03:50More or LessThe Concrete Facts about Trump’s Wall and ChinaBBC World Service Duration: 9 minutes Mon 20th Mar 2017, 03:50 on BBC World Service OnlineAvailable for over a yearListen nowDid China use more concrete in three years than the US in the 20th Century? Show more GenresFactualFormatsMagazines & ReviewsBrandMore or Less Source: BBC Online