筒易人工反循环钻探方法

在水文地质条件极其复杂的淡水区,淡水底板的深度、含水砂层的厚度和位置及其下有无可利用之微咸水等,在平面上和垂向分布上往往变化甚大.虽只有几十米之距,条件却相差甚远。因此要保证有把握地掌握成井条件,仅靠大范围的勘探资料是难以奏效的。我们在“景县杜桥井灌试区”的建设中,研究并试制了一种简易人工反循环勘探方法.

Analysis on the mechanism and characteristics of concrete strength testing methods

This paper mainly described five kinds of common detection methods, including the test block method, core drilling method, rebound method, dialing out method and ultrasonic testing method and systematically analyzed the mechanism of all kinds of concrete strength detection methods as well as their advantages and disadvantages, which would provide a guide for construction personnel and research institutions to choose an economical ,accurate and safe detection method.