The ratio between major and minor principal stresses basically keeps stable, while it varies between filling and impoundment periods. 大主應(yīng)力與小主應(yīng)力之比基本保持恒定，但填筑期及蓄水期的比值大小不同。
After one year's impoundment of the reservoir, the eco-environment of the middle and lower Yangtze is briefly presented in this paper. 本文對三峽工程蓄水一年來有關(guān)長江中下游的生態(tài)環(huán)境進行介紹。