中文摘要：

结合长春龙家堡机场航站楼大跨度预应力梁锁孔检测的工程实例，介绍用超声脉冲波法检测预应力混凝土梁预留孔道的灌密情况．讨论提高超声波检测混凝土构件的准确度问题．并在现有检测规程的基础上将超声检测技术的方法进行了改进，为有效监测预应力混凝土梁的施工质量提供科学可靠的保障．

英文摘要：

Taking the detection of large-span prestressed beam＇ s ducts of station building at Changchun Longjiapu Airport for instance, how to detect the grouting density of the prestressed beam＇s pipeline with ultrasonic method is described; and how to improve the veracity with ultrasonic detecting concrete component is dis- cussed too. The results can improve the ultrasonic method on the basis of existed technical specification and offer a reliable guarantee for the construction quality of prestressed concrete beams.