Alkali-silica reaction (ASR) and delayed ettringite formation (DEF) deterioration have been a problem for the concrete infrastructure in the state of Texas and around the world in recent decades. A great deal of research into the causes and mechanisms of the deterioration has helped to prevent the formation of ASR and DEF in new construction, but the evaluation and maintenance of existing structures remains a problem. The goal of this research is to investigate the use of several nondestructive testing (NDT) methods to evaluate the level of ASR and DEF deterioration in a structural element. Based on the results, recommendations are made as to which NDT methods have the most potential to be incorporated into the evaluation process.

Alkali-silica reaction (ASR) and delayed ettringite formation (DEF) are expansive reactions that can lead to the premature deterioration of concrete structures. Both have been implicated in the deterioration of numerous structures around the world, including many transportation structures in Texas. As a result of considerable research advances, ASR and DEF are now avoidable in new construction, but evaluating and managing the existing stock of structures damaged by these mechanisms remains a challenge. While the published guidance for evaluating structures is very effective at diagnosing the presence of ASR and DEF, there remain significant weaknesses with respect to the evaluation of structural safety and serviceability and nondestructive testing (NDT) is a minor component of the evaluation process. The research described in this dissertation involved a wide range of tests on plain and reinforced concrete at multiple scales. This included small cylinders and prisms, larger plain and reinforced concrete specimens in outdoor exposure, full-scale reinforced concrete beams, and core samples from the outdoor exposure specimens and full-scale reinforced concrete beams. Nondestructive test methods were applied at all scales, and the full-scale beams were also tested in four-point flexure to determine the effects of ASR and DEF on flexural strength and serviceability. Severe expansions from ASR and DEF did not reduce the strength of the full-scale beams or result in excessive deflections under live loads, despite significant decreases in the compressive strength and elastic modulus measured from core samples. Most NDT methods were found to be effective at low expansions but had difficulty correlating to larger expansions. Two promising NDT methods have been identified for future research and development, and guidance regarding existing test methods is offered.

This book discusses the behaviour of isolated concrete bottle-shaped struts affected by internal expansion reactions (ISR). For that purpose, the numerical modelling of damaged concrete was performed using the Concrete Damaged Plasticity Model (CDPM) implemented in ABAQUS and validated the model through Sankovich's tests. A procedure to automatically obtain the concrete plasticity and damage parameters, essential for CDPM, was developed in Matlab. The inputs were the characteristic compressive strength of the concrete, the equivalent length of the finite element mesh and the ratio between the plastic and inelastic compressive strains. The results showed that the CDPM could represent the load-bearing mechanisms of isolated concrete bottle-shaped struts for a range of several stress levels to which these elements may be subjected in the panels investigated. The numerical simulations for different expansion levels consistently captured the expected damage profile of the panels and the load corresponding to the formation of the first crack, the estimated crack opening, and the ultimate load. For the panels investigated, the reduction observed in the failure load reached values close to 70%, the increase of the tensile plastic deformation was more than 60%, and the maximum crack opening can reach an increase of 113% when compared with those observed experimentally in panels without internal swelling reactions The book also offers a systematic review of the current state of knowledge and it is a valuable resource for scientists, students, practitioners, and lecturers in various scientific and engineering disciplines, namely, civil and materials engineering, as well as and other interested parties.

Many concrete structures and elements of concrete infrastructure have exceeded their original design lives and are deteriorating to an extent where they are becoming dangerous. The deterioration can be internal or not obvious and therefore only shows up with detailed testing. Non-destructive evaluation of reinforced concrete structures, Volume 1: Deterioration processes and standard test methods reviews the processes of deterioration and classical and standard test methods. Part one discusses deterioration of reinforced concrete and testing problems with chapters on topics such as key issues in the non-destructive testing of concrete structures, when to use non-destructive testing of reinforced concrete structures, deterioration processes in reinforced concrete, modelling ageing and corrosion processes in reinforced concrete structures, components in concrete and their impact on quality, and predicting the service life of reinforced concrete structures. Part two reviews classical and standard testing methods including microscopic examination of deteriorated concrete, the analysis of solid components and their ratios in reinforced concrete structures, the determination of chlorides in concrete structures, and investigating the original water content of reinforced concrete structures. With its distinguished editors and international team of contributors, Non-destructive evaluation of reinforced concrete structures, Volume 1: Deterioration processes and standard test methods will be a standard reference for civil and structural engineers as well as those concerned with making decisions regarding the safety of reinforced concrete structures. Provides a comprehensive discussion from examination of the components in concrete and their affect on quality through to the role of and tools required for lifetime management Experts in the field identify the testing problems associated with infrastructure considering design, build and maintenance stages Presents a guide for when to use non-destructive testing of reinforced concrete structures including the role of time in testing

As critical concrete infrastructure deteriorates, engineers need efficient and reliable techniques to appraise the causes and the extent of deterioration, to evaluate the structural consequences and to select effective management protocols and rehabilitation strategies. This book looks at deterioration caused by internal swelling reaction (ISR) mechanisms in concrete, such as alkali-aggregate reaction, delayed ettringite formation and freeze-thaw cycles. The book provides accessible and comprehensive coverage of recent work and developments on the most common ISR mechanisms leading to induced expansion and deterioration. It addresses the implications of ISR on different scales (micro, meso and macro), outlines qualitative and quantitative techniques to assess the condition of affected concrete and introduces the multi-level assessment protocol, using advanced microscopic and mechanical techniques, particularly the stiffness damage test and damage rating index, as a reliable approach to appraise ISR-affected infrastructure. Also included is a detailed case study of the Robert-Bourassa Charest Overpass in Quebec. Internal Swelling Reactions in Concrete: Mechanisms and Condition Assessment is primarily intended for undergraduate and graduate students, as well as academics interested in the field of concrete durability and condition assessment of concrete. It will also be of interest to engineers and infrastructure owners dealing with ISR-related problems.