This book presents the work of RILEM Technical Committee 270-CIM: Benchmarking Chloride Ingress Models on Real-life Case Studies - Theory and Practice. It provides a comparative benchmark analysis of various types of chloride ingress models with emphasis on short, medium and long-term predictions. The book is subdivided in five chapters. The first chapter is an introduction on the benchmark and selected cases. The second chapter reports theoretical backgrounds of various analytical and numerical models for chloride ingress, followed by a short description of the models employed in the benchmark analysis. Chapter three describes the benchmark results of the Marine Submerged case, and chapter 4 of the Road Sprayed case. The last chapter reports conclusions, guidelines for calibration and recommendations. The book will benefit academics, designers, engineers, consultants, but also asset owners and standardization committees interested in durability and service life assessment of concrete structures.

This book presents the work of RILEM Technical Committee 270-CIM: Benchmarking Chloride Ingress Models on Real-life Case Studies - Theory and Practice. It provides a comparative benchmark analysis of various types of chloride ingress models with emphasis on short, medium and long-term predictions. The book is subdivided in five chapters. The first chapter is an introduction on the benchmark and selected cases. The second chapter reports theoretical backgrounds of various analytical and numerical models for chloride ingress, followed by a short description of the models employed in the benchmark analysis. Chapter three describes the benchmark results of the Marine Submerged case, and chapter 4 of the Road Sprayed case. The last chapter reports conclusions, guidelines for calibration and recommendations. The book will benefit academics, designers, engineers, consultants, but also asset owners and standardization committees interested in durability and service life assessment of concrete structures.

A harsh, cold, and icy environment is of no surprise to the conditions of a winter climate, where the wide use of de-icing salts on roads and highways allows for the initiation of chloride-induced corrosion of the reinforcement of concrete structures; a reduced service life, loss of structural integrity, visible damages, and ultimately structural failure are among the many unwanted effects of rebar corrosion. Chloride ingress into concrete has been extensively studied for the last four decades; however, most of the relevant research to date does not take into account the effects of sustained loading on chloride transport properties. Therefore, the objectives of this study were to investigate the influence of sustained compressive and tensile stresses on chloride ingress into concrete, and ultimately to understand what the effect of sustained stress is on chloride penetration depth, on chloride concentration by % weight of concrete, and on apparent diffusion coefficients by comparing results to those of unloaded control specimens. To achieve these objectives, six post-tensioned and four non-reinforced control concrete beams were constructed with different water-to-cement (w/c) ratios and completely submerged in a 4-5% de-icing salt (NaCl) solution for 12 weeks, allowing chloride transfer to be completely governed by continuous diffusion. The effects of supplementary cementing material on chloride ingress are also studied. Concrete beams were post-tensioned to induce variable sustained compressive and tensile stresses along the beam. After 12 weeks of exposure, beams were fractured at specific locations and sprayed with a 0.1N silver nitrate (AgNO3) solution to determine average penetration depths; chloride concentration profiles were obtained from potentiometric titration of grinded powder samples. Apparent chloride diffusion coefficients were then obtained from the results of spraying AgNO3 and titration, the latter by non-linear regression curve-fitting to Fick's second law of diffusion. A good agreement between results from both methods reveals that the use of AgNO3 in field is acceptable in predicting the rate of chloride ingress in concrete sustaining stress. The chloride diffusivity for each profile, relative to that of the unstressed section, was related to the compressive and tensile stresses in the concrete section. The experimental results indicate the dependence of chloride ingress and concentration on the type and level of sustained stress. An analysis of the results to study the effects of the w/c ratio using colourimetric (silver nitrate spray) and potentiometric titration methods was also completed.

Chloride ingress in reinforced concrete induces corrosion and consequent spilling and structural weakness, and it occurs world-wide and imposes an enormous cost. Yet it can be resisted by using test methods and relevant models for service life prediction.Resistance of Concrete to Chloride Ingress sets out current understanding of chloride transport

This book is the most comprehensive and flexible theory of chloride ingress in concrete to date. Based on test results and field observations, the book demonstrates the easy application of this theory to practice. The information is presented in a clear style with each chapter containing an introduction, technical applications and examples, and a f

Standards for specifying and ensuring the durability of new concrete structures are commonly of the prescriptive kind. fib Bulletin 76: Benchmarking of deemed-to-satisfy provisions in standards - Durability of reinforced concrete structures exposed to chlorides presents the benchmarking of a number of rules for chloride-induced corrosion as given in national codes such as European, US and Australian standards. This new benchmark determines the reliability ranges in the chloride-induced depassivation of rebar if the deemed-to-satisfy rules of different countries are taken into consideration. It does not only involve (probabilistic) calculations using input mainly based on short-term and rapid laboratory-test data but also involves input based on an independent assessment of existing structures. The reliability analyses are carried out using the probabilistic design approach for chloride-induced corrosion presented in fib Bulletin 34: Model Code for Service Life Design (2006), fib Model Code for Concrete Structures 2010 and ISO 16204:2012. The work compares the calculated reliability ranges thus determined with the target reliabilities proposed by current specifications and, based on the comparison, offers a proposal for the improvement of deemed-to-satisfy rules and specifications. fib Bulletin 76 presents and discusses in detail the input data for the examined model parameters and offers an extensive annexe documenting the values of the individual parameters used in the analyses. It thus provides a reliable database for the performance-based probabilistic service-life design of concrete structures exposed to chlorides, be they in the form of salt fog, sea water or de-icing salts.

The deterioration of reinforced and prestressed concrete structures resulting from the corrosion of the steel reinforcement is a worldwide problem. As long as salt is used for de-icing or structures are built near the coast, chloride will continue to be a primary factor in compromising the durability of a structure. This report deals specifically with the ingress of salt from the environment, which can lead to severe corrosion of reinforcement. It reviews the international state-of-the-art with regard to chloride ingress into concrete and, in particular, considers: - The influence of concreting materials, mix design, curing and environment - methods for the detection of chloride ingress in structures - techniques used for studying chloride ingress