"Bendable Concrete" Replaces Bridge Expansion Joints

DOTs across the nation face potential failure of mechanical expansion joints installed between adjacent simple span bridge decks. These joints are necessary to accommodate the many types of necessary movements of the bridge decks caused by variations in temperature, vehicle loads, or settlement. In addition, bridge joints need to withstand traffic loads and provide good riding quality while producing minimal noise. Joints that fall into disrepair can lead to the deterioration of the entire structure.

To allow designers to maintain simple span designs, and to permit retrofitting of existing bridge structures, the use of “Engineered Cementitious Composites (ECC) Link Slabs,” rather than mechanical expansion joints, was proposed by the University of Michigan researchers to MDOT. ECC has been shown to limit cracking as well as exhibit high ductility. This ductility has led to ECC being called “bendable concrete.” More.

A demonstration ECC link slab was completed by MDOT on the Grove Street Bridge over I-94 in Ypsilanti, Mich. in November 2005. More.

Fundamentals of Bendable Concrete
December 5-7,2006, Ann Arbor, Mich.
This two and a half day course is designed to transfer the knowledge and know-how to engineers and industry professionals interested in bendable concrete and its creative use in enhancing structural and product performance. More.

Ultra-High Performance Concrete: Annotated Bibliography ( LB27 )
Contains 150 citations to journal articles, conference papers, and reports on Ultra-High Performance Concrete (UHPC). With its exceptionally high durability, compressive strength, minimal long-term creep or shrinkage, resistance to freeze-thaw, and economic benefits, UHPC is regarded as well suited for use in highway bridges, high-rise buildings, and other structures that call for thinner, lighter properties with high strength. More.

Sealer Options for Concrete Countertops

Since concrete is such a versatile material, more and more people are realizing its value for making countertops. Shapes of concrete countertops are only limited by imagination and the ability to build the forms. With the use of color pigments in combination with white cement and various aggregates, the spectrum of colors available in concrete countertops is virtually limitless. More.

Unfortunately, there is a belief that concrete countertops stain easily and require extensive maintenance to keep them functional. Proper sealing of concrete countertops can eliminate 99% of these issues. For a comprehensive look at the sealants available for use in concrete countertops, click here. (PDF)

Click here for more about white cement and decorative concrete.

We are planning to build a concrete countertop. Can you tell me which type of cement to use for this application? I’ve heard that Type II is best.

A: The recommendation to use a Type II cement for countertop construction is usually based on the premise that concrete with a Type II cement will have lower shrinkage potential and, therefore, lower cracking potential. While there may be slight variations in shrinkage potential between cements from different manufacturers and between cement types, it is of little practical value to limit the cement type based on this fact. More.

Click here for more cement and concrete FAQs.

Supplementary Cementing Materials for Use in Concrete
September 26, 2006, Charlotte, N.C.

This new one-day regional program will explore the use of supplementary cementing materials (SCMs) and their impact on the durability, workability, economy, and sustainability of concrete. An excellent course for industry professionals who use concrete as a building material, this course provides a comprehensive overview on the most common SCMs used in concrete construction: fly ash, GGBF slag, silica fume, and natural pozzolans. Topics include the production process, physical and chemical composition and their effects on both the fresh and hardened properties of concrete. More.

For a complete listing of industry conferences, click here.

What to Expect When You're Inspecting, Parts I & II (DVD125)
This new DVD version of the popular PCA videos, presents an overview of the purpose and function of the concrete inspector using real-world situations. Part I focuses on the inspector's role prior to concrete placement and Part II looks at the inspector’s role after the concrete has arrived on site. More.