This article starts with a good historical description of why concrete is essential to modern civilization but then bemoans it environmental impact, noting that concrete produces 5 percent of global CO2 emissions—as much as the entire country of Russia. But there's hope!
Recent research suggests that when it comes to concrete, we can do better. Several universities and corporations have set up research partnerships to make concrete more sustainable. In 2014, engineers at the Massachusetts Institute of Technology reported that by tweaking the ratio of starting ingredients, they had created cement samples with twice the strength of standard Portland cement. Franz-Josef Ulm, director of MIT's Concrete Sustainability Hub, says that stronger materials allow engineers to make do with less total cement—potentially achieving the same construction goals while emitting 60 percent less CO2.