Environmental actions on concrete exposed in marine and road environments and its response - Consequences for the initiation of chloride induced reinforcement corrosion

The object of the study presented here has been to describe, further explain and model the influence of the exposure conditions on reinforced concrete structures and the consequences on their expected service life. The focus has been on investigating and quantifying the exposure conditions for structures in marine and road conditions exposed to chloride ions. This has been done by literature studies complemented by field studies, where data on the behaviour of concrete have been gathered and analysed. The literature study has shown that the exposure conditions have a large influence, e.g. due to variations in the severity of exposure to chlorides. Field studies have been made in both marine and road conditions, where the influence of the exposure conditions has been measured as the environmental response of concrete and mortar. In marine conditions identical concrete specimens, exposed at different submerged locations, have been investigated. The results show that the temperature of the seawater has a large influence on chloride ingress. In road conditions both existing structures and specimens have been investigated. The results show that the exposure to chlorides and the chloride ingress into concrete depend on several factors, e.g. height above and distance to the road and surface orientation towards traffic. Service life predictions have been made for structures in marine and road conditions, to exemplify the effect of the exposure conditions. The results of the predictions show that the exposure conditions have a large influence on the expected service life. The predictions also showed that the level of the chloride threshold level, C crit , has a large influence on the predicted service life. The environmental actions, and their variations, have been found to have a large influence on the chloride ingress into and the service life of reinforced concrete structures. Therefore it is not enough to describe these by rough divisions into exposure classes, but instead the true exposure conditions should be taken into account. Preferably each structure should be treated separately, but this is usually not possible. For these structures the methodology described in this thesis can be used to describe and model the environmental actions.

[1]  R. Vitaliani,et al.  Analysis of Chloride Diffusion into Partially Saturated Concrete , 1993 .

[2]  J P Broomfield.  Rebar corrosion: what do we know for sure? , 1997 .

[3]  Luping Tang,et al.  Recurrent studies of chloride ingress in uncracked marine concrete at various exposure times and elevations , 1998 .

[4]  Lars-Olof Nilsson,et al.  Hygroscopic moisture in concrete - drying, measurements & related material properties , 1980 .

[5]  Rw McGee.  Modelling of Chloride Ingress in Tasmanian Bridges , 2000 .

[6]  Paul Sandberg.  Critical evaluation of factors affecting chloride initiated reinforcement corrosion in concrete , 1995 .

[7]  A. Lindvall.  Chloride ingress data from field exposure, at twelve different marine exposure locations, and laboratory exposure , 2003 .

[8]  Lars-Olof Nilsson,et al.  Chloride ingress data from field exposure in a Swedish road environment , 2001 .

[9]  J. Monteith,et al.  Boundary Layer Climates. , 1979 .

[10]  E Burley,et al.  SERVICE LIFE PREDICTION OF CONCRETE BRIDGES , 1996 .

[11]  Eva Harderup,et al.  Klimatdata för fuktberäkningar : väderdata från tio meteorologiska mätstationer i Sverige , 1995 .

[12]  Steinar Helland,et al.  Chloride Penetration into Concrete with Lightweight Aggregates , 2000 .

[13]  Rüdiger Rackwitz,et al.  Zuverlässigkeitsbetrachtungen bei Verlust der Dauerhaftigkeit von Bauteilen und Bauwerken - T2847 , 1999 .

[14]  K. Tuutti.  Corrosion of steel in concrete , 1982 .

[15]  Wolfgang Brameshuber,et al.  Probabilistische Lebensdauerbemessung von Stahlbetonbauwerken : Zuverlässigkeitsbetrachtungen zur wirksamen Vermeidung von Bewehrungskorrosion , 2000 .

[16]  K. Takewaka,et al.  Quality and Cover Thickness of Concrete Based on the Estimation of Chloride Penetration in Marine Environments , 1988, SP-109: Concrete in Marine Environment.

[17]  P. Kelsey,et al.  DEICING SALT DISPERSION AND EFFECTS ON VEGETATION ALONG HIGHWAYS . CASE STUDY: DEICING SALT DEPOSITION ON THE MORTON ARBORETUM. IN: CHEMICAL DEICERS AND THE ENVIRONMENT , 1992 .

[18]  Robert A. Fitzpatrick.  Corrosion Of Concrete Structures In Coastal Areas , 1996 .

[19]  S.J.H. Meijers.  Computational Modelling of Chloride Ingress in Concrete , 2003 .

[20]  A. Högberg,et al.  Microclimate description : to faciliate estimating durability and service life of building components exposed to natural outdoor climate , 1998 .

