Markets: Ready-Mixed Concrete
预拌混凝土因价值重量比低且易硬化，运输受限极大，必须就近生产。本文介绍美国预拌混凝土市场的基本情况，聚焦其消费者与生产者，并辅以国际对比。
Concrete's natural color is gray. Its favored uses are utilitarian. Its very ubiquity causes it to blend into the background. But ready-mix concrete does have one remarkable characteristic: other than manufactured ice, perhaps no other manufacturing industry faces greater transport barriers. The transportation problem arises because ready-mix concrete both has a low value-to-weight ratio and is highly perishable—it absolutely must be discharged from the truck before it hardens. These transportation barriers mean ready-mixed concrete must be produced near its customers. For the same reason, foreign trade in ready-mixed concrete is essentially nonexistent. This article is an introduction to the basics of the market for ready-mix concrete, focusing mainly on its consumers and its producers in the United States, but with occasional comparisons to other countries when contrasts are useful.