Epoxy types vary widely, and specifiers need to note such attributes as nozzle time, gel time, load time, sag, cure time, and chemical resistance—each property will affect what makes the product ideal for the intended application. When searching for the proper epoxy to specify, it is important to note there are three general classes—pure epoxy, polyester resins, and epoxy acrylates—that break out in different ways with respect to properties and performance.
Bearing pads are used widely in precast concrete parking garages. They function as buffers between the separate concrete members to prevent damage and facilitate movement (much like cartilage between bones at joints). Bearing pads should last for the design life of the structure, but need to be replaced when they are not sufficiently durable. The ‘surgery’ to replace the pads properly is a complex operation, with few published guidelines.
Resisting natural disasters and reducing environmental impacts are major challenges in the United States. During an average year, there are 10 tropical storms (six of which become hurricanes) and more than 1200 tornadoes touching down. In South Florida, Hurricane Andrew left a wake of destruction in 1992 that totaled more than $25 billion in property damage and resulted in 44 fatalities.
Designing proper construction details is an important part of architecture and engineering practice that involves more than just a grasp of building technology. If designers are not also alert to market conditions, then their details—no matter how elegant—can be ineffective and hinder the pace of a project. Overlooking the complications surrounding the specification of adhesive anchors is a prime example, as recent code changes regarding their use threaten to stall building projects in some of the United States’ largest jurisdictions.
This article explores some of the benefits realized through the speed of construction enabled by specifying insulating concrete forms (ICFs)—a technology that combines reinforced concrete with thermal insulation. The piece profiles diverse projects—a school, a multi-family midrise, a big box, and a hotel—in detailing the cost efficiencies. It also looks at ICF design possibilities, installation techniques, and accessory products.