[21]  Lars-Olof Nilsson,et al.  Interaction between microclimate and concrete —a prerequisite for deterioration , 1996 .

[22]  W G Ryan,et al.  CONCRETE IN THE MARINE ENVIRONMENT , 1990 .

[23]  Joost Walraven,et al.  Coefficient of diffusion derived from structures exposed to chlorides more than 60 years old , 2003 .

[24]  G. Blomqvist,et al.  Airborne spreading and deposition of de-icing salt : A case study , 1999 .

[25]  Samson,et al.  Numerical Solution of the Extended Nernst-Planck Model. , 1999, Journal of colloid and interface science.

[26]  James J. Beaudoin,et al.  Modeling chemical activity effects in strong ionic solutions , 1999 .

[27]  Leif Mejlbro,et al.  The Complete Solution of Fick's Second Law of Diffusion with Time-dependent Diffusion Coefficient and Surface Concentration , 1996 .

[28]  J.G.M. Wood,et al.  Tay road bridge: Analysis of chloride ingress variability & prediction of long term deterioration , 1997 .

[29]  Tang Luping,et al.  Chloride Transport in Concrete - Measurement and Prediction , 1996 .

[30]  A. Lindvall.  Mapping of the chloride load around two Swedish reinforced concrete bridges , 2002 .

[31]  Adrian Long,et al.  Why assess the properties of near-surface concrete? , 2001 .

[32]  Luping Tang.  Chloride Penetration Profiles and Diffusivity in Concrete under Different Exposure Conditions , 1997 .

[33]  M. Morcillo,et al.  Salinity in marine atmospheric corrosion: Its dependence on the wind regime existing in the site , 2000 .

[34]  Mette Rica Geiker,et al.  Chloride diffusion in partially saturated cementitious material , 2003 .

[35]  P. Sandberg.  Studies of chloride binding in concrete exposed in a marine environment , 1999 .

[36]  Paul Sandberg,et al.  Chloride initiated reinforcement corrosion in marine concrete , 1998 .

[37]  Lars-Olof Nilsson,et al.  Chloride binding capacity and binding isotherms of OPC pastes and mortars , 1993 .

[38]  C. Andrade,et al.  Chloride threshold values to depassivate reinforcing bars embedded in a standardized OPC mortar , 2000 .

[39]  Michael D.A. Thomas,et al.  An overview and sensitivity study of a multimechanistic chloride transport model , 1999 .

[40]  Anders Lindvall,et al.  Undersökning av kloridinträngning, armeringskorrosion, frysning och fukttillstånd på sju brokonstruktioner exponerade för tösalter , 2000 .

[41]  E. Samson,et al.  Modelling ion diffusion mechanisms in porous media , 1999 .

[42]  Brad Violetta,et al.  Life-365 Service Life Prediction Model , 2002 .

[43]  Per Freiesleben Hansen,et al.  Chloride ingress in cement paste and mortar , 1999 .

[44]  M. Gustafsson,et al.  Inland transport of marine aerosols in southern Sweden , 2000 .

[45]  C. L. Page,et al.  Diffusion of chloride ions in hardened cement pastes , 1981 .

[46]  Edward A. McBean,et al.  MIGRATION PATTERN OF DE-ICING SALTS FROM ROADS , 1987 .

[47]  J. S. Hunter,et al.  Statistics for Experimenters: An Introduction to Design, Data Analysis, and Model Building. , 1979 .

[48]  G. L. Balázs,et al.  Kinetic method to analyse chloride diffusion in various concretes , 1994 .

[49]  Olivier Truc,et al.  Prediction of Chloride Penetration into Saturated Concrete Multi-Species Approach , 2000 .

[50]  E J Wallbank,et al.  The Performance of Concrete in Bridges: a Survey of 200 Highway Bridges , 1989 .

[51]  Göran Blomqvist,et al.  IMPACT OF DE-ICING SALT ON ROADSIDE VEGETATION. , 1998 .

[52]  D. Cleland,et al.  Assessment of the durability of concrete from its permeation properties: a review , 2001 .

[53]  Anders Lindvall,et al.  Environmental Actions and Response - Reinforced Concrete Structures exposed in Road and Marine Environments , 2001 .

[54]  Dale P Bentz.  A COMPUTER MODEL TO PREDICT THE SURFACE TEMPERATURE AND TIME-OF-WETNESS TEMPERATURE OF CONCRETE PAVEMENTS AND BRIDGE DECKS. , 2000 .