抗拔试验是专门为进行混凝土现场检验而设计的一种方法,它能直接测定指定部位的混凝土强度,与采用标准方法测得的28天强度具有较好的相关性。现有的一些抗技试验的缺点是必须在混凝土浇注过程中布置和埋设抗拔螺杆。本文介绍的两种新的抗拔试验方法,不但克服了现有方法的缺点,而且具有设备轻便,技术要求不高,操作简单等优点。一、试验设备和作用原理 1.方法Ⅰ试验装置主要由抗拔螺杆、连接小型油泵的千斤顶和底座组成,见图1、2。试验前先用专门设备在硬化的混凝土上钻出垂直于混凝土表面的孔洞,孔洞直径为19毫米,深38毫米。孔洞清洗干燥后, The pull-out test is a method specially designed for the concrete site inspection. It can directly measure the concrete strength of a specified site and has a good correlation with the 28-day strength measured by the standard method. The disadvantage of some existing resistance tests is that the pull-out screw must be arranged and embedded in the concrete pouring process. The two new pullout test methods described in this paper not only overcome the shortcomings of the existing methods, but also have the advantages of light weight, low technical requirements, and simple operation. First, the test equipment and the principle of action 1. Method I test device is mainly composed of pull-out screw, jack and base connecting small oil pump, see Figure 1, 2. Before the test, special equipment was used to drill holes perpendicular to the concrete surface in the hardened concrete. The holes had a diameter of 19 mm and a depth of 38 mm. Holes are cleaned and dried