Analysis of flow rates in cracked reinforced concrete

Abstract

According to Eurocode 2, part 3, autogenous self‐healing of separation cracks with a width ≤0.20 mm can be considered under certain hydraulic conditions. However, practical experience shows that healing does not always reliably occur even when this crack width is maintained. This study examines the flow rates of centrally cracked and water‐permeated concrete using Edvardsen's method. An analytical approach following Hagen–Poiseuille is developed to estimate the flow rate immediately after the start of the water flow Q₀, which is particularly relevant for tightness class TC0. In addition to the water pressure, Q₀ is influenced by the crack width distribution across the cross‐section, the roughness of the crack flanks, and the tortuosity of the crack path. Therefore, a reliable estimation of the flow rate necessitates the introduction of a correction factor ξ, which is proposed with 0.52 due to the high variability of the experimental data.