Webinars Archive

What is mass concrete? ACI 207.1R defines mass concrete as any volume of concrete with dimensions large enough to require that measures be taken to cope with the generation of heat from hydration of the cement and attendant volume change to minimize cracking. But how does one predict whether mass concrete problems will occur and what steps should be taken? This presentation will discuss how to identify mass concrete, ACI 301 requirements pertaining to it, and good construction practices. Topics covered in this presentation will include: Examples of mass concrete structures Identifying mass concrete in the field Specification requirements Factors influencing mass concrete Show less

Recycled concrete aggregate (RCA) is crushed concrete used to replace virgin aggregate in new concrete. With impending aggregate shortages and a push for more sustainable concrete, interest in using RCA is very high. There have been numerous projects using RCA, but what do we actually know about it? This presentation will review what RCA is, how and why it affects new concrete, and the wide range of effects using RCA can have. Recent research on using RCA at low replacement levels will be briefly shared. Show less

The presentation will provide background on safe rooms and storm shelters as well as their performance objective, current design references, and where they are required in the IBC and IEBC. We will explore how design and construction criteria for safe rooms and storm shelters result in resilience to tornadoes and hurricanes and provide enhanced sustainability for communities. Precast and cast in place examples will be shared. Show less

Concrete is the second most used material in the world, only exceeded by water. It is also one of our oldest construction materials starting thousands of years ago. It continues to evolve and allows us to make the tallest buildings, bridges, and roadways. So how did our ancestors find out that if we heated rocks, we could make cement and then make concrete? How did we discover the multi-step process of making our modern concrete? This presentation will take us through the journey of how cement and concrete developed. Along this journey, we will see how the discovery of fire, bricks, pottery, pyramids, and lighthouses played a major role in the development of concrete. Show less

It is becoming increasingly common for developers and the AEC community to establish carbon reduction goals for projects, in addition to other sustainability targets. Policies are being put in place that set carbon footprint limits on certain materials. In this session we will review the current landscape of embodied carbon and sustainability, how to calculate the carbon footprint of your scope on a project and discuss availability of local materials and strategies to reduce embodied carbon of concrete, including specific strategies to incorporate in specifications. We will also discuss how the ready-mix supplier can support the industry on a project that has carbon reduction goals. Show less

Many issues related to construction can be alleviated by a fundamental understanding of the basics of concrete. This starts with knowledge of the standard components of a concrete mixture including cementitious materials, aggregates, water, and admixtures and their importance on the properties of fresh and hardened concrete. The combination of these materials in various proportions can produce mixtures suitable for a wide range of applications and placement methods. Once placed, the concrete must be properly cured to develop its intended properties. This presentation introduces the basics of concrete and describes its importance and application as a construction material. Show less

This presentation by Luke Snell, P.E. and an Honorary Member of ACI will take us step by step through the process of how to make a decision with core test results. Remember everyone is on edge when cores are needed – the concrete may be below strength and correction measures even removed may be needed! Show less

Forms, shores, and re-shores are a temporary structure that carries the weight and construction load of the permanent structure until it is strong enough to stand up for itself. While serving this temporary duty, forms, shores, and re-shores impact construction safety, cost, productivity, and schedule, and influence appearance, deformations, tolerances, and cracking of the hardened reinforced or prestressed concrete. This presentation introduces Codes, standard specifications, OSHA, and ANSI documents that address responsibilities for forms and shores. By an example of a multi-story building, we look at how shore and re-shore systems work, including how shoring & re-shoring plans must be synchronized with rate-of-strength-gain of the concrete, as influenced by mix-design and ambient temperature. This complex topic demonstrates how schedule, concrete mix, weather, construction technology, lab and in-place testing all come together. Show less

This presentation will introduce the work of NEU, an ACI Center of Excellence for Carbon Neutral Concrete, and discuss the important role of concrete in reaching carbon neutrality. The presentation will provide an overview of key terms and concepts, the latest information on green concrete codes, and examples of low carbon practices for the concrete industry for the present and future. Show less

The concrete industry has a goal of carbon neutrality by 2050. In response to this goal, many industry organizations are tasked with getting their message related to decarbonization and sustainability to their customers, specifiers, and employees. Transparency and recognition of goals and achievements are vital. Kimberly will discuss a variety of methods and materials that should be used to effectively communicate progress. Kimberly will help you identify key ways to communicate the steps your organization is taking, whether that be in the form of a new product or innovative process, that will help your organization reach your sustainability goals. Show less