This book is an investigation into the barrier qualities of concrete. The transport of fluids, in particular organic and contaminating liquids, through concrete can lead to water and soil pollution. This is a world-wide problem on which there is little published material. This state-of-the-art report redresses the balance and sets out current knowl

This book is an investigation into the barrier qualities of concrete. The transport of fluids, in particular organic and contaminating liquids, through concrete can lead to water and soil pollution. This is a world-wide problem on which there is little published material. This state-of-the-art report redresses the balance and sets out current knowledge on all aspects of the problem, testing methods and indicates the need for further research.

Durability and service life design of concrete constructions have considerable socio-economic and environmental consequences, in which the permeability of concrete to aggressive intruders plays a vital role. Concrete Permeability and Durability Performance provides deep insight into the permeability of concrete, moving from theory to practice, and presents over 20 real cases, such as Tokyo’s Museum of Western Art, Port of Miami Tunnel and Hong Kong-Zhuhai-Macao sea-link, including field tests in the Antarctic and Atacama Desert. It stresses the importance of site testing for a realistic durability assessment and details the "Torrent Method" for non-destructive measurement of air-permeability. It also delivers answers for some vexing questions: Should the coefficient of permeability be expressed in m2 or m/s? How to get a "mean" pore radius of concrete from gas-permeability tests? Why should permeability preferably be measured on site? How can service life of reinforced concrete structures be predicted by site testing of gas-permeability and cover thickness? Practitioners will find stimulating examples on how to predict the coming service life of new structures and the remaining life of existing structures, based on site testing of air-permeability and cover thickness. Researchers will value theoretical principles, testing methods, as well as how test results reflect the influence of concrete mix composition and processing.

An important new state-of-the-art report prepared by RILEM Technical Committee 108 ICC. It has been written by a team of leading international experts from the UK, USA, Canada, Israel, Germany, Denmark, South Africa, Italy and France. Research studies over recent years in the field of cement science have focused on the behaviour of the interfaces between the components of cement-based materials. The techniques used in other areas of materials science are being applied to the complex materials found in cements and concretes, and this book provides a significant survey of the present state of the art.

Reliable and economical design of Portland Cement Concrete (PCC) pavement structural systems relies on various factors, among which is the proper characterization of the expected permeability response of the concrete mixes. Permeability is a highly important factor which strongly relates the durability of concrete structures and pavement systems to changing environmental conditions. One of the most common environmental attacks which cause the deterioration of concrete structures is the corrosion of reinforcing steel due to chloride penetration. On an annual basis, corrosion-related structural repairs typically cost millions of dollars. This durability problem has gotten widespread interest in recent years due to its incidence rate and the associated high repair costs. For this reason, material characterization is one of the best methods to reduce repair costs. To properly characterize the permeability response of PCC pavement structure, the Kansas Department of Transportation (KDOT) generally runs the Rapid Chloride Permeability test to determine the resistance of concrete to penetration of chloride ions as well as the Boil test to determine the percent voids in hardened concrete. Rapid Chloride test typically measures the number of coulombs passing through a concrete sample over a period of six hours at a concrete age of 7, 28, and 56 days. Boil Test measures the volume of permeable pore space of the concrete sample over a period of five hours at a concrete age of 7, 28, and 56 days. In this research, backpropagation Artificial Neural Network (ANN)-based and Regression-based permeability response prediction models for Rapid Chloride and Boil tests are developed by using the databases provided by KDOT in order to reduce or eliminate the duration of the testing period. Moreover, another set of ANN- and Regression-based permeability prediction models, based on mix-design parameters, are developed using datasets obtained from the literature. The backpropagation ANN learning technique proved to be an efficient methodology to produce a relatively accurate permeability response prediction models. Comparison of the prediction accuracy of the developed ANN models and regression models proved that ANN models have outperformed their counterpart regression-based models. Overall, it can be inferred that the developed ANN-Based permeability prediction models are effective and applicable in characterizing the permeability response of concrete mixes used in transportation applications.

Many concrete structures are not providing the expected service life. Repairs are costly, cause inconvenience to motorists, and raise safety concerns. The durability of concrete depends on, among other things, the ability to resist the penetration of harmful solutions, e.g., chlorides. Recently, pozzolanic materials have been widely used to decrease the permeability of concretes. In this study, the permeability of concretes containing portland cement alone or portland cement with a pozzolan (fly ash, silica fume) or a slag was determined by either the rapid permeability test (AASHTO T 277) or the ponding test (AASHTO T 259). Concretes were tested with either test to determine the reduction in permeability with time. Results show that both tests indicate the permeability of concretes. The rapid permeability test is more convenient and relatively faster than the ponding test. Permeability decreases with time, and the addition of pozzolans or slag is very effective in decreasing permeability.

The Concrete Construction Engineering Handbook, Second Edition provides in depth coverage of concrete construction engineering and technology. It features state-of-the-art discussions on what design engineers and constructors need to know about concrete, focusing on - The latest advances in engineered concrete materials Reinforced concrete construction Specialized construction techniques Design recommendations for high performance With the newly revised edition of this essential handbook, designers, constructors, educators, and field personnel will learn how to produce the best and most durably engineered constructed facilities.