Most GHG emissions in transportation come from on-road vehicles, but construction is a large contributor as well. In particular, concrete manufacturing generates emissions both from energy needed to heat materials in cement kilns and from a chemical process known as “calcination.” Because concrete is so widely used these emissions are substantial, amounting to an estimated 5 percent of the world’s carbon dioxide emissions. A New Jersey-based startup has begun to commercialize a process that it claims reduces GHG emissions by up to 70 percent. The technology relies on lower-emission cement chemistry, and it sequesters carbon dioxide—from a companion industrial or power plant—during hardening.
A Government Accountability Office report issued June 27 outlines the advantages and disadvantages of requiring fiber optic conduit to be installed during construction of certain federally funded highway projects. The report release was preceded on June 13 by an executive order requiring federal agencies to ensure that broadband infrastructure projects, such as those laying fiber-optic cables, coincide with ongoing highway construction whenever possible to reduce private companies’ costs of expanding their high-speed internet networks. The order is similar to legislation introduced in both the House and Senate but never passed.
Accelerated bridge construction (ABC) techniques are transforming the replacement and construction of bridges across the country, and commuters are benefiting from shorter construction schedules. The central component of accelerated bridge construction is the use of prefabrication technologies which allow the production of bridge components off-site.