有两根条件相同的受弯构件,正截面受拉区受拉钢筋的配筋率一根大,另一根小,Mcr是正截面开裂弯矩,Mu是正截面极限抗弯弯矩,则( )。
A campus emergency ______ occur at any time of the day or night, weekend, or holiday, with little or no warning.
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