In new construction, cracks can appear for variety of reasons: curing, temperature deviation, pressure from adjacent conditions, or settlement. This presentation will outline various types of cracking, how to plan to avoid them, and how to address them after concrete has been placed.
Industry questions related to moisture-related floor covering and coating failures will be answered by the presenter during a 1-hour webinar. Questions will come from ICRI members through a survey conducted prior to the webinar and PPT slides addressing the questions prepared by the presenter. Questions from webinar attendees will also be answered during the webinar.
Matching concrete sounds simple, but there are many factors that affect color, texture, and aesthetics. There is often a challenge with using modern cementitious materials for matching older and historically manufactured cements. Whether your project is historic or contemporary, this presentation will outline materials and methodology that are important to understand when concrete matching is important. With many mid-century buildings coming of repair age, this is a critical time for understanding these concepts. The presentation will include the fundamentals of concrete materials, how cementitious materials affect concrete color, how to use color measurement technology in developing a color match mix design, how aggregate exposure affects aesthetic perception, and other helpful tips when it comes to matching concrete for durable and aesthetic results. Regionally available materials will vary, but the methodology for color matching durable repairs is fundamentally the same.
Concrete is the most widely used construction material and can be durable for hundreds of years; however, the main cause of concrete deterioration is from corrosion of reinforcing steel. Steel is thermodynamically unstable and will eventually oxidize to a lower energy state. The rate of deterioration in new and existing structures can be modeled to predict the service life based on the severity of the service environment, the concrete quality, the ingress of deleterious materials, and other factors to various degrees of success. This presentation will provide an overview of many of the service life models currently in use and provide an evaluation protocol for their application related to both new and existing structures.
From the days of boiled Linseed oil, to the discovery of membrane forming cures, to the development of carbon dioxide injection; curing has evolved to accommodate the demands of the construction industry. This presentation will look back at the early standards developed by ASTM, contrasting them to the standards that are currently under consideration. There are many ways to cure concrete, this presentation will review the various product options framed in the context of weather. Lastly, the presentation will explore the various methods discussing the features and benefits of the common curing practices of today.
Repairing and extending the service life of concrete in severe environments first requires that one understands what may be considered severe why it may be considered so. This presentation will discuss the ways in which different organizations and technical committees around the world define ‘severe environments’ for concrete structures; types of deterioration mechanisms and materials-related distress that may severely and quickly deteriorate concrete, type of structures with potentially severe environments, and U.S. geographical considerations.
The case-histories based presentation will focus on the use of nondestructive evaluation (NDE) methods to detect flaws and damage in concrete construction. Case histories will be presented for detection and mapping of flaws and damage in concrete such as cracking, delamination, honeycomb, void, corrosion, fire damage, alkali-silica reaction and low strength concrete. The case histories for the concrete structures are anticipated to include parking structures, bridges, buildings and dams. NDE methods will include sonic/ultrasonic, infrared thermography, radar and corrosion technologies where the results in many cases were confirmed by coring. The use of some of the NDE methods for QA of concrete repairs such as epoxy injection and patching will also be discussed.
Two projects will be explored in this presentation. The first is a concrete structure which for 20 years was exposed to extreme heat. The second is a structure which was exposed to extreme vibrations. Both these structures were integral parts of manufacturing processes and required limited down time to repair. The questions needing to be answered were: what is the condition of the existing concrete and what are the repair options for these structures. We turned to non-destructive techniques to evaluate these structures. Non-destructive techniques can provide insight into structures when accompanied by experienced engineers and petrographic analysis. Repair options were provided at the end of our evaluation leading to reduced down time and well-planned repairs.
Shotcrete has been used widely for rehabilitation and retrofit of concrete structures. More and more large infrastructures, in particular, in the hydro power industry, is using shotcrete for major rehabilitation and retrofit. Recently, the US Army Corps of Engineers has been engaged in structural modifications to reinforced concrete draft tube exits from the turbines in the Ice Harbor Lock and Dam located on the Snake River, Washington. This presentation details the structural modification to the draft tube which was successfully completed using wet-mix shotcrete.
ICRI in-person conventions consist of numerous networking opportunities. In many cases, we catch up with old friends who we have not seen in a while, and get to know new friends. Great stories abound, including how ICRI members came to be involved in the organization. Tune in to hear some of these stories in a relaxed, “sitting-at-the-bar” exchange among notable ICRI leaders.