作为住宅大楼、桥梁、隧道等主要结构的混凝土也会受气侯、气象和地基变动等因素的影响而引起变化。因此,定期予以检查是必要的。本文是在建筑现场采用无损检测的方法进行实际测量的几个例子。对于由碎石、砂子、水泥加水搅拌而成的混凝土,利用X线和超声波检测被认为是最好的方法。一般认为X线属于电磁波,超声波则属于弹性波。但由于混 As a residential building, bridges, tunnels and other major structures of concrete will be climate and climate changes and other factors caused by changes. Therefore, regular inspection is necessary. This article is a few examples of actual measurements using NDT methods at the construction site. For concrete made from gravel, sand and cement mixed with water, X-ray and ultrasonic testing are considered the best methods. Generally believed that the X-ray belongs to the electromagnetic wave, the ultrasonic wave belongs to the elastic wave. But due to mixed