发布时间:2025-02-02 03:04:26
M配(试配强度)=1.15(系数)M28(设计强度);
Qc(水泥)=( M配/K(经验系数)*Rbc(水泥标号))*100%;经验系数取5;
M20=1.15*20=23MPa:
Qc(水泥)= (230KG/0.735*42.5)*100%=186kg;
砂子的密度=1500kg/cm^2
Qc/S=186/186:1500/186=1/8
186/1300=0.143m^3;
0.143/0.143:1/0.143=1:6.99;
一个星期前用t字芽接的桃树到现在没发芽嫁接时接芽有点嫩现在怎么判断是否成活如果是活
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