Performance Criteria for Concrete Repair Materials


Book Description

The study reported herein is part of an overall investigation to develop performance criteria for cement-based repair materials. In Phase I of the study, preliminary criteria for dimensionally compatible repair materials were developed based on a review of the literature. This review concentrated on identifying pertinent material properties, appropriate test methods, and demonstrated field performance. Laboratory and field tests to evaluate the preliminary performance criteria were conducted in Phase II of the project Twelve candidate repair materials were selected for the experimental portion of the project Bach material was subjected to a series of standard and nonstandard laboratory tests to determine properties which were perceived to be of interest in a repair context and to provide some basic information about their behavior. These tests included: (a) unrestrained and restrained drying shrinkage, (b) modulus of elasticity, (c) tensile and compressive creep, (d) coefficient of thermal expansion, and (e) flexural, compressive, and direct tensile strengths. Concurrent field tests were also conducted to evaluate material durability. Results of the laboratory investigation are described herein. Results of laboratory and field performance tests will be correlated (Phase III) to provide a basis for development of performance criteria for cement-based materials that will provide durable concrete repairs.



















Performance Criteria for Concrete Repair Materials, Phase II Summary Report


Book Description

The results of a study to develop performance criteria for cement-based repair materials are summarized herein. Results of laboratory tests and field performance studies were correlated and guidance for selection of repair materials that would reduce the risk of premature failures was developed. This guidance includes a standard protocol for repair material data sheets and proposed performance criteria. Results of this study illustrate the significant effect of drying shrinkage on the performance of restrained repair materials. While there was a general correlation between the results of laboratory tests on unrestrained shrinkage specimens and field performance, there is a need for restrained shrinkage tests to evaluate the cracking resistance of repair materials. Although there was a general lack of significant correlation between individual material properties and field performance, results of this study indicate that it is possible to predict the field performance of repair materials based on a combination of material properties determined in laboratory tests. Results of this study emphasize the need for a comprehensive analytical model to predict the cracking resistance of repair materials that considers the interrelationship of pertinent material properties, the relative importance of individual properties, and the effect of environmental conditions on time-dependent material properties.




Engineering and Design


Book Description

This manual provides guidance on evaluating the condition of the concrete in a structure, relating the condition of the concrete to the underlying cause or causes of that condition, selecting an appropriate repair material and method for any deficiency found, and using the selected materials and methods to repair or rehabilitate the structure. Guidance is also included on maintenance of concrete and on preparation of concrete investigation reports for repair and rehabilitation projects. Considerations for certain specialized types of rehabilitation projects are also given.