The Influence of Cracks on the Durability and Service Life of Reinforced Concrete Structures in relation to Chloride-Induced Corrosion: A Look from a Different Perspective

The service life of concrete structures can be significantly shortened when corrosion of steel reinforcement occurs, especially in a marine environment and in structures exposed to de-icing salts. The influence of load- or deformation-induced cracks on corrosion progress is an important issue which was studied in this research in relation to the...

Incorporating cracking of concrete on chloride ingress and service life modeling of concrete structures

Chloride induced reinforcement corrosion is the most common degradation mechanisms for reinforced concrete structures. The service life of concrete structures is normally predicted by estimating the rate of chloride ingress and the necessary time to initiate reinforcement corrosion. Normally, chloride ingress is modeled as a diffusive process in...

Dynamically loaded beam failure under corroded conditions

De-icing salts, used on roads in heavy winters, may enter reinforced concrete (RC) structures via its capillary pore system or via cracks, initiating reinforcement corrosion and reducing its remaining service-life. Vehicles passing real bridges exert a dynamic impact action that might activate a fatigue failure mechanism. In order to generate...

Structural monitoring and modal properties of a real time bridge and lab tests

For understanding the actual state of durability of concrete structures, it is important to know its response due to external loading. This response mainly depends on the actual structural and material properties of the structure, while loaded. Mechanical and chemical degradation are the main mechanisms that may affect these properties with time...

The role of grain size in embrittlement of archaeological silver

Archaeological silver may be embrittled by long-term corrosion and microstructural changes. The embrittlement of artifacts increases with increasing grain size. This is explained by considering the grain boundary character and models describing the interactions between microcracks, lattice dislocations and grain boundaries. Severely embrittled...

Evaluation of non-destructive inspection methods applied to milled step-down areas

The present report describes how fatigue cracks were produced in 102 specimens. After cracking these specimens were inspected non-destructively by means of eddy currents, ultrasonics. X-rays and penetrants, and the indications were recorded. Successively the specimens were exposed to corrosion whereafter the inspections were repeated. Upon...

The significance of cladding for fatigue of aluminium alloys in aircraft structures

Flight-simulation tests were carried out on sheet specimens notched "by an open hole (Kt = 2.66). The material was 2024-T3 in three conditions; Alclad, bare and chemically milled. The crack initiation period and the crack propagation period were considerably shorter for the Alclad material. The significance of the cladding, both for constant...

Heat treatment studies of aluminium alloy type 7050 forgings. Interim report no. 2: The effect of heat treatment on a variety of engineering properties

The effect of variety of heat treatments on various engineering properties was studied with the aim to derive an optimum heat treatment. The engineering properties comprised Vickers hardness, short-time tensile strength, fatigue crack propagation resistance, fracture toughness and stress corrosion resistance. The test results were compared with...