评《混凝土外加剂产品及应用手册》（第二版）蒋家奋混凝土是一项主要的工程材料，随着我国经济建设的发展，这种材料得到了前所未有的快速发展。１９９４年，我国水泥年产量达４亿吨，混凝土年使用量约３０亿吨，居世界第一。然而，混凝土具有一些固有的缺点。为寻求提高... Comment on “Concrete admixture products and application manual” (second edition) Jiang Jiafen concrete is a major engineering material. With the development of our country’s economic construction, this material has achieved unprecedented rapid development. In 1994, the annual output of cement in China reached 400 million tons, and the annual usage of concrete was about 3 billion tons, ranking first in the world. However, concrete has some inherent disadvantages. To seek to improve...