confirming the effectiveness of fiber reinforcement in reducing crack growth. Statistical analysis highlighted cement content and matrix densification as the most influential factors. This approach provides a comprehensive framework for designing durable RPC formulations for marine environments.