Concrete Admixture Matrix for Northern Nevada and California
This technical memorandum has been compiled by the SNCA Technical Committee to help with the most common mixture applications you would find in our region. The SNCA Technical Committee can also set up a brief workshop on the variety of commonly available ad mixes and their uses in the area. Contact Us to set up a workshop.
Concrete Durability Recommendations
This memorandum on recommended concrete properties for freeze/thaw, salt and sulfate exposure has been prepared by the SNCA Technical Committee. While not a complete guide, selection and curing it should be used in conjunction with ACI, ASTM, PCA and local standard requirements. These recommendations apply both to public works and residential construction.
MIT’s New Methodology for Life Cycle Assessment of Pavements
The Massachusetts Institute of Technology’s Concrete Sustainability Hub: The Effects of Inflation and Its Volatility on the Choice of Construction Alternatives reveals new tools to determine lLife cycle cost analysis (LCCA,) which assesses the total cost throughout the life of a construction project. In the case of a road or highway, it includes not just the cost of initial construction, but the future cost of maintenance and rehabilitation required during the useful life of the project.
- LCCA has become one of the most important tools available to transportation agency officials in evaluating paving materials and in making informed choices that best serve the public interest.
- It is a process that is recommended by the Federal Highway Administration (FHWA) because it saves taxpayers millions of dollars, improves roadway performance, and makes decision-making a far more transparent process.
The research presented here is part of an ongoing project by the LCA team at the MIT Concrete Sustainability Hub. More information, including the full report, Methods, Impacts, and Opportunities in the Concrete Pavement Life Cycle, can be found online at http://web.mit.edu/cshub.
Engineered Cementitious Composite (ECC)
Engineered cementitious composites (ECC) is a high-performance fiber-reinforced mixture of cement, water, fine sand, fibers, and chemical admixtures. The fibers are typically polyvinyl alcohol fibers (PVA). ECC performs very similar to concrete in compression; ECC can reach the same compressive strengths as concrete. However, ECC has superior tensile properties. ECC can have a tensile strain capacity of 5%, about 500 times larger than that of concrete. The same ECC mix can have a tensile strength of over 725 psi (5 MPa). Tests performed on ECC show the material has many characteristics that engineers desire: high corrosion resistance, high resistance to reflective cracking, low permeability, high freeze-thaw resistance, and high ductility. The use of ECC has grown as engineers have seen the benefits of ECC. Click here for a full repot on ECC from the University of Nevada, Reno for the Nevada DOT to determine whether or not ECC can be produced consistently and reliably from multiple sources of Nevada aggregates and batched on a large scale for highway construction projects.