Taking the commercial concrete in Zhengzhou as example,nondestructive tests are carried out by coring drilling,back-install evulsion,springing,from which concrete intensity is reckoned.

• 以郑州市商品混凝土为例,对其中12个素商品混凝土构件,进行了钻芯法、后装拔出法、回弹法等非破损检测试验,根据试验数据,推定了混凝土强度。