burst at the seams

中国では大気汚染の影響で人々の交通手段に影響が出ています。以下，JT（2013/01/31付）Beijing’s smog ‘beyond index’ againから抜粋。
Beijing’s official readings for PM2.5 were lower than the embassy’s — 433 micrograms per cu. meter at one point in the afternoon— but even that level is considered “severe” and prompted the city government to advise residents to stay indoors as much as possible. The government said that because there was no wind, the smog probably would not dissipate quickly.
Visibility was less than 100 meters in some areas of eastern China, the official Xinhua news agency reported. More than 100 flights were canceled in the eastern city of Zhengzhou, 33 in Beijing, 20 in Qindao and 13 in Jinan.
Every year, China’s transport system bursts at the seams as tens of millions of people travel for the Lunar New Year holiday, in the world’s largest seasonal migration of people.
今回の表現はburst at the seamsです。直訳すると「縫い目のところではちきれそうになっている」となるが，さらに辞書を引くと「〈場所が〉（人・物で）あふれている」と記されている（『ジーニアス英和辞典』第4版，大修館書店）。毎年，中国では旧正月の時期になると人々の移動が激しさを極めます。今回の表現は，交通機関が超満員になる様子を表しています。直訳のイメージと結びつけて覚えておきたいです。（GP